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User Manual MAN001-C

Taugagreining hf

Armuli 10

108 Reykjavík, Iceland

Tel: +354 580 7500

Fax: +354 580 7501

www.nervus.is

[email protected]

The Nervus range of Multimedia EEG systems has been designed and manufactured by Taugagreining hf, an Icelandic company that has always had an enviable reputation for innovation and quality of its products. Taugagreining hf has been certified by SEMKO as an

approved medical devices manufacturer as meeting the requirements of the Medical Devices Directive (93/42/EEC)

Taugagreining hf quality management system has been certified by SEMKO-DEKRA to comply with ISO 9001:2000.

The Nervus range of EEG systems has been independently tested and successfully approved to the following medical safety standards: EN 60601-1, EN 60601-1-2, IEC 601-1, IEC 601-1-2, UL 2601-1, CAN/CSA-C22.2 No. 601.1-M90, JIS T 1001/JIS T 1002 or JIS T 0601-1.

0413 The Nervus range of EEG systems is CE Marked in accordance with the European Council Directive 93/42/EEC concerning medical devices.

Caution: in the USA federal law restricts this device to sale by, or on the order of, a physician

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Copyright All rights reserved. This manual contains proprietary information which is protected by copyright and may not be copied in whole or in part except with the prior written permission of Taugagreining hf. The copyright and the foregoing restrictions on the copyright use extend to all media in which this information may be preserved.

This copy of the User Manual shall be used only in accordance with the conditions of sale of Taugagreining hf or its distributors.

Taugagreining hf makes no representations or warranties of any kind whatsoever with respect to this document. Taugagreining hf disclaims all liabilities for loss or damage arising out of the possession, sale or use of this document.

Nervus® is a registered trademark of Taugagreining hf.

Medelec® is a registered trademark of Oxford Instruments Medical.

TECA® is a registered trademark of Oxford Instruments Medical.

Microsoft® Windows®, Windows NT®, Windows XP® and Office® are registered trademarks of Microsoft Corporation.

Intel Pentium® is a registered trademark of INTEL Corporation.

All other trademarks and product names are the property of their relevant owners.

Taugagreining hf Ármúli 10 108 Reykjavik Iceland Tel: +354 580 7500 Fax: +354 580 7501 www.nervus.is

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Contents

1 General Introduction 1 1.1 This Manual 1 1.2 Disclaimers and warranties 2 1.3 General handling precautions 4 1.4 Installation 8 1.5 The Nervus EEG system 12 1.6 Product variants 16 1.7 Maintenance 22 1.8 Electrical interference suppression 24

2 System connections 27 2.1 Connecting the equipment 27 2.2 Switching on and switching off 37 2.3 Connections diagrams 39

3 Quick Tour of Nervus 53 3.1 Nervus Study Room 53 3.2 The Nervus Recorder 55 3.3 The Nervus Reader 58 3.4 Pruning 60

4 Nervus Study Room 63 4.1 Overview of workspace 63 4.2 Menus and Toolbar commands 68 4.3 Networking 93 4.4 Windows Explorer 93

5 The Nervus Recorder 95 5.1 Overview 95 5.2 Recorder interface components 95 5.3 Acquisition 111 5.4 Protocol 115 5.5 Events 116 5.6 Remote Control 119 5.7 Keystroke shortcuts 120

6 The Nervus Reader 122 6.1 Introduction 122 6.2 Nervus Reader interface components 123 6.3 Navigating through a recording 124

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6.4 View Menu 128 6.5 Protocol 147 6.6 Tools Menu 147 6.7 Workspace Menu 148 6.8 Window Menu 150 6.9 Remote Live Review 152 6.10 Keystroke Shortcuts 153

7 Settings 156 7.1 Customizing Nervus 156 7.2 Recording Protocol 156 7.3 Settings Editor 158 7.4 Options 183

8 Archiving 184 8.1 Setting up the Archive paths 184 8.2 Archiving to DVD 185 8.3 Archiving to CD R/W 188 8.4 Retrieving archived records 189

9 Web Reader 190 9.1 Test List 190 9.2 Searching for Tests or Patients 191 9.3 Test Properties 192 9.4 EEG Review 193

10 Specifications 197 10.1 M40 amplifier 197 10.2 M24 amplifier 199 10.3 C32 amplifier 201 10.4 C64 amplifier 203 10.5 U32 amplifier 205 10.6 Photic stimulator 207 10.7 ISO1000 isolation transformer 207 10.8 Medical power supply for Notebook, U32, IBox 207

1 General Introduction

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1.1 This Manual

Intended readers The Nervus Multimedia EEG System facilitates the capture and review of electroneurophysiological data. We have written this manual for those experienced in this field – administrative staff, nurses, technicians and physicians who will be using this application. As the Nervus System is designed for the Microsoft® Windows® operating system, you will need to be familiar with its basic features. Refer to the documentation supplied with Microsoft® Windows®.

Basic organisation This manual covers all aspects of using the Nervus EEG System for day-to-day operations. The first chapter provides an overview of the equipment required for operating the Nervus system, general handling and safety precautions, and an outline of the system’s key features.

The remaining chapters, which form the bulk of the manual, are reference materials on using the Nervus software and administration of a Nervus site. These chapters are designed to enable you to start using the application’s main features immediately.

Other manuals For more information, see also: Nervus Service Manual Nervus System Administrator’s Guide

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1.2 Disclaimers and warranties

The information in this section is subject to change without notice.

Except as stated below, Taugagreining hf (TG) makes no warranty of any kind with regard to this equipment, including, but not limited to, the implied warranties of merchantability and fitness for a particular purpose. TG shall not be liable for errors contained herein or for incidental or consequential damages in connection with the furnishing, performance or use of this equipment.

TG shall warrant its products against all defects in material and work-manship for one year from the date of delivery.

Misuse, accident, modification (including but not limited to the fitting to the PC of cards and disk drives not approved by TG and the loading of any software not approved by TG), unsuitable physical or operating environment, improper maintenance or damage caused by a product for which TG is not responsible will void the warranty.

TG does not warrant uninterrupted or error-free operation of its products.

TG or its authorised agents will repair or replace any products which prove to be defective during the warranty period, provided that these products are used as prescribed in the operating instructions in the user’s and service manuals.

No other party is authorised to make any warranty to assume liability for TG’s products. TG will not recognise any other warranty, either implied or in writing. In addition, services performed by someone other than TG or its authorised agents or any technical modification or changes of products without TG’s prior written consent may be cause for invalidating this warranty.


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Defective products or parts must be returned to TG or its authorised agents, along with an explanation of the failure. Shipping costs must be prepaid.

TG manufactures hardware and software to be used on or with standard PC-compatible computers and operating software. TG, however, assumes no responsibility for the use or reliability of its software or hardware with equipment that is not furnished by third-party manufacturers accepted by TG at the date of purchase.

All warranties for third-party products used within the Nervus EEG System are the responsibility of the relevant manufacturer. Please refer to the relevant documentation on each product for further details.

This document contains proprietary information that is protected by copyright. All rights are reserved. No part of this document may be photocopied, reproduced in any other form or translated into another language without the prior written consent of TG.

© Taugagreining hf 2003

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1.3 General handling precautions

Staff qualifications and system components The Nervus EEG system is intended for use only by qualified medical personnel, doctors, specialists and technicians.

The Nervus system is a combination of software and hardware modules manufactured by Taugagreining hf, and standard PC computer equipment manufactured by third parties. The following specification and safety standards apply to the system as a whole and individual components manufactured by Taugagreining hf. For detailed descriptions of third-party products, please refer to the relevant documentation from manufacturers.

The system is based on a standard PC (tower or notebook) running the Windows XP operating system. For faster processing and added ease, standard PC equipment can be added, such as a printer, video cards etc. Only PC cards and drives approved by Taugagreining hf may be fitted into the PC. (Applies to Notebooks too).

Each part of the software, such as the Nervus Recorder for acquisition and the Nervus Reader for reviewing, can be purchased individually for each station.

For on-line storage, a hard disk can be added. Archiving requires standard long-term storage media such as DVD+WR, optical drives, etc.

Important: any hardware connected to the system MUST be approved by Taugagreining hf to ensure that it meets the medical safety standards.

A recording station is equipped with a Nervus amplifier unit and audio/video capture kit.


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An ambulatory tape recorder, such as the Medelec MR95 recorder, can be used to record ambulatory EEG signals which can be imported to the Nervus EEG system via the Nervus HTP unit.

For networking, we recommend a dedicated Nervus PC running Windows XP. The system can be adapted to most kinds of LAN, high-speed networks, ISDN, etc.

Safety standards The system is designed to comply with the following medical safety standards: IEC601-1 International standard for medical electrical

equipment, general requirements for safety. EN60601-1 European standard for medical electrical

equipment, general requirements for safety. UL2601-1 USA standard for medical electrical equipment,

general requirements for safety. CAN/CSA 22.2 NO.601.1

Canadian standard for medical electrical equipment, general requirements for safety.

EN60601-1-1 European standard for medical electrical equipment, collateral standard safety requirement for medical electrical systems.

EN60601-1-2 European standard for medical electrical equipment, collateral standard - Electromagnetic compatibility.

EN60601-2-26 European standard for medical electrical equipment – particular requirements for the safety of electroencephalographs.

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Type of protection against electrical shock Class 1

Degree of protection against electrical shock Type BF

Degree of protection against harmful ingress of water

Ordinary (no protection)

Mode of operation Continuous

Degree of safety of application in the presence of a flammable anaesthetic mixture with air or with oxygen or nitrous oxide

Not suitable

Cautions and warnings It is the responsibility of the user to ensure that conformance to EN 60601-1 Type BF patient isolation requirements is maintained when patient-connected equipment or accessories not supplied by Taugagreining hf or its authorised agent are used with Taugagreining hf equipment.

Full compliance of Nervus systems cannot be ensured unless all com-ponents (leads etc.) are provided by Taugagreining hf or it authorised agent.

Any non-medical equipment connected to medical equipment to form a medical electrical system must comply with an appropriate safety standard, for example IEC60950, EN60950, UL1950, CAN/CSA22.2 No 950.

Items not specified as part of a Nervus system must not be connected to a Nervus system.

The operator must not touch any parts of non-medical electrical equipment (monitor, PC, printer, etc) supplied as part of the Nervus system that may be exposed after removal of covers, connectors, etc which do not require the use of a tool and the patient simultaneously. For example, do not touch the pins of the serial port connector on the PC and the patient simultaneously.

The brakes fitted to the trolley castors should be applied whenever the system is left unattended.


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Leakage current This instrument is designed to comply with the European standard for medical electronic equipment EN60601-1, which lays down the permiss-ible levels of leakage current from individual products. A potential hazard exists in the summation of leakage currents caused by connecting multiple pieces of equipment together. Because this instrument can be used in conjunction with standard electronic devices, the total leakage current should be tested at regular intervals.

Responsibility of manufacturer The manufacturer and distributor consider themselves responsible for the equipment’s safety, reliability and performance only if: l the Nervus system is run on standard PC equipment from third-party

providers recommended by the manufacturer. l assembly operations, extensions, readjustments, modifications, or

repairs are carried out by persons authorised by the manufacturer; l the electrical installation of the relevant room complies with the

appropriate requirements; l the equipment is used in accordance with the instructions for use.

Note: the manufacturer has a policy of continual product improvement; hence the equipment specifications are subject to change without notice.

Disposal of equipment When the equipment comes to the end of its operating life, it should be disposed of in accordance with local waste disposal regulations. Advice on this can usually be obtained from the local waste regulation authority which is typically found within the local government office.

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1.4 Installation

Warnings The following section must be read and understood before the equip-ment is switched ON.

The function or safety of the equipment could be impaired if it has been subjected to unfavorable conditions in storage or in transit. If, at any time, function or safety is thought to be impaired, the instrument should be taken out of operation and secured against unintended use.

Advice to the installer To enable the user to achieve optimal use, the installer should ensure that: l all cables are routed neatly and secured using the cable management

facilities provided; l the system is connected to a suitable wall socket outlet with a proven

protective earth connection; l on systems using the single pole trolley, the heights of the

keyboard/notebook shelf, the LCD monitor (tower PC systems) and the amplifier and photic stimulator arm mounting blocks allow the user to operate the equipment comfortably;

l the system is handed over to the user in such a condition that the user may simply switch it on and then use it for its intended purpose.


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Checks for completeness and integrity Remove the equipment from the packaging case(s) and use the parts list to check that all ordered items have been received.

Assembly instructions for third-party products may be found in their packing cases. It is recommended that these instructions be filed with Nervus technical reference materials.

Check for signs of damage which may have occurred during transit or storage. If any damage is found, do not use the instrument; contact your distributor.

Environmental parameters for operation The equipment is designed to operate within the following ranges: Temperature +5°C to +35°C (+41°F to +95°F) Relative humidity 20% to 80% RH (non-condensing) Atmospheric pressure range 700-1060 hPa During transport and storage, the following ranges are tolerated: Temperature –20°C to +65°C (–4°F to 149°F) Relative humidity 10% to 85% RH (non-condensing) Atmospheric pressure range 500-1060 hPa l Do not obstruct the cooling slots. l Position the equipment so that air flows freely from the

cooling slots. l Do not use the equipment in the presence of flammable,

anaesthetic gases. l All parts of the Nervus systems supplied by Taugagreining hf

may be placed within the patient environment.

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Power supply connections Nervus systems are suitable for connection to a single phase public mains supply network. The wall socket outlet(s) to which a Nervus system is connected must provide a protective earth connection.

Power requirements for the complete system For systems with ISO1000 transformer: 100-120V/200-240V~ (user adjustable in mains inlet module); 1050VA for 110-120V/200-240V~ input (950VA for 100V~ input); 50/60Hz

For notebook systems: 100V–240V; 70VA; 50/60Hz for medical power supply 115V/230V; 50VA; 50/60Hz for photic stimulator

For the power requirements of the notebook PC and printer, refer to the user manuals supplied by the manufacturers.

Mains power connections Instruments supplied in the USA and Canada have a power cord, connector and a hospital-grade AC mains power plug. Note that in the USA grounding reliability can only be achieved when the equipment is connected to an equivalent receptacle marked Hospital Only or Hospital Grade.

Instruments supplied to other countries have a power cord and connector, but may not have a mains power plug.

The wires of the mains power cable are color-coded:

color connection brown live blue neutral green/yellow protective earth


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When a mains plug is fitted, ensure that the correct connections are made.

The protective earth wire (green/yellow) must be connected to the protective earth conductor.

For instruments supplied in the UK, the USA and Canada, the protective earth connection is automatic when an appropriate and correctly wired socket is used.

When the mains plug is designed to hold a fuse, a 7A rated fuse should be used for the lead supplying the ISO1000; a 3A fuse should be used for the ‘Y’ lead supplying the medical power supply PSU001 and the power supply for the notebook PC.

The power cord and connector supplied with the instrument or a lead and connector of equivalent standard should be used with the instrument. Do not use adapter plugs or extension leads.

Only appropriately trained and qualified personnel should adjust, maintain or repair an instrument when it is connected to the mains electricity supply. If the cover must be removed, the instrument should be disconnected from the mains electricity supply.

Note: please refer to appropriate technical manuals for detailed information on third-party products.

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1.5 The Nervus EEG system

The Nervus Multimedia EEG system records and processes EEG and polygraphy signals using a standard PC running Windows XP. The following section covers key features of the Nervus system and the soft-ware components.

Key features l Use of the Windows XP operating system to record and process

digital EEG data; l Seamless integration with standard software such as Microsoft Office. l Acquisition of up to 128 EEG channels and other biological signals

and storage to a file; l Simultaneous acquisition and display of data, including digital video; l Insertion of user-defined and automatically inserted event markers

during recording, and the ability to browse the recording by events; l Custom montages (with complete control of paper speed, sensitivity,

signal derivation and filter settings); l Review of previous parts of the recording while still recording; l Page-by-page browsing through a recording or continuous playback

(forward or backward); l Trend Overview and the ability to browse the recording by selecting

a point on the overview; l Recording Protocol: a group of format and view settings, with instant

return to saved configurations; l Photic stimulation control from the recorder. The user can create

their own Photic sequences and execute them from the recorder. Duration events specifying the frequency are inserted while flashing;

l Hyperventilation and Reaction Time tools; l Continuous Impedance Testing while recording with automatic event

insertion when a poor electrode connection is detected; l Low cut, high cut and notch filtering; l Calculation of Fourier transformation.

Optional features l Acquisition of digital video to a file and synchronization to the EEG;


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l Alerts – Notification by email or a custom launched program when specified events occur.

Software The Nervus software co-ordinates all the hardware functions, translates the data into a comprehensible form, performs some automatic analysis and provides an interface enabling you to operate the system. Nervus consists of a number of software modules: Nervus Study Room Nervus’s starting point, this program provides access to all other parts of the system, such as recording, reviewing or archiving an EEG recording, opening a patient folder or editing a patient entry in the Nervus database. Nervus Recorder This program is used for the acquisition of EEG. The program allows you to acquire, mark and record comments on electro-physiological data and to record synchronous digital video. Nervus Reader This application enables you to review and analyse EEG files, supporting derivation, filtering, and topographical maps.

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Nervus accessories A wide variety of accessories is available for Nervus systems including electrode kits. Please contact your local distributor for details. Nervus concepts and terminology Nervus is a multimedia EEG system based on standard, IBM-compatible PC computer equipment. The Nervus software operates within the Microsoft Windows environment; thus users who are familiar with Windows will feel at home when working with Nervus. Floating toolbars, menus, mouse clicks etc., follow standard Windows guidelines, and in this manual we assume that you are familiar with these devices and operations. If not, please refer to your Windows documentation for more information.

Multimedia EEG The Nervus Multimedia EEG system uses synchronous digital video with the corresponding physiological information.

Storing EEG data in a digital format has many advantages over the conventional methods. Data can be reviewed and reformatted, thus enhancing the clinical utility of each recording. Tests can easily be accessed and reformatted by anyone connected to the central database. Reports can include visual information obtained directly from the source, including EEG traces, topographical maps and video recordings of the patient. Even live links can be inserted giving direct access to data for further analyses.


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Standard Interface Because of the standard Windows interface to the system, you are always on familiar ground, regardless of the application you are using. You do not have to learn multiple commands and functions. Also, this arrangement offers a unique way of interfacing the EEG tests and data with standard reporting applications such as MS Word for Windows.

Anti-virus software There are a number of file types associated with the Nervus system that must be excluded when scanning disks with anti virus software. The method for specifying file types for exclusion varies according to the anti virus software package you are using. Please refer to the documentation accompanying the anti virus software for instructions on how to do this.

The following file types must be excluded: *.e *.avi *.eeg *.edf *.bsa *.95

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1.6 Product variants

The Nervus Multimedia EEG system is available in a variety of product variants. l 40 Channel Desktop l 24 Channel Desktop l 32/64/128 Channel LTM Desktop l 32 Channel USB Notebook l 40 Channel Notebook l 24 Channel Notebook The Nervus 40 Channel Desktop uses a tower PC and the M40 amplifier which handles up to 40 EEG and polygraphy channels. It requires the installation of the USBIFB/01 interface card in the tower PC. The M40 amplifier supports electrode impedance checking.

The Nervus 24 Channel Desktop uses a tower PC and the M24 amplifier which handles up to 24 EEG and polygraphy channels. It requires the installation of the USBIFB/01 interface card in the tower PC. The M24 amplifier supports electrode impedance checking.

The Nervus 32/64/128 Channel LTM Desktop uses a tower PC and the C32 or C64 compact amplifier which handles 64 channels, or 2 amplifiers can be connected to handle 128 channels. This system requires the USBIFB/01 interface card to be installed in the tower PC.

The Nervus 32 Channel USB Notebook uses a notebook PC and the U32 USB amplifier which handles up to 32 channels and connects directly to the USB port of the computer.

The Nervus 40 Channel Notebook uses a notebook PC and the M40 amplifier. This system requires the Ibox interface box to connect the amplifier to the notebook PC. The Nervus 24 Channel Notebook uses a notebook PC and the M24 amplifier. This system requires the Ibox interface box to connect the amplifier to the notebook PC.

All Nervus amplifiers are fitted with a green LED to indicate when power is applied to them.


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The table on the following pages shows the standard and optional components of each variant.

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Nervus System Configurations X = Standard O = Optional

40 c

han

nel

Des

kto

p

24 c

han

nel

Des

kto

p

32/6

4/12

8 ch

ann

el L

TM

Des

kto

p

32 c

han

nel

USB

No

teb

oo

k

40 c

han

nel

No

teb

oo

k

24 c

han

nn

el N

ote

bo

ok

Hardware

Desktop PC X X X - - -

Notebook PC - - - X X X

Monitor X X X - - -

M40 Amplifier X - - - X -

C32 Amplifier - - O - - -

C64 Amplifier - - O - - -

U32 Amplifier - - - X - -

M24 Amplifier - X - - - X

IBox - - - - X X

Nervus Photic O O O O O O

ISO1000 X X X - - -

ISB060W - - - O i O i O i

Medical Power Supply PSU001

- - - X X X

i Required if printer or other externally powered peripherals are to be connected to the system


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Accessories

Single Pole O O O O O O

Knurr Trolley O O O - - -

Minicart - - - O O O

Carry Case - - - X X X

Software

Study Room X O X X X O

Recorder X X X X X X

Reader X X X X X X

Video O O O O O O

Spike & Seizure O O X O O O

Trend Analysis O O X O O O

Selective Video O O X O O O

Alerts O O X O O O

Maps O O O O O O

A range of accessories is available. Please contact the manufacturer or your local distributor for details.

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Transporting the system Follow the procedures for switching OFF (see above) before transporting the system.

Note: it is important to remove all disks from floppy and optical drives. If this is not done, the drives may be damaged.

Special instructions for use

General Switch ON the instrument (see chapter 2) before connecting patient electrodes.

Disconnect all patient electrodes before switching OFF (see chapter 2).

Conductive parts of the electrodes, including the neutral electrode, should not come into contact with other conductive parts including earth.

Switch OFF the mains electricity supply and pull out the mains electricity supply plug before disconnecting any items of equipment. Defibrillators

IMPORTANT: Before a defibrillator is used on the patient, disconnect the amplifier from the Nervus system as described below:

U32 systems Disconnect the USB cable, the dc power cable and the photic stimulator cable from the U32 amplifier.

M40 systems Disconnect the amplifier/photic cable from the M40 amplifier.

M24 systems Disconnect the amplifier/photic cable from the M24 amplifier.

C32, C64 Disconnect the quick release connectors joining the compact amplifier cable to the compact amplifier single or double cable.


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Using electrosurgical systems: risk of burns During electrosurgical procedures, high levels of radio frequency power are used and burns may occur at sites other than those intended, in particular at the sites of monitoring electrodes.

If you intend to use electrosurgical equipment at the same time as the Nervus, please take the following precautions:

l Use isolated-type diathermy equipment which meets the requirements of EN60601-2-2.

l Use diathermy equipment which continuously monitors the impedance of the connection to the dispersive electrode and warns when the impedance becomes unacceptably high

l Follow the manufacturer’s instructions for the attachment of the dispersive electrode:

Do not permit the active diathermy electrode to become grounded when it is energised. This can cause severe burns at the site of monitoring electrodes due to electrical current flowing from the dispersive electrode to ground via the active diathermy electrode.

Use electrodes with large monitoring areas where possible. Do not use electrodes with small monitoring areas, for example needle electrodes. These electrodes concentrate the radio frequency energy more than large area recording electrodes and make the recording sites more susceptible to burns.

When small area electrodes have to be used, add a 10kΩ resistor in series with each recording electrode to reduce the risk of burns. Do not put a resistor in series with the neutral electrode because this will degrade the quality of the recording - use a large area neutral electrode.

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1.7 Maintenance

Warning: there are no user-serviceable parts inside the instru-ment. Only appropriately trained and qualified personnel should adjust, maintain or repair the instrument when it is connected to the electricity supply. The instrument must be disconnected from the electricity supply first, before any cover is removed.

The Nervus EEG System contains many solid-state electronic components which need no maintenance and no parts requiring periodic replacement. Furthermore, most hardware components of the Nervus system are standard PC equipment. They should be maintained according to the relevant manufacturer’s directions.

The notebook PC must only be powered by the model of power supply originally supplied with the system by Taugagreining hf. Note that the use of other models of power supply from the manufacturer of the PC or from other manufacturers, whilst they may power the PC correctly, may not comply with the leakage current requirements defined in the medical electrical systems standard EN60601-1-1.

Therefore in the event of failure the power supply for the notebook PC must only be replaced by one of the same make and model.

After-sales service support The manufacturer and distributors of Nervus EEG systems provide comprehensive after-sales service and support. Service contracts are available. For details, please contact the manufacturer or the local distributor.

A service manual is available for purchase containing all the information necessary to enable appropriately qualified technical personnel to carry out repair and calibration of those parts of the equipment that are repairable.


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Fuses Before removing a fuse, switch off the instrument and pull out the mains plug. Use a screwdriver to ease out the twin fuseholder. The fuses are extracted with the fuse holder and are simply pulled out.

Nervus Photic F1/F2 2 x T500 mA L 250V ISO1000 Isolation Transformer F3/F4: 200-240V – T6.3A H 250V

100-120V – T10A H 250V

If fuses fail repeatedly, contact the manufacturer or the local distributor.

For information on any user-accessible fuses in the PC, monitor and printer, please refer to the relevant third-party manufacturer documentation.

Regular testing of equipment and accessories Checks may be made using the inbuilt calibration and impedance check functions to confirm that the equipment and its accessories are oper-ating correctly.

Cleaning The user is advised to carry out cleaning as specified below, as and when required: l All the outer surfaces of the individual pieces of equipment of the

Nervus system may be cleaned using a cloth moistened with water and detergent. Do not allow any liquid to enter the case of any instrument.

l Each item may also be cleaned using a low-pressure air-line, or a vacuum cleaner with an appropriate attachment.

l Do not use propanone (acetone) on any of the instruments. l No part of the system may be autoclaved or sterilised by any means. l For advice on methods and frequency of cleaning the PC, monitor

and printer consult the documentation supplied with them.

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1.8 Electrical interference suppression

These notes are intended as a guide to identifying and suppressing electrical interference that may affect apparatus involving the detection and analysis of signals of a few microvolts in the frequency range DC to 20kHz, such as for Electroencephalographs (EEG).

Classification of interference sources 1 50Hz/60Hz magnetic field from power transformers, induction motors, etc

The only practical protection from this type of interference is the avoidance of loops in the pick-up circuits of the EEG, since the magnitude of the interfering voltages is directly proportional to the area enclosed by any such loop.

2 Magnetic field from staff location systems using inductive loops

This type of interference is of an intermittent character and may be serious where the inductive loop runs alongside the wall of the examination room and where the transmitted frequencies fall within the pass band of the EEG (DC to 20kHz).

Most modern staff location systems now use frequencies above 20kHz and should therefore cause minimum interference unless the loop is very close to the EEG.


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3 50Hz/60Hz electrostatic field from unshielded conductors, lamps, etc.

This type of interference is possibly the simplest to locate and correct. Any conductor of supply frequency not covered by an earthed metal screen is a potential source of interference. Obvious sources are flexible cables to desk lamps and X-ray viewing boxes, unshielded flourescent tubes and filament lamps.

It is important that all encasing metalwork of electrical equipment be securely bonded electrically to the local circuit earth.

4 HF interference from short-wave diathermy, radio, television and sound broadcasting

This class of interference is the most difficult to track down to its source and by far the most difficult to eliminate.

Short-wave diathermy is easily the most frequent source of HF interference, particularly in or near a physical medicine department or operating theatre.

The interference may reach the EEG via a number of paths falling into two main categories: (1) Conducted and (2) Radiated.

Conducted HF interference is the type found on the mains supply. This kind of interference is eliminated by efficient mains filtering on equipment.

Radiated interference is emitted from poorly screened electrical equipment or other sources such as cell phones, radio transmitters and hospital paging systems. In severe cases, a screened enclosure is essential.

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Sources of artefact l Dirty electrodes l Broken electrode lead wire including ground electrode wire l Electrode lead wire movement l Poor ground electrode location l Incorrect electrode connection to apparatus l Ungrounded wheelchair or table l Ungrounded observers l Microphony l Audio feedback l Pick-up from CRT screen l Power cables near patient not unplugged at wall socket l Poor apparatus ground l Fluorescent lights l Electronic dimmers l Intermittent power line load l Excessive low or high power line voltage l Diathermy l Radio and TV l Multiple grounds in screened room l Cell Phones

2 System Connections

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2 System connections

2.1 Connecting the equipment

IMPORTANT: For connections to the mains supply do not use any additional multiple portable socket outlets, adapter plugs, or extension leads. In particular the use of a multiple portable socket outlets runs the risks of a) the summation of earth leakage currents which may result in the allowable limits for medical electrical equipment and systems being exceeded, and b) the protective earthing of the system relying on the single earth connection to the multiple portable socket outlet.

Connect all the individual items of equipment before switching ON.

Connect only peripheral equipment supplied or approved by the manufacturer of the Nervus system.

Connecting the mains (Desktop systems)

Checks before switching on the system l Check that the ISO1000 mains isolation transformer input voltage is

set to match output voltage for your local mains supply. l Check that the input voltages of the photic stimulator, the PC tower,

the monitor and the optional printer are all set to match the output voltage of the ISO1000. Refer to the rating labels and user manuals of these equipments to check if adjustment is necessary and for information on how to carry out any required adjustments.

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Notes and warnings Note that the photic stimulator may be powered either directly from a separate wall socket outlet (do not use a multiple portable socket outlet) or from an outlet on the ISO1000 Mains Isolating Transformer, whichever is more convenient.

The non-medical equipment supplied as part of the Nervus Desktop systems – the tower PC, the monitor and the printer - must only be powered from the outlets of the ISO1000 mains isolation transformer. If non-medical equipment supplied as part of the Nervus Desktop systems were to be connected directly to a wall socket outlet then there may be a risk of allowable leakage currents being exceeded.

Note that the outlets of the ISO1000 mains isolation transformer must only be used to power equipment approved by Taugagreining hf. No other equipment may be powered from these outlets as there may be a risk of exceeding the power rating of the ISO1000 mains isolation transformer.

The maximum permitted load for the ISO1000 mains isolation transformer is 1000VA for 110-120V/200-240V~ ( 900VA for 100V~ ).

Check that the ISO1000 mains isolation transformer is not placed on the floor. A position is provided for it on the bottom shelf of the trolley.

Connection Connect the mains supply to the mains input connector of the ISO1000 mains isolation transformer using the lead supplied. Then connect the PC tower, the monitor and the printer to the isolated mains outlets of the mains isolation transformer using the IEC plug to IEC socket leads supplied with the system.


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Connecting the mains (Notebook systems) Note: if you are using a printer with the notebook PC, then a mains isolation transformer is required. If you are using the notebook PC supplied by Taugagreining hf, and do not have a printer connected, then you do not need a mains isolation transformer.

Connect the medical power supply PSU001 and the power supply provided by the manufacturer of the notebook PC to the mains supply using the special ’Y’-mains cable supplied with the system.

The notebook PC must only be powered by the model of power supply originally supplied with the system by Taugagreining hf. Note that the use of other models of power supply from the manufacturer of the PC or from other manufacturers, whilst they may power the PC correctly, may not comply with the leakage current requirements defined in the medical electrical systems standard EN60601-1-1.

Note that the Photic Stimulator and the Taugagreining hf approved printer must be powered directly from separate wall socket outlets otherwise allowable leakage currents may be exceeded. Do not use a multiple portable socket outlet.

Note that the printer(s) recommended by Taugagreining hf have been selected to comply with the earth leakage current requirements of standard EN 60601-1-1, safety requirements for medical electrical systems. The use of a printer other than one recommended by Taugagreining hf may result in allowable leakage currents being exceeded.

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USBIFB/01 interface card (Desktop PC systems) Connect the 300mm USB A-B cable supplied between the USB port of the PC and the USB port of the interface card. Connect the splitter cable to the 15 pin high density D-type socket. A 26-pin high density D-type socket is available for optional analogue in.

Note: make sure you are connecting the USB cable to the USB port on the PC, and not to the Network connector.

Nervus IBox and Medical Power Supply PSU001 Connect the USB A-B cable supplied between the USB connector on the end panel of the IBox and one of the USB connectors on the notebook PC - note that a different type of connector is used at each end of the USB cable.

Connect the dc power cable supplied, fitted with miniature 4pin circular connectors, between the socket on the junction box attached to the medical power supply PSU001 and the dc input plug on the end panel of the Ibox. These connectors simply push together and lock with an audible click. To disconnect pull (do not twist) the connectors apart.

Warning: in order to maintain patient and user safety, the Nervus IBox must only be powered from the medical power supply PSU001 .


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M40 amplifier (40 channel systems)

Two cables are supplied to connect the M40 amplifier to the Nervus 40 channel desktop or notebook system - a splitter cable and an amplifier/photic cable. Both these cables are fitted with 15pin high density D-type plugs and sockets.

For the notebook system: connect the plug of the splitter cable to the 15pin socket on the end panel of the Ibox interface unit.

For the desktop system: connect the plug of the splitter cable to the 15pin socket on the USBIFB/01 interface card fitted in the tower PC.

For both systems the plug of the amplifier/photic cable is connected to either of the two sockets of the splitter cable. The socket of the amplifier/photic cable is connected to the plug on the end panel of the Nervus M40 amplifier. (The second socket of the splitter cable is used to connect the photic stimulator.)

Tighten the jackscrews on all connectors so fitted.

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C32 and C64 compact amplifier (32, 64 or 128 channel systems) Note: the 32 channel Nervus system uses one C32 amplifier; the 64 channel Nervus system uses one C64 amplifier; the 128 channel Nervus system uses two C64 amplifiers.

Three cables are required to connect the C32, C64 or C128 compact amplifier to a 32, 64 or 128 channel system - a splitter cable, a compact amplifier cable, and either a compact amplifier single cable for the 32 and 64 channel system or a compact amplifier double cable for the 128 channel system.

Connect the plug of the splitter cable to the 15pin socket on the USBIFB/01 interface card fitted in the tower PC.

Connect the 15pin high density D-type plug of the compact amplifier cable to either of the two sockets of the splitter cable. Connect the quick release connector at the other end of the compact amplifier cable to the mating connector on either the compact amplifier single cable for the 32 and 64 channel system or the compact amplifier double cable for the 128 channel system.

Connect the 36pin SCSI connector(s) on the compact amplifier single cable or the compact amplifier double cable to the mating connector(s) on the C32 or C64 amplifier(s).



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U32 amplifier (32 channel notebook system)

Connect the USB A-B cable supplied between the USB connector on the end panel of the U32 amplifier and one of the USB connectors on the notebook PC - note that a different type of connector is used at each end of the USB cable.

Connect the dc power cable supplied, fitted with miniature 4pin circular connectors, between the socket on the junction box attached to the medical power supply PSU001 and the dc input plug on the end panel of the Nervus 32 amplifier. These connectors simply push together and lock with an audible click. To disconnect pull (do not twist) the connectors apart.

WARNING: in order to maintain patient and user safety, the U32 amplifier must only be powered from the medical power supply PSU001 .

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M24 amplifier (24 channel systems)

Two cables are supplied to connect the M24 amplifier to the Nervus 24 channel desktop or notebook system - a splitter cable and an amplifier/photic cable. Both these cables are fitted with 15pin high density D-type plugs and sockets.

For the notebook system: connect the plug of the splitter cable to the 15pin socket on the end panel of the Ibox interface unit.

For the desktop system: connect the plug of the splitter cable to the 15pin socket on the USBIFB/01 interface card fitted in the tower PC.

For both systems the plug of the amplifier/photic cable is connected to either of the two sockets of the splitter cable. The socket of the amplifier/photic cable is connected to the plug on the end panel of the Nervus M24 amplifier. (The second socket of the splitter cable is used to connect the photic stimulator.)



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Photic stimulator

A second amplifier/photic cable is supplied for connection of the photic stimulator. For the desktop systems Connect the plug of the amplifier/photic cable to the second 15pin socket of the splitter cable connected to the USBIFB/01 interface card when the amplifier was connected.

Connect the socket of the amplifier/photic cable to the 15pin plug on the rear panel of the photic stimulator.


For the notebook system Connect the plug of the amplifier/photic cable to the 15pin socket on the end panel of the U32 amplifier for 32 channel notebook system or the IBox for 24 and 40 channel notebook system.

Connect the socket of the amplifier/photic cable to the 15pin plug on the rear panel of the photic stimulator.


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Other standard PC equipment Please refer to relevant technical guides for the PC, monitor and printer for the positions of the relevant signal connectors. Suitable signal cables are provided with the system for connecting these equipments. High quality screened cables must be used when connecting to the interface connectors of Nervus to ensure compliance with EMC regulations. Braid screened or double screened (braid plus foil) cables are the preferred types. The cable screen should make a 360° connection to the screening shells of the connectors on each end of the cable.

Note that only printers approved by Taugagreining hf may be used with Nervus EEG systems configured without a mains isolation transformer. This is to ensure that these systems comply with the leakage current requirements defined in the medical electrical systems standard EN60601-1-1.

Cables l Position the equipment so that cables are not stretched and cannot

be pulled at or tripped over. l Always disconnect cables by pulling the plug, not the cables. l Wires within a cable may be damaged if the cable is stretched or

improperly disconnected; this damage may cause a failure in the supply of power or acquisition of data.

l It is recommended that cables and connectors are frequently visually inspected for signs of wear (for example, cracks or breaks). If necessary, do not use the cable but have it removed for service.

Dongle (copy protection key) To run the software, the dongle must be plugged into a USB port of your computer.


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2.2 Switching on and switching off

Switching ON Notes: As a safety precaution, switch ON before connecting patient electrodes. Do not disconnect any item of equipment when mains electricity is connected. (This does not apply to equipment utilising the USB Universal Serial Bus).

1 Connect all the peripheral items of equipment before switching ON. Connect only peripheral equipment supplied or recommended by Taugagreining hf.

2 Identify the connector on each of the electrical leads on individual items of equipment and push them firmly into position on the rear panel of the PC.

3 Before switching ON the PC make sure no floppy disk is in the external disk drive.

4 Connect the mains electricity supply and switch ON at the mains power plug. The mains power ON/OFF switch on the PC is a rocker or push button switch on the front of the panel. The indicator light on the front of the panel is ON when the switch is ON.

5 Press the power on button to start the PC. The PC is now ON and starts loading the appropriate Windows operating system (Windows XP).

Passwords You must enter a user name and password before you can run Nervus software or access any data. If you do not know what your user name and password are, consult your System Administrator.

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Switching OFF IMPORTANT: disconnect all patient electrodes before switching OFF.

1 Remove any floppy disk from the external drive and any optical disks before switching OFF.

2 Shut down the system using the Windows shutdown procedure. 3 Switch OFF at the mains power plug.


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2.3 Connections diagrams

Combined key for all diagrams 1 Photic stimulator 2 Photic and M40 amplifier signal cable 3 Mains inlet 4 IEC socket to local mains connector (3 core 16AWG) 5 IEC plug to IEC socket cable – output of ISO 1000 to PC tower, monitor,

printer etc. 6 M40 amplifier 7 U32 amplifier 8 C32 or C64 compact amplifier 9 dc power to IBox or U32 amplifier 10 IBox interface 11 USB signal cable 12 Splitter cable for photic and amplifier signals 14 Medical power supply 16 Taugagreining hf approved notebook PC 17 Mouse 18 Keyboard 19 USB signal cable ~ USB interface card to PC USB port 20 Nervus software hardware licence key (USB Dongle) 21 USB interface card 22 Long cable for C32 / C64 compact amplifier 23 Short cable for C32 / C64 compact amplifier 24 Short cable with link cable for second C32 / C64 compact amplifier 25 Monitor signal cable 26 Taugagreining hf approved monitor 27 Taugagreining hf approved tower PC 28 Taugagreining hf approved printer 29 Signal cable to printer 30 Isolated mains outlets 31 Isolation transformer (ISO1000 or ISB060W) 32 Separate fixed mains socket outlets 33 Wall of room 35 M24 amplifier 36 Junction Box 37 DC Power to Junction box

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40 channel desktop

1 Photic stimulator 6 M40 amplifier 26 TG approved monitor

2 Photic / amplifier cables

12 Photic / amplifier splitter cable

27 TG approved tower PC

3 Mains inlet 19 USB signal cable 28 TG approved printer

4 IEC socket to local mains connector

20 USB Dongle 30 Isolated mains outlets

5 IEC plug to IEC socket cable

21 USB interface card

31 ISO 1000 isolation transformer


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24 channel desktop

2 Amplifier cables 20 USB Dongle 30 Isolated mains outlets

3 Mains inlet 21 USB interface card



26 TG approved monitor

35 M24 Amplifier

5 IEC plug to IEC socket cable

27 TG approved tower PC

19 USB signal cable 28 TG approved printer

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32/64/128 channel LTM desktop

1 Photic stimulator 12 Photic / amplifier splitter cable

24 Short cable with link for second C32 / C64


19 USB signal cable 26 TG approved monitor

3 Mains inlet 20 USB Dongle 27 TG approved PC 4 IEC socket to local

mains connector 21 USB interface

card 28 TG approved

printer 5 IEC plug to IEC

socket cable 22 Long cable for

C32 / C64 30 Isolated mains

outlets 8 C32 or C64

compact amplifier

23 Short cable for C32 / C64



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32 channel USB notebook

1 Photic stimulator 9 dc power to U32 35 DC power to Notebook PC


11 USB signal cable 36 Junction Box

3 Mains inlet 14 Medical power supply

37 DC power to Junction Box


16 Notebook PC

7 U32 amplifier 20 USB Dongle

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40 channel notebook

1 Photic stimulator 9 dc power to IBox 16 Notebook PC 2 Photic / amplifier

cables 10 IBox interface 20 USB Dongle

3 Mains inlet 11 USB signal cable 35 DC power to Notebook PC



36 Junction Box

6 M40 amplifier 14 Medical power supply



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24 channel notebook

1 Photic stimulator 9 dc power to IBox 16 Notebook PC 2 Photic / amplifier

cables 10 IBox interface 20 USB Dongle

3 Mains inlet 11 USB signal cable 35 DC power to Notebook PC



36 Junction Box

6 M24 amplifier 14 Medical power supply


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Adding a printer to notebook systems

1 Photic stimulator 5 IEC plug to IEC socket cable

30 Isolated mains outlets


14 Medical power supply

31 Isolation transformer

3 Mains inlet 28 TG approved printer



29 Signal cable to printer


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Symbols and their definitions

v Direct current (DC)

Z Alternating current (AC)

w Off (main power supply)

x On (main power supply)

N Mains Isolation Transformer

f Danger – high voltage

e Type BF patient applied part

A Refer to accompanying documents

O Caution: to reduce the risk of electric shock do not

remove cover. Refer servicing to qualified service personnel.

P Before connecting refer to user manual.

Q Danger: risk of explosion if used in the presence of

flammable anaesthetics.

S No user serviceable parts inside.

U Before connecting ensure that mains voltages and fuse

ratings are correct

Z The Nervus IBox must only be powered from the Nervus

power supply - PSU001.

i The Nervus 32 amplifier must only be powered from the Nervus power supply - PSU001.

K Do not use in the presence of flammable anaesthetics.

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Connection symbols

I Input

X Output

o Input/Output

) Event marker

SpO2 Nonin XPOD oximeter

( Headcap connector

R1 Input for a respiration transducer fitted with 3.5mm jack plug.

R2 Input for a second respiration transducer fitted with 3.5mm jack plug.

P Input for a pulse transducer fitted with 3.5mm jack plug.

w Universal serial bus

b Equipotential earth For explanation of other symbols on the PC refer to the user manual for the PC.

External pin connections High quality screened cables must be used when connecting to the interface connectors of Nervus to ensure compliance with EMC regulations. Braid screened or double screened (braid plus foil) cables are the preferred types. The cable screen should make a 360° connection to the screening shells of the connectors on each end of the cable.


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Patient E-Cap 25 way D type socket (location: M40, M24, U32 amplifiers)

Amplifier

Patient E-Cap 25 way D type socket

Pin No. Service Left-Right Configuration Right-Left Configuration 1 Fp1 Fp2 2 F3 F4 3 C3 C4 4 P3 P4 5 O1 O2 6 F7 F8 7 T3 T4 8 T5 T6 9 NEUTRAL NEUTRAL 10 Fz Fz 11 A1 A2 12 PG1 PG2 13 REF REF 14 Fp2 Fp1 15 F4 F3 16 C4 C3 17 P4 P3 18 O2 O1 19 F8 F7 20 T4 T3 21 T6 T5 22 Cz Cz 23 Pz Pz 24 A2 A1 25 PG2 PG1

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26-pin high density D-type connector pin-out (location: USBIFB/01 interface card, Ibox or U32 amplifier)

Pin Signal Name Signal Description 1 AI1 (IP) Analog I/P Channel 1, ± 2.5V fsd. 2 - HDR2/22 3 - HDR2/23 4 - HDR2/19 5 - HDR2/15 6 - HDR2/11 7 P3.3 (IP) HDR2/2 and buffered digital I/P (P3.3) 8 P3.1 (InvOP) HDR2/5 (Issue 1 & 2) Issue 2 only - open-collector

(pull-up to +5V), inverted version of P3.1 (can be used as Serial O/P). Must be pulled down to -12V for RS232 purposes.

9 - (Issue 1) U+5V- (Issue 2)

HDR2/1 (Issue 1 & 2) Issue 2 only - 8x930Ax +5V power. Note: in bus-powered mode, this is USB-power so current drawn is < 500mA total. Only ever apply external +5V power to this pin if the USBIFB/01 is in self-powered mode.

10 AI2 (IP) Analog I/P Channel 2, ± 2.5V fsd. 11 AI4 (IP) Analog I/P Channel 4, ± 2.5V fsd. 12 - HDR2/24 13 - HDR2/21 14 - HDR2/17 15 - HDR2/13 16 - HDR2/8&9. 0V. 17 - HDR2/7 18 P1.0 (OP) HDR2/3 and open-drain, buffered version of P1.0,

current-limited by series 100Ω resistor (Issue 1 & 2) Issue 2 only - 4K7Ω pull-up to D+5V

19 AI3 (IP) Analog I/P Channel 3, ± 2.5V fsd. 20 - HDR2/18 21 - HDR2/16 22 - HDR2/14 23 - HDR2/12 24 - HDR2/10 25 - HDR2/6 26 P3.0 (InvIP) HDR2/4 (Issue 1 & 2) Issue 2 only - buffered,

inverted version connected to P3.0 (can be used as Serial I/P).

Shell GND Ground


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9 pin mini D-type connector pin-out (location: C32, C64)

Pin Signal name Signal description 1 AI1 Analog I/P Channel 1, ± 2.5V fsd. 2 AI3 Analog I/P Channel 1, ± 2.5V fsd. 3 GND Ground 4 +5v - 5 Dout Ground 6 AI2 Analog I/P Channel 1, ± 2.5V fsd. 7 AI4 Analog I/P Channel 1, ± 2.5V fsd. 8 GND Ground 9 Event Event signal, pull to ground to activate

5 pin mini circular connector pin-out (one digital input per 16 channels) (location: C32, C64)

Pin Signal name Signal description 1 D1 Digital input 2 D2 Digital input 3 D3 Digital input 4 D4 Digital input 5 GND Ground

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3 Quick Tour of Nervus

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This Quick Tour outlines a typical workflow for handling EEG recordings and provides sufficient information to get the user started. It does not cover all the features available. Further and more detailed information can be found in the following chapters on the Study Room, Recorder and Reader.

3.1 Nervus Study Room

The Nervus Study Room is designed to be your starting point for recording, reading and archiving EEG files. With its workflow-designed tabs, it assists you with administrative details involving patient registration, while also providing ready access to the Nervus Recorder and the Nervus Reader.

Patient registration The Nervus Study Room makes patient registration quick and sure. Its functions help you find existing patients’ records, register new patients quickly and automatically and see to it that patients are linked with their EEG recordings and other pertinent documents in the Nervus database.

Searching for an existing patient

Click the New Test button at the top of the Nervus Study Room workspace to open the New Test Wizard:

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In the New Test Wizard, select the Existing Patient radio button (this option is selected by default). To search for a patient, type the first few letters of the patient’s last name. The string “Jon” would return tests for patients whose last names begin with that string: Jones, Jonsson, Jonas, etc. You can narrow the search by typing more characters. Click on the Search button to start the search. Click the patient entry in the list, then Next, to move to the Test Info page.

Or, if the name appears on the list in the Study Room, simply double-click the name to skip the search step.

Registering a new patient When you select the New Patient radio button in the New Test Wizard and click Next, Nervus opens the Enter New Patient dialog.

Fill out this information and click Next to open the Test Info dialog. Fill out the information in the Test Info dialog and click Finish. This will place the test on the first tab (the Record Tab) in the Nervus Study Room. Patient information can be filled in after the EEG recording has been completed but the Test ID field must be completed.


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3.2 The Nervus Recorder

After the electrodes have been attached to the patient, select a test from the list on the Record Tab in the Nervus Study Room. Click the Record command

button on the right hand side of the Study Room to open the test in the Nervus Recorder.

Impedance test

Open the Impedance Test dialog by clicking the Impedance Test Toolbar button or choosing this command from the Acquisition Menu.

This dialog displays the result of the impedance check with color codes as well as a numerical value (measured in K-Ohms) for all the channels. The impedance of each channel is measured and compared against the threshold value as selected in the K-Ohm selection list. With color-coding, the impedance check can be performed at one glance.

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The colors have the following meanings: Green Impedance is lower than the value selected. Red Impedance is higher than the value selected. Grey Channel is not selected in the present amplifier setup.

Note: the highest number that can be displayed for a channel is 65.5 K-Ohms. If this number is present, it means that the value is 65.5 or higher.

Start recording

From the Acquisition Menu choose Record, or click the Record button on the Toolbar. The EEG traces will be visible in the Live EEG Pane of the Nervus Recorder as they are recorded.

Recording parameters

Changes to time-base and sensitivity can be made at any point during a recording session from the drop down lists on the Format panel, or from the Format Menu.


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Event markers

Custom event markers can be inserted on the fly into the Live EEG pane, or can be manually inserted into the Review pane.

Event markers are inserted into the Live EEG pane by clicking once on the event marker on the live event palette. Duration events (such as seizure) are marked by clicking once on the marker at the beginning of the event and again at the end point.

To insert event markers into the Review pane, click once on the event marker on the review event palette and once at the insertion point on the trace display. To insert a duration event, click the event marker, then the beginning insertion point, then scroll to the end point and click again on the trace display.

Stop recording

Press the Record button to finish the recording. This will discontinue the recording to disk without interrupting the trace display.

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Close the test Close the test by clicking the close button in the upper right window of the Recorder. The EEG data will automatically be registered in the data-base.

The test can then be moved to the Review Tab of the Nervus Study Room by selecting the name from the list on the Record Tab and clicking the Move > button on the right-hand side of the work area.

Moves a test to the next tab in the Study Room

3.3 The Nervus Reader

This section briefly describes the main features of the Nervus Reader.

Open a recording

Click to open the Nervus Reader

Select a test from the list on the Review Tab of the Nervus Study Room. Click the Review button.

Browsing through a recording

Click to page automatically backward or forward through a recording.

The slider bar controls the automatic paging speed.

You can browse through a recording in several ways. Use the Page Up and Page Down keys to manually page through the recording, or click on the right or left side of the trace display with the arrow cursor.

Changing parameters The recording is displayed in the As Recorded format. This means that all montage and parameter changes made during the recording will be


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seen. This is similar to how a paper EEG recording would be reviewed. However as you browse through the recording, you can change any parameters you wish. To get back to the test as it was recorded, just click on the As Recorded button on the Toolbar or select As Recorded from the montage selector on the Format panel. (To display the Format panel, if it is not displayed, choose Format Menu > View > Panel > Show)

Parameters can be changed by selecting values from the list boxes on the Format panel, by using the sensitivity and paper speed buttons on the toolbar, or by selecting items on the Format Menu.

Parameter controls on the toolbar

Event markers Mark events by clicking once on the Event button on the Event palette, then clicking again on the trace display at the point you want the event marked. To insert a Duration event (such as seizure), select the event and click once on the trace display at the starting point. Then scroll until you reach the end point and click again on the trace display.

Use the event list on the Panel to display all events placed in the recording. Click on an event to display the associated EEG. Right-click over the event to delete it.

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Reporting

In the Study Room, click on View Report.

Patient and Test information will automatically be entered into the report which uses a Word template. This template can be edited if necessary.

There are no limitations to the length of the report. Examples of waveforms can be copied and pasted into the report by using the Copy command under the Edit Menu in the Nervus Reader. Move to the report and use the Paste command from the Edit Menu in Word.

3.4 Pruning

When you have viewed the original recording, it can be pruned to reduce the length of the recording for archiving. This is best done by using the Duration events to mark sections of interest. The original recording in its entirety can also be saved if necessary.

The pruning function can be used in the Nervus Reader or from the main Study Room screen. From the Reader 1 Create a Prune Template in the Prune Settings part of the Protocol

Settings dialog. Select the events you want to keep and how many seconds before and after should be kept. Save the Prune Template to the Protocol.

2 Press the Prune button. This toggle button shows the file as it looks pruned but changes have not been saved. The original look can be recalled by pushing the Prune button again.

3 Use Save/Save As to save the changes you have made.


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From the Study Room Select a test to prune and choose Test Menu > Prune to open the Prune Settings dialog. Complete step one above. When you click OK, you will be asked if you want to keep the original recording in addition to the pruned version.

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4 Nervus Study Room

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4 Nervus Study Room

4.1 Overview of workspace

The Nervus Study Room is your starting point and command center for the Nervus system, providing convenient workflow control for making, reviewing and archiving recordings. The following sections will introduce you to the principles and functions of the Nervus Study Room workspace.

Nervus Study Room interface Below is the Nervus Study Room you see just after you have started the program:

For key see following page.

1 2

3 4

5

6

7 8 9

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Key to Study Room diagram 1 Menus 2 Toolbar Buttons (hide or show via View Menu) 3 Fixed Command Buttons 4 Workflow Tabs 5 Column Headings (Click on any column heading to re-sort list using

the heading as a key, in this example, alphabetically by last names) 6 Tests in progress (in this example, on the Record List tab). 7 Status Bar (hide or show via View Menu) 8 User – the currently logged in user. 9 Patient ID of selected (highlighted) test. Workflow design with tabbed list boxes Workflow is designed into the Nervus Study Room with tabbed list boxes. The tabs – Record List, Review List and Archive List – follow the stages of a recording. You begin a new test on the Record List tab by creating a test record, linking it to a patient and recording the test. When the recording is finished, select it from the list on the Record List tab and click the Move > button to move the record to the Review List tab. When you have finished reviewing the recording, select it on the Review List tab and click Move > to move the test to the Archive List tab.

You can re-sort the lists on each tab using any column heading as the sort key by clicking on the column heading. You can reverse the sort order by clicking the relevant column heading. The Record List tab To make a new test, select the Record List tab. From this tab, you can register information about the patient and test. To start the recording, select (highlight) the test on the list and click the Record button.

Tests currently being recorded are marked with a symbol in red as shown.

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A file can be selected and reviewed in the Reader while it is being recorded. To do so, select the test on the Record List tab and click the Review button.

When you have completely finished the recording process, the test is ready to be moved to the Review List tab. Select the test and click the Move > button to transfer the recording from the Record List tab to the Review List tab. The Review List Tab Click the Review List tab to display a list of all tests awaiting review. Select a test and click the Review button to open the test in the Nervus Reader.

When you are completely finished reviewing the test, choose the Move > button to transfer the test to the Archive List tab. The Archive List Tab Choosing the Archive List tab displays a list of completed tests awaiting long-term storage or archiving. Click the Archive button to have Nervus Study Room perform the archiving operation on a selected test.

Archived tests can be reviewed in the Nervus Reader. Archived Tests Read Only

All documents belonging to an archived test are marked as “read only” in the file system.

Reading from Archived Media

The system remembers the last known path to the archiving medium.

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Multiple selection of tests Multiple selection of tests in the Study Room makes it possible to select more than one test at a time and perform various operations to them all at once.

The operations supported in multiple selection include: move between workflow tabs, delete, review, unmark recording status, reassign test to a patient, prune and archive.

Hold down the Shift or Ctrl key to select multiple tests.

Fixed command buttons On the right of the Study Room interface is the Commands section with fixed command buttons. Availability of these buttons depends on the tab currently selected and on the record selected on the tab. Moving between tabs The Move buttons are used to move tests between tabs. However, the Move buttons are unavailable for a newly created test until it has been recorded and closed. Move buttons

When you click Move >, Nervus moves the test record onto the tab to the right. Move Right becomes available when a recorded test record is selected, and there is at least one tab to the right.

When you click < Move, Nervus moves the test record onto the tab to the left. Move Left becomes available when a recorded test record is selected, and there is at least one tab to the left.

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Record button Record becomes available when a test record for which no recording has been made is selected. When you click Record, Nervus starts the Nervus Recorder, and you can proceed to record the test. See “The Nervus Recorder”, chapter 5. Review button Review becomes available when a test record for which a recording has been made is selected. When you click Review, Nervus starts the Nervus Reader where you can review the EEG test. See “The Nervus Reader”, chapter 6. View Report button View Report becomes available when any test record is selected. If HTML Reports are enabled (in the Administration Center), Nervus creates a Report in HTML format and opens it in the Report Editor. Otherwise, Nervus starts a document wizard which will create a report as a Microsoft Word document. Nervus suggests a document title which you can accept or change. When the title is the way you want it, click Create, and the wizard will generate the report. Thereafter, when you click View Report, Nervus will open this document in Microsoft Word or Report Editor if HTML Reports are enabled. View Referral button View Referral becomes available when any test record is selected. If HTML Reports are enabled (in the Administration Center), Nervus creates a Report in HTML format and opens it in the Report Editor. Otherwise, Nervus starts a document wizard which will create a Microsoft Word document. Nervus suggests a document title which you can accept or change. When the title is the way you want it, click Create, and the wizard will create a Word document with this title. Thereafter, when you click View Referral, Nervus will open this document in Microsoft Word or the Report Editor if HTML Reports are enabled.

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Archive button Archive becomes available when any test record in the Archive list is selected. Clicking this button starts the Nervus archiving procedure with the Archive dialog.

Remove local copies: after archiving is completed, Nervus will remove the local copy of the test from the user’s defined Work Area.

When you click OK in the Archive dialog, Nervus displays the Insert Medium dialog. Here you select the storage medium for the archived test. Click the arrow next to the Device field to open a drop-down list of available storage devices.

Note: see the Archiving chapter for full instructions on archiving. Refresh button Click Refresh to update the display.

4.2 Menus and Toolbar commands

The upper part of the Study Room interface is devoted to the menus and toolbar commands. You can access all the Nervus Study Room functions from the menus. The seven buttons beneath the workspace menus provide convenient, quick access to the functions needed most often.

File Menu: New Test

To create a new test record and add it to the list on the Record List tab, choose New Test on the File Menu or click the New Test toolbar button.

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Enter New Patient If the patient has not been registered previously, choose New Patient, and click on the Next button. The wizard displays the Enter New Patient dialog:

Fill in patient information as appropriate, then click Next to open the Test Info dialog.

Patient ID Any identification information may be used, for example, a national ID number or a number assigned by the hospital.

Last Name The patient’s last name. First Name The patient’s first name. Middle Name(s) The patient’s middle name(s). Given Name The patient’s given name. Address The patient’s address. Date of Birth The patient’s date of birth. Telephone The patient’s telephone number. Sex Choose from the drop-down list box. Hand Dominance

Indicate the patient’s dominant hand.

Patient Notes Here you can type additional notes about the patient.

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Existing Patient If you want to create a new test for a previously registered patient, choose Existing Patient, enter name or patient ID to narrow the search and click the Search button. Choose a patient from the list and click Next to open the Test Info dialog.

Or you can skip this step by right-clicking a test in the Study Room and choosing New Test for this Patient. Test Info After you have completed either the New Patient or Existing Patient options, the Test Info dialog will be displayed. Select or type information about the test:

Type Select from the drop-down list box. The default is Routine EEG. The other options are Long-Term Recording, HTP Recording and Ambulatory.

Test ID Required. Here you type appropriate information to identify the test.

Requested by The name of the physician requesting the test. Medication If the patient is under the effect of medication,

you can note the name(s) here. Patient State Here you can type a brief indication of the

patient’s state prior to the recording. Test Notes Here you can type additional notes about the test.

After you have completed the New Test Wizard, click Finish and the test is added to the list on the Record List tab.

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File Menu: Open Test

This command opens the Test Properties dialog for the selected test. Alternatively, right-click the test and choose Open Test from the pop-menu.

The dialog contains 3 tabs holding information related to the Test, Patient and Documents associated with the test. The information displayed comes from the Nervus Database.

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Properties tab fields Test ID The test identification. Type The type of test. Referring Phys The physician referring the patient. Technician The technician who recorded the test. Patient State The patient’s state prior to the recording. Medication The patient’s medications are noted here. Test Notes Notes made by the recording technician . Recording Date The date the test was recorded. Recording Start The time the recording was started. Recording Stop The time the recording was stopped. Length The total time of the recording. EEG File Path to the EEG file where the test data are

recorded. Patient tab fields The information on this tab is exactly the same as on the Enter New Patient dialog. Documents tab fields The contents of this tab vary. For example, the Test Report generated by the Nervus Study Room will appear here along with any other objects associated with a test. Custom reports Custom reports in any format can be inserted into the Documents tab of the Test Properties dialog. This feature can be used to include, for example, bitmaps, video, voice-annotated reports or MRI scans to the documents folder for a particular test.

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To create a custom report: 1 Click New to open the Document Wizard: 2 Select the Custom option. 3 Click Next to open the Insert Object dialog:

From the Insert Object dialog, you can either create a new document or select an existing file. To create a new document, select the Create New option button, then select the object type you want from the Object Type list. Click OK, and the appropriate application will launch to create that type of file. When you have finished creating the file, close it and the Document Wizard will prompt you to name your document. Fill in a name and click Finish to add the file to the list on the Documents tab.

To select an existing file, choose the Create from File option on the Insert Object dialog, then browse to select the file you want to insert. Click OK, and the file will be added to the list on the Documents tab.

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To open a custom report from the Documents tab, select the name from the list and click the Open button. This will open the report in the application that created it. Rename reports It is possible to rename a report from the Documents tab in the Test Properties dialog. To do so, open Test Properties by double clicking on a test in the Study Room, or by selecting the test and choosing the Open Test button. On the Documents tab, select the document that you want to rename and click the Rename button.

Fill in a new name in the space provided in the Rename Document dialog and click OK. View Clicking on this button opens a sub-menu con-

taining Test, Report and Referral. To review the test with the Nervus Reader, choose Test. To view a summary report of the test in Microsoft Word, choose Report. To review the referral document associated with the test, choose Referral.

Patient Folder Click on this button to open the patient’s folder.

Admin Clicking on this button opens a sub-menu of administrative functions. The Archive option

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enables you to transfer the test to permanent storage at some location on the network or onto a CD-ROM. The Prune option starts the Prune Settings dialog where you can delete all portions of a recording you do not want stored. Delete Online deletes the EEG test file permanently, provided the file has already been archived.

File Menu: Print

Patient and test lists can be printed from any window or dialog in the Study Room using the Print command.

File Menu: Log off

Choosing this option opens the Log Off dialog. You can use this dialog to Log off, Restart, Shut Down, or Shut Down Study Room.

Note: Shut Down Study Room is an option in the Nervus program. Log Off, Restart and Shut Down are Windows options for the whole system.

Choose OK when the desired option is selected.

Note: the Nervus Study Room status bar shows the current user.

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View Menu

This menu enables you to display or hide the workspace’s graphical elements. A check-mark next to the item indicates that the Nervus Study Room is displaying the element.

Tools Menu: Find Tests

Choosing this option opens the Find Tests dialog below:

Using this dialog, you can have Nervus create a list of tests which meet criteria that you specify. You can specify criteria on each of the tabs in the dialog. After specifying your criteria, start the search by clicking Search.

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Here is a run-down on the criteria you can specify on each tab: Search by Test Test ID By default this field is blank, meaning Nervus will

return all test IDs meeting other criteria on the tabs. However, you can type the test ID for the test you want or just the first few characters of it. The search will then return any test where the test ID begins with the string you typed. The more characters you type, the more limited the search. By typing the complete test ID, you can limit the search to return a single test.

Test Type The default is to include all test types in the search (“Any type”), but you can limit the search to one type by selecting it from the drop-down list.

Test State The default is to include all test states in the search (“Any”), but you can limit the search to one state by selecting it from the drop-down list.

Requested by

You can type a specific referring physician’s name here to limit the search to tests requested by the physician. The search will return any test where a referring physician’s name begins with the letters you typed.

Search by Recording You can further refine your search by choosing the Recording tab. The following fields are displayed:

Period The default is All, but you can limit the search to a pre-defined period by choosing it in the drop-down list box–for example, This Week, Last Week, This Month, etc.

Specific Choose this option and type a date into the field to limit the search to tests recorded on a specific date.

Recorded by The default is Any user, but you can choose a specific person from the drop-down list box to limit the search to tests recorded by this person.

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Search by Media You can further refine your search by choosing the Media tab. The following fields are displayed: Any Choose to include all storage media in the search. Online Only Choose to include only online media in the

search. Online and Offline

Choose to include both online and offline media in the search.

Offline Media Choose to include only offline media in the search.

When you have entered your search criteria on the dialog tabs, click on Search to initiate the search. Nervus displays the search results in a list below the criteria, sorted on the Test ID field in ascending order. You can re-sort the list, using any of the column headings as a key. Clicking once on the column heading re-sorts the list in ascending order. Clicking again on the same heading will re-sort the list by the key in descending order. Search by Patient The Patient tab in the Find Tests dialog allows searching by patient name and ID in addition to all the fields currently available in Find Tests. This can be used, for example, to search for all tests recorded before a certain date belonging to a specific patient.

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Tools Menu: Find Patients Choosing this option opens the following search dialog:

The dialog enables you to search for patients whose last names begin with the characters in the string you type in the Last Name field. Thus, the string “Jon” would return tests for patients whose last names begin with that string: Jones, Jonsson, Jonas, etc. You can narrow the search by typing more characters. Click on the Search button to start the search. Nervus displays the search results in a sortable list below the criteria, sorted on the Patient ID field in ascending order. You can re-sort the list, using any of the column headings as a key. Clicking once on a column heading re-sorts the list in ascending order. Clicking again on the same heading will re-sort the list by the key in descending order.

After locating a patient, you can open the folder by double-clicking on the record in the PatientID column in the Find Patients dialog, or by clicking the Patient Folder toolbar button.

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Tools Menu: User Administration Choosing this option opens the User Administration dialog. Here you can add a new user to the list in the Log on Information dialog, or you can change the status of a user from active to inactive.

To create a new user: 1 Click on New User. 2 Fill in the user’s name and job title. 3 Select Type for type of user (Administrator, User or Guest). 4 Click OK.

The user’s name will now appear on the list in the User Name box when the appropriate option is selected in the Users section at the top of the dialog.

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Delete: to delete a name, select it from the list in the Username box and click Delete.

Change Active/Inactive Status: to change a user’s status from Active to Inactive or vice versa, select the name from the list in the Username box, and select Type from the dropdown list.

Note: when a user’s status is changed to Inactive, the user will not be able to logon to the Study Room. Tools Menu: Register Starts the Nervus registration procedure to register EEG files in the Nervus database. You use this procedure, for example, for EEG files recorded under a previous version of Nervus. Nervus will display a dialog asking you to indicate the file location:

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Use the browse feature to locate the file you wish to register, click on it, and choose Open. Nervus will open the New Test Wizard, where you can register the file to the Nervus database. If the file being registered comes from another database and already contains Test and Patient information, the New Test Wizard is not shown, but the information from the file is used to create a new test and patient in the Nervus database. Tools Menu: Settings This is a utility used mostly by the system administrator. See chapter 7. Tools Menu: Administration Center This is a utility used mostly by the system administrator. Work Area

On the Work Area tab of the Administration Center, you can select the location where recorded files will be stored. Click Add to add a new Work Area and assign it a priority rating. The Work Area with the highest priority (lowest number) is the one that will be used.

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Use the Advanced button to allow the use of the local recording area as a Work Area. The files are then not moved from the local recording area until the test has been archived or pruned. This feature is of particular benefit to those users who are doing long recordings and do not want to overload a slow network unnecessarily. Devices This is where you add in devides available on your PC or the network. See Archiving, chapter 8. Study Types You can configure which study types are available on the Test Type listbox in the New Test Wizard. Select a test from one of the lists on the Study Types tab of the Administration Center (Tools > Administration Center) and click one of the arrow keys to move it to the other list. The list marked “Selected” will show up on the Test Type listbox.

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Type in a name for the test type and an abbreviation to refer to it. In the Recording section of the dialog, choose External Recording from the drop-down list for Recording Application. Browse for the application you want to automatically launch when a test of that test type is selected in the Study Room and the Record button is clicked. Under the Reviewing section, select the application that you want to use to review tests that have already been made. This application launches when the test is selected in the Study Room and the Review button is clicked.

When the Monitor Application checkbox is selected, Nervus will prompt you with a dialog when the recording or reviewing application is closed.

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Select this option under the recording section to have Nervus automatic-ally mark the test as Recorded in the Study Room.

Under Recording Application, it is also possible to select “none”. This is to create a study type to address visits the patient pays to the hospital that do not produce any test file. Information is stored in the Study Room, but no external application is associated with the test type. For some Applications it is possible to select the Protocol (Record or Review) to be used when a test of the type is opened. Version information A record of the version numbers of the software currently in use are listed. This list can be printed if this information is required for support issues. Environmental variables This tab in the Administration Center displays such things as the location of the documents working directory, workspace folder, and whether or not the unique patient ID is enforced. External databases Connection to external Nervus databases can now be managed via the External Database tab in the Administration Center. To add a database to the list, click the Add button to open the External Database Properties dialog:

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Name refers to any user definable name such as Research Database. The ODBC Name refers to the name of the data source defined under System DSN in the ODBC applet, for example, RESEARCH.

ODBC Connect string refers to the path for the data source, for example. f:\database\taug.mdb, again defined under System DSN in the ODBC applet. After filling in the information, click OK. When the Log Off button is clicked in the Study Room, the dialog now gives users the option of logging onto the external database. Test Menu: Review

Choose Review to have Nervus display the Review Options:

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Note: the following sub-menu options are available only if you have selected a record in the Nervus Study Room:

Test Opens the selected EEG test in the Nervus Reader. Report Opens the latest copy of the Microsoft Word report about

the selected test. Referral Opens the latest copy of the Microsoft Word referral

document. Test Menu: Patient Folder Choose Patient Folder to have Nervus display the contents of the patient folder in which the selected EEG test is stored.

A patient folder stores all EEG tests and other documents for a particular patient. To open a patient folder for a test on the Record List tab, Review List tab or Archive tab: 1 Select the record by clicking on it once in the Test ID column. 2 Click on the Patient Folder button. Or you can press the right mouse

button and select Patient Folder on the pop-up menu. Nervus will open the patient folder where the record has been stored:

When you select a patient object in the folder, the View, Open Test and Admin buttons become available.

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View

Test Opens the Nervus Reader and displays the relevant EEG test data.

Report Starts a wizard to generate a report on the EEG in Microsoft Word. This report’s format is governed by a Word template (*.dot).

Referral Opens the latest referral generated in the main Nervus Study Room dialog with the View Referral button.

Test Menu: Prune When you have viewed the original recording, you can prune it down to the events and/or the part that you would like to keep.

Choose the Prune command under Admin on the Test Menu to open the Prune Recording dialog:

Select a Prune Template from the list and click OK to prune the test according to the parameters specified in that template.

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To create a new template: 1 Click New and type in a name for the template. 2 Select events that you want to keep from the event list on the left

and move them to the list on the right using the right arrow button (remove them again using the left arrow button).

3 Select an event in the right event list to fill in how many seconds before and after the event you want to keep.

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Test Menu: Admin Choose Admin to have Nervus display the Administrative options:

Reassign patient to test To reassign a patient to a test within the Study Room, choose that option under Admin on the Test Menu. Search for the patient by filling in a few letters of the patient’s first or last name or patient ID and clicking on Search. Select the patient from the list that appears and click OK to assign that patient to the test. This feature is useful in case a recording was mistakenly taken on a test with another patient’s name.

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Detection The automatic detection functionality offers the user the ability to select from a variety of automatic analyses to run as background tasks in the Study Room. (Detections can also be performed in the Recorder and Reader).

To perform an automatic detection: 1 Select a recorded test by clicking on it on the Review List tab in the

Study Room. 2 Choose Detection on the Test Menu to open the Detection Settings

dialog. 3 Highlight a Detection Template from the list and click OK.

While the detection process is taking place, an hourglass appears in front of the test in the Study Room. This indicates to others on the network that the test is currently in use. This will disappear once detection is completed.

For information on creating or modifying Detection Templates, see the Detections section of the Settings chapter.

Note: the Detections functionality is an optional feature.

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Workspace Menu

Create shortcuts on the Workspace Menu to EEG tests of interest for conferences, training etc. Choose Workspace > Add to add a test to any workspace folder. Any number of folders can be created (by clicking the Add Folder button) to allow quick and easy access to the EEG test of your choice.

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4.3 Networking

Any Nervus system can be removed from the network to be used as a stand alone system. On re-connecting the system to the network, EEG data is automatically updated to the main database. The system must be turned off when removing from or re-connecting to the network.

A Nervus system connected on the network to a main database will show the message “Main Database’’ in the bottom right hand corner of the Study Room.

On a system disconnected from the network, ‘‘Local Database’’ will be shown together with a yellow square in the Study Room.

4.4 Windows Explorer

Patient Fields in Windows Explorer

Add columns to the Windows Explorer to make it easy to get patient and text information of EEG files.

In the Windows Explorer, select View menu>Choose Details (in Windows 2000, choose View>Column Settings) to open the following dialog.

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In the list there are several EEG file specific choices: Patient ID, Patient Name, Patient DOB, Test ID, Test Start Date, Test duration, Technologist, Physician, and Patient Notes. Check the items you wish to display in the Windows Explorer and click OK.

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5.1 Overview

The Nervus recorder provides a range of features to assist you with a recording session’s routine operations and its unexpected events. The toolbar and panel buttons allow point-and-click control of the acquisition of up to 128 EEG channels, synchronous digital video, montage selection, filtering, photic sequences, hyperventilation, trend analysis and spike and seizure detection. You can mark user-defined events quickly and accurately with the customizable event palette.

5.2 Recorder interface components

The Nervus Recorder offers a convenient, customizable graphical interface. Following is the Nervus Recorder window with its main features displayed:

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The Recorder Interface window

Key: 1 Menus 2 Toolbar 3 Overview 4 Trace Labels 5 Review Pane 6 Review Event Palette 7 Live EEG Pane 8 Live Event Palette 9 Panel 10 Movable Split Bar 11 Status Bar

1 2

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The Trace display The EEG trace display makes up the main part of the Recorder interface. The window is divided into two panes by a movable split bar. Drag the bar to either side to adjust the size of the panes. Live Pane The Live Pane shows you the EEG traces in real time in both the preview and record modes. You can mark events in the live pane as they occur or indicate segments where you want to add annotations. Review Pane The Review Pane displays the recorded trace curves from the beginning up to the current position in the recording session. Use this pane to review previous parts of the recording and perform some editing to mark events and add annotations. Navigating the Review Pane To navigate through the recorded EEG traces on the Review Pane, use one of the following four methods:

1 Click on the trace display. When the cursor is positioned over the trace display, it changes into one of four different arrow cursors, depending on its position on the review pane:

Far Left cursor becomes large, left-pointing arrow. Click to page back one page.

Left cursor becomes small, left-pointing arrow. Click to page back 1/2 page.

Right cursor becomes small, right-pointing arrow. Click to page forward 1/2 page.

Far Right cursor becomes large, right-pointing arrow. Click to page forward one page.

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2 Drag the thumb markers on the Time Scale overview. 3 Use the following keyboard shortcuts: Home Go to beginning of recording End Go to end of recording Left Arrow Step left one second Right Arrow Step right one second Page Down Go forward one page Page Up Go back one page 4 Drag the Zoom Overview. Event palettes There are two event palettes that can be used to insert events into a recording. (See figure 1)

The Live Event Palette is a vertical strip on the right side of the Live EEG pane that contains the currently available user-defined events. These events can be inserted into the Live EEG pane.

The Review Event Palette appears to the right of the Recorded EEG pane and contains events that can be inserted into the Recorded EEG pane.

See the Events section for information on inserting events. See the Event Type Editor section in the Settings chapter to create or modify event markers. See the Event Palette Editor section in the Settings chapter to select or define a new palette of events.


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View Menu

The View Menu is used to control the display of the main visual elements of the program. A check mark indicates that the item is visible. Click once on the command to remove the check mark and hide the item from view.

Tip: hide elements such as the toolbar or panel to increase the size of the trace display. Most of the controls can still be accessed via the menus or shortcut keys. See the appropriate section for each control to find out the alternate way of accessing it.

Toolbar When Show is checked on the Toolbars submenu of the View Menu, the main toolbar appears across the top of the Recorder window just under the menus. Select Label on the submenu to show button names as well as the icons. The following list shows a picture of each toolbar button, followed by a short description of its function and the menu where you can access the command if the toolbar is not displayed.

Record: start recording data to disk. Acquisition Menu.

Record: display EEG traces in real time without recording to disk. Acquisition Menu.

Deblock: trigger deblock on the amplifier. Acquisition Menu.

Impedance: open the Impedance Test dialog in the right pane of the Recorder window. Acquisition Menu.

Video: start recording video. Press again to stop. Video Menu. Note that the Record button must also be active for video recording to take place.

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Selective: record video only when user-defined events occur. Video Menu.

Notch: apply notch filter. Format Menu.

Settings: open the Edit Settings dialog in the left pane of the Recorder window. Format Menu.

Overview: display the overviews selected on the overview submenu of the View Menu.

Review: Toggles the Review Pane on and off in the Recorder. The size of the panes is still adjusted by dragging the split bar as before.

End: Press this button to jump to the end of the recording in the Review Pane

Panel: display panel if hidden, or hide panel if showing. View Menu.

Montage: easily switch between 5 common montages:

Status Bar The Status Bar appears at the bottom of the Recorder window when it is selected in the View Menu. The Status Bar displays two clocks. The one closer to left shows the time since the last montage change, the other shows the total recording time. Both clocks show time in the following format: date:hour:minutes:seconds.


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A green bar is displayed on the right side of the Status Bar when a test is in preview mode. A red bar is displayed on the right side of the Status Bar when a test is in record mode. A blue bar is displayed when impedance is measured.

A green, red or blue rectangle to the right of the clocks on the Status Bar indicates Previewing, Recording or Impedance test respectively.

Panel The Panel appears on the right side of the Recorder window when Show is checked on the View > Panel submenu. The items checked on the submenu are displayed.

Individual parts of the Panel can be expanded or contracted by clicking on the title bars of each tool. Each part can also be made into a floating palette by clicking the arrow button to the left of the title. Click again, or click the palette’s close box to dock the palette back into the Panel.

Note: the list of individual parts of the Panel on the Panel submenu varies depending on settings configurations and whether hardware such as a video camera or photic stimulator are connected to the computer.

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Format panel The Nervus Recorder is flexible in the way it displays EEG data. You can create custom montages and quickly change between format settings. You can also save a group of settings as a protocol, so you can easily select the same protocol later for a similar type of recording.

The Format control on the Panel is used to quickly switch formatting and apply filters. Montage Montaging is about describing and calculating a linear mapping from the raw, acquired data. You can create a custom montage with the Montage Editor containing specified channels with defined properties, such as filters or display type.

Montage selection: you can quickly switch between montages by using the Montage Selector in the Format Panel, or by choosing one on the Format Menu.

Montage editor: add a custom montage to the Montage Selector by using the Montage Editor. (See the Montage Editor in the Settings chapter for information on doing this.) Timebase (paper speed) The Timebase control (on the Format Panel or the Format Menu) has an effect on how fast the traces scroll by as they are being displayed on the Live EEG pane. In effect, this is the virtual paper speed.

You can set the Timebase to display millimetres per second or seconds per screen. (See View Settings, in the Settings chapter to do this.)

If using mm/sec, a higher value will appear to scroll faster. If using sec/screen, a lower value appears to scroll faster.


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Sensitivity Use this control on the Format Panel, or on the Format Menu, to select a sensitivity setting for all channels in the current montage not marked as special. The sensitivity describes the number of microvolts in each milli-meter or centimeter vertically on the screen. Select Tools > Options > Regional to select the unit of sensitivity. Deflection Use this control on the Format Menu, to select a deflection setting for all channels in the current montage not marked as special. Deflection describes the vertical measurement of a trace before it is cut off.

Note: this control is not included on the Format Panel High frequency filter Apply the High Cut Filter using the Format Panel, or the Format Menu, to all channels in the current montage not marked as special. Low frequency filter Apply the Low Cut Filter using the Format Panel, or the Format Menu, to all channels in the current montage not marked as special. Special channels You can mark a channel as special by using the Montage Editor (see Montage Editor in the Settings chapter) or by right-clicking on the channel on the live pane trace display and choosing special from the menu. Special channels are not affected when formatting settings such as filters are applied using the Format Panel or commands on the Format Menu.

Note: if a channel is marked Special by right-clicking on the channel on the trace display, the setting won’t be saved into the current montage unless you choose Save in the Montage Editor.

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Photic panel Note: a photic stimulator must be connected for this panel to be dis-played.

The Photic panel is used to control the Nervus Photic Stimulator. You can play a programmed photic sequence (see Photic Editor in the Settings chapter to program a new sequence), or select a single line of the sequence to play. Or you can press a button to manually administer a single photic flash.

An event marker is inserted automatically to mark photic stimulation events.

To play a photic sequence or a line from the sequence: 1 Select a photic sequence from the Sequence list. 2 Browse to the line that you want the sequence to start on/play.

Press the Start button to start the photic sequence; press again to stop.

Press the photic line button to play the single line.

Press the Reset button to set the sequence back to the beginning line. If you press Reset while the sequence is running, the sequence stops and resets.

Press the Flash button to administer a single photic flash.

Hyperventilation panel The Hyperventilation section of the Panel is a stop watch to aid hyper-ventilation and is used to mark hyperventilation events. The event markers are inserted automatically into the trace display when the Hyperventilation tool is used.

Click the Start button to insert a “HV Start” duration event. Click the Stop button to insert a “Post HV” duration event. Click the Reset button to close any open HV event and reset the clock to 0.


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Event list The event list is a tool used for analysing or editing a recording by its events. Following is a list of ways to use the event list: Jump to event Click on any event in the event list and the trace display automatically jumps to that point in the recording.

If you scroll to a new page in the recording, the first event on that page is highlighted in the event list. Sort The event list can be sorted by event name, time or duration by a simple click on the column header. Click the header a second time to reverse the order. Delete To delete events from the list (and the recording) select the event and press the Delete key, or right-click the mouse and choose Delete from the popup menu. Print

Click the Print button to print the currently visible list of events. The printed output includes: l Test ID l Patient name l Logged on user l Date and time of export

Export

Click Export to export the list to a text file (including the above list).

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Reaction time stimulator The Reaction Time Stimulator is used to measure a patient’s reaction time. A stimulus is administered and the patient reacts by pressing a button. The amount of time between the stimulus and the reaction time is measured and an event with this information is inserted into the trace display.

Select a type of stimulation from the list: photic, audio or external. The external choice refers to an optional device, such as a sound generator, connected to the computer.

Press the first button to administer a single stimulus manually.

The second button starts random stimulation. Press the button again to stop random stimulation.

The third button administers stimulation triggered by a spike or the beginning of a seizure. Trends panel The Trends panel is used to switch between Trend Templates and change the display of the Trend Overview. 1 Select a Trend Template from the Trend list. (Trend Templates are

created using the Trend Editor; see the Settings chapter for information.)

2 Duration determines the length of time displayed at one time in the Trend Overview. This is similar to using the Zoom Overview to zoom in a part of a recording.

3 Select a trend type from the list. 4 Choose a minimum and maximum envelope in microvolts.

Notes: The Trend panel controls trends that have not been marked as special. Trend Analysis is an optional feature.


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Montage View panel The Montage View panel shows a quick view of the current montage. Click the Float button (in the left corner of the Montage View title bar) and drag a corner of the window to increase its size and show the numerical positions of each channel.

Video panel The Video panel displays synchronous video as it is being captured. Click the Float button (in the left corner of the Video title bar) to display video in a floating palette, in the resolution used in capture.

Note: a video card and camera must be connected for this panel to be displayed. See the card’s accompanying documentation for instructions on capture settings.

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Overview The Overview allows you to quickly locate interesting parts of the recording. The Overview uses a time scale that is (usually) much larger than the one used in the review pane.

Select Overview > Show on the View Menu to display the Overview. Several overviews are available in the Recorder. To choose the overviews you want displayed, select them on the Overview submenu, or right-click the overview to select items on a pop-up menu. The overviews appear across the top of the Recorder window, just under the menus and toolbar.

Other options available on the Overview submenu are the following:

Label Bar: choose Label Bar to show the name of each displayed overview at the left edge of the overview. Gridlines: choose Gridlines to display a grid in the background of the overview. Elapsed Time and Time of Day: choose one of these options to determine how the Time Scale overview marks the time.


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Time Scale overview

The Time Scale overview marks the time of the recording and functions as an advanced scrollbar. Drag the thumb markers to scroll to a specific part of the recording.

One of the following two methods of marking the time can be used: Time of day The absolute time when the recording was made. Elapsed time Beginning at 0 when the recording starts and

ignoring delays between segment stop and start.

To choose one of these methods, right-click the overview and select the method you want from the pop-up menu, or access this menu by choosing View > Overview. Event overview

The Event overview shows a graph with color-coded bars indicating the time of all events, including user-defined events from the event palette, or automatically inserted events such as Hyperventilation and Photic events. Video overview A horizontal line indicates that video is available for the recorded data. If the cursor is placed over the line, a tooltip appears displaying information about the video segment (start time and duration). Zoom overview

The Zoom overview allows you to “zoom in” on just a part of the recording, or view the entire recording in one screen.

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Drag either end of the zoom bar to shorten it and decrease the amount of the recording displayed in the Overview, or select a length of time by choosing View > Overview > Zoom. Click and drag on the middle of the bar to move it right or left to the part of the recording you want to view. While dragging or resizing the Zoom bar, a tooltip appears displaying its position in the recording and its length. Trend overview

The results of a trend analysis can be displayed as an overview. Click a point on the Trend Overview to jump to that point in the review pane.

Click on the Trend labels and drag to shuffle the placement of the trends around. Mouse over a trend to display a tooltip with the actual value of the trend trace. Mouse over the trend label to display the type of trend. Drag the lower edge of each trend to resize.

Right-click a Trend Overview to display a popup menu with two options: Scaling The scaling option allows you to change the minimum and

maximum values of the vertical axis of the trend, which are stored in the current trend template.

Special Choose this to toggle the Special flag on or off. Trends marked as special are not affected by the Trend Panel.

Notes: To display the Trend Overview, a Trend Template must be part of the currently selected protocol. See the Settings chapter for information on protocols and how to use the Trend Editor to create a Trend Template. Trend Analysis is an optional feature.


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5.3 Acquisition

The Nervus Recorder allows acquisition of up to 128 EEG channels, as well as synchronised digital video, at the click of a button. Before you start recording data to disk, it is recommended that you preview the live, online traces and perform an impedance check to make sure that all electrodes are properly in place and functioning.

Preview When the program starts, preview of EEG traces is started. The right end of the Status bar shows a green bar indicating that previewing is in progress and no data is being saved to disk. The words Not Recording are displayed on the trace display.

Impedance test

Click the Impedance toolbar button or choose Impedance on the Acquisition Menu to perform an Impedance check.

The Impedance Test dialog, pictured below, is displayed in the right-hand pane of the Recorder window and a blue bar is displayed in the status bar.

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The impedance of each channel is measured and compared against the threshold value selected in the Threshold list. Color-coding allows at-a-glance interpretation. Green Impedance is lower than the selected threshold value.

Electrode is properly connected. Red Impedance is higher than the value selected. Electrode

needs readjusting. No color The channel is not selected in the Amplifier Setup

dialog.


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Continuous impedance test Continuous Impedance Test is a heuristic for detecting bad electrode connections during an EEG recording. An advantage over the regular impedance test is that the recording does not need to be interrupted to perform the test. Also, since the test is automatic, it can detect loose connections when there is no technician present and trigger an alert through the Alerts feature.

To enable continuous impedance testing, make sure that option is checked in the miscellaneous section of the Edit Settings dialog. (See the Settings chapter.)

Perform a regular impedance test, as described in the section above, at the start of a recording. When impedance crosses the selected threshold, a high impedance event marker is inserted into the trace display.

To assign a method of notification to the event, see Alert Settings in the Settings chapter.

Record

Press the Record button on the Toolbar, or select the Record command on the Acquisition Menu to start the recording. The EEG data (and digital video if turned on) is saved to disk.

Recorded EEG traces are displayed in the Review Pane (the left pane) of the trace display.

A red bar on the right side of the Status Bar indicates that data is being saved to disk.

If the Record button is pressed after recording to disk is started (the button is down and there is a checkmark with Record in the Acquisition menu) then the data is not stored to disk and the Status Bar indicator will turn green as in Preview mode (see above)

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Video acquisition

Push the Video button on the Toolbar, or choose Save Video on the Video Menu, to record synchronous video. The Record button must be active (see the Record section above).

Click the Video button a second time to stop recording video.

Note: if you want to record synchronous video from the beginning of the EEG recording, make sure the Video button is depressed before clicking the Record button.

Selective video

Use the Selective Video button if you want to record video only when specified events occur. (See Video Settings in the Settings chapter for information on specifying events.)

Video Menu Save Video and Selective Video on the Video Menu correspond to the two Video toolbar buttons. You can also use this menu to configure the video source, format, display and compression settings.

Note: these dialogs vary depending on the type of video card you have installed in your system. Refer to the card’s accompanying document-ation for instructions on how to use these dialogs.


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Calibration Mode To record in calibration mode, make sure this command is checked on the Acquisition Menu BEFORE starting to record.

5.4 Protocol

Select a protocol

You can apply a whole group of settings, called a protocol, at one time by selecting the desired protocol from the Protocol Menu.

Save a new protocol Save the current configuration of settings by choosing Save at the top Protocol Menu. Type in a name for the protocol and click OK. The new protocol appears on the Protocol Menu.

The following settings are saved to the Recording Protocol: amplifier Setup, Sensor Group*, Montage*, Trend Template*, Event Palette, Alert Template, Detection Template, Photic Sequence, Video Template, Views, Frequency Analysis, File Format and Continuous Impedance Test (in Misc Settings), Format (Format Panel or Format Menu), Panel and Overviews (View Menu).

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5.5 Events

Event markers are used to mark moments or time intervals of interest in the recording. Examples are behavioral information about the patient, a clinically interesting waveform, notification of drug injection, or a text annotation.

Marking Events

Event Marker on Trace Display

Events can be marked in the Live EEG Pane as they occur using the Live Event Palette, or later into the Review Pane using the Review Event Palette. Marking events in Live Pane To insert an event into the Live EEG Pane, click an event in the Live EEG Event Palette, or use the corresponding shortcut key as defined in the Edit Settings, Event Palettes dialog. The event is automatically inserted into the Live Pane. Marking events in Review Pane To insert an event into the Review Pane, click an event in the Review Event Palette. The cursor changes into a pointing hand. Click with the pointing hand at the place on the Review Pane where you want the event inserted.


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Duration events

Duration Event Marker on Trace Display

Duration Events occur over a period of time, and are indicated on the trace display with a bar marking the length of the duration. Marking duration events in the Live Pane To mark duration events in the Live EEG Pane, click the event marker on the Live Event Palette once at the beginning of the event, and again to mark the end of the event. Marking duration events in the Review Pane To mark duration events in the Review Pane, click the event marker on the Review Event Palette. The cursor changes into a pointing hand. Click a trace on the Review Pane at the point where you want the event to begin, and again at the point where you want the event to end.

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If you need to scroll to get to the end point of the marker, move the cursor above or below the trace where you are inserting the event to change the cursor temporarily into the paging arrow. Scroll to the end point of the duration event. (You can also page using the arrow keys on the keyboard.)

Click the target area to close the event. The cursor changes back into the insert event mode as it nears the target trace.

Modify duration Right-click on the event marker and choose Resize from the popup menu. The cursor changes into a pointing hand. Click the display at the point where you want the duration to end. (see above section, Marking Duration Events in Review Pane.)


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Event editor Create custom event markers using the Event Type Editor. (See Event Type Editor in the Settings chapter for more information about customizing events.) Event palettes An event palette is the set of events available to the user at a time. You can create custom event palettes to use for different types of recordings. (See Event Palette Editor in the Settings chapter.) Automatic events Hyperventilation, Photic and Reaction Time event markers are inserted automatically into the Live EEG pane when these tools are used. Nervus can be configured to insert a High Impedance event marker when impedance crosses a predefined threshold. (See the section, Continuous Impedance Testing, page 23.)

5.6 Remote Control

This optional feature allows control of a recording from a remote computer connected via network.

On the remote computer:

1.The test title includes the string [REMOTE CONTROL]. 2. Interface components, i.e. the panel, can be displayed independently of the host computer. 3. New data is available every 10 seconds in the review pane and the recording clocks are updated in the same interval. 4. The video interface is disabled.

All data is stored on the host computer while recording.

To control a recording remotely, open the Study Room on the remote computer. Select a test currently being recorded (indicated by a red arrow) on the Record List tab. Click the Remote Control command button to open the test with remote control activated. Alternatively, you can right-click the test and choose Remote Control from the pop-up menu.

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A pop-up notification appears on the host computer to indicate that the test is being controlled remotely.

5.7 Keystroke shortcuts

Standard Windows Ctrl+ N - New

Other Ctrl+ R - Start recording Ctrl+ M - Start Preview Ctrl+ E - Stop recording Ctrl+ I - Impedance Test Ctrl+ D - Deblock Ctrl+ K - Record Video Ctrl+ G - Notch Filter Ctrl+ T - Edit Settings Ctrl+ Alt+ Enter - Toggle test info page End - Go to End of recording in the Review Pane Left Arrow - Step left one second in the Review Pane Right Arrow - Step right one second in the Review Pane Page Down - Next Page in the Review Pane Page Up - Previous Page in the Review Pane Ctrl+ H - Next High cut filter Ctrl+Shift+ H - Previous High cut filter Ctrl+ L -Next Low cut filter Ctrl+Shift+ L - Previous Low cut filter Ctrl+ A -Next Paper speed value Ctrl+Shift+ A - Previous Paper speed value Ctrl+ B - Next Sensitivity value Ctrl+Shift+ B - Previous Sensitivity value Ctrl+ J - Start Photic Ctrl+ F - Flash Photic Esc - Stop Photic Ctrl+ Y - Start/Stop Hyperventilation Ctrl+ W - Toggle Panel


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Events Events are assigned to the function keys, F3 - F10 and SHIFT+ F2 - F12. This is done in the Event Palette editor according to the order of the event in the Palette.

Montage Montages can be assigned to the keys Ctrl+ 0 - Ctrl+ 9. This is done in the Montage Editor

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6 The Nervus Reader

6.1 Introduction

The Nervus Reader provides options for reviewing, analysing, annotating and printing an EEG file. Recordings can be automatically registered into the Nervus system or imported at a later stage from various sources. You can review a recording using any montage or filter settings and quickly switch it back to the as-recorded state. The Reader also offers powerful tools for analysing data and generating reports in various Windows-based applications.

With the Nervus Reader, you have two main methods of reviewing EEG recordings: As Recorded using exactly the same montage settings as when

the recording was made. Reformatted using montage settings other than those in effect

when the recording was made. Reformatting is performed by selecting options on the Format Panel or the Format Menu, or by modifying the settings of the current montage. (See the Montage Editor section in the Settings chapter). Switch back to the as-recorded state by simply clicking the As Recorded toolbar button. The current montage and format settings are shown at the bottom of the main window.

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6.2 Nervus Reader interface components

This figure shows the basic elements of the Nervus Reader window.

Key: 1 Menus 2 Toolbar 3 Overview 4 Trace Labels 5 Event Marker 6 Trace Display 7 Event Palette 8 Panel 9 Status Bar

1 2

3

4 5

6

7

8

9

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6.3 Navigating through a recording

There are several ways to navigate through a recording. You can use automatic paging with or without audio enhancement. Or you can step through the recording a page at a time. You can even go directly to a specific point or event.

Following are the various methods of navigation. 1 Use the Right and Left paging buttons on the toolbar (or the paging

commands on the Navigate Menu) to start automatic paging. Click again on the buttons to stop paging.

Automatic paging buttons

The speed can be adjusted using the slider on the toolbar. Press the Audio toolbar button (or select Audio on the Navigate Menu) to start the audio.

Speed adjustment

Audio button

2 Click on the trace display with the cursor to page a step at a time.

The cursor changes into one of four different arrow cursors, depending on its position on the review pane:

Far left Large left-pointing arrow. Click to page back one page.

Left Small left-pointing arrow. Click to page back 1/2 page.

Right Small right-pointing arrow. Click to page forward 1/2 page.

Far right Large right-pointing arrow. Click to page forward one page.

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3 Use the following keyboard shortcuts:

Home Go to beginning of recording End Go to end of recording Left Arrow Step left one second Right Arrow Step right one second Page Down Go forward one page Page Up Go back one page 4 Drag the thumb markers on the Time Scale overview, or click on a

point on the Trend Overview. 5 Click an event on the event list to go to a specific event in the

recording. Patient and test properties The patient and test properties can be accessed and edited at any time while a recording is open in the Reader.

Choose Patient Properties or Test Properties on the File Menu to open the dialog boxes in the Reader window.

Events Event markers are used to mark moments or time intervals of interest. Examples are behavioral information about the patient, a clinically interesting waveform, notification of drug injection, or a text annotation. The event palette, located on the right side of the trace display, contains the current set of user-defined events. See the Event Type Editor and the Palette Editor in the Settings chapter, for information on creating and modifying event markers and palettes.

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Marking events To insert an event into the trace display, click an event in the event palette, or use the corresponding shortcut key as defined in the Event Palettes dialog. The cursor changes into a pointing hand. Click with the pointing hand at the place on the trace display where you want the event inserted.

Event Marker on Trace Display Duration events Duration Events occur over a period of time, and are indicated on the trace display with a bar marking the length of the duration.

Duration Event Marker on Trace Display

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To mark duration events: 1 Click the event marker on the event

palette. The cursor changes into a pointing hand.

2 Click on the trace display at the point where you want the event to begin, and again at the point where you want the event to end.

If you need to scroll to get to the end point of the event, move the cursor above or below the trace. The cursor changes into the paging arrow. Scroll to the end point of the duration event. Or page using the arrow keys on the keyboard.

When you click the target area to close the event, the cursor changes back into the insert event mode as it nears the target trace.

To modify duration events: Right-click on the event marker and choose Resize from the popup menu. The cursor changes into a pointing hand. Click the end point of the event (see above instructions).

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Event editor Create custom event markers using the Event Editor in the Edit Settings dialog. (See Event Type Editor in the Settings chapter for more information about customizing events.) Event palettes An event palette is the set of events available to the user at a time. You can create custom event palettes to use for different types of recordings. (See Event Palettes in the Settings chapter.)

6.4 View Menu

From the View Menu you can change what features Nervus displays in the Reader window by selecting that item. Checked elements indicate what Nervus is displaying. To hide these elements from view, uncheck them by selecting them again in the menu.

Toolbar Select Show on the Toolbar submenu to display the toolbar.

Select Label to show the names of the buttons in addition to the icons.

On the next page is a description of the individual items on the standard Reader toolbar. From the toolbar you can access most basic functions of the Reader.

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Save

Saves the changes to the file.

Print

Prints the currently displayed page.

Paging buttons

Click these buttons to play the recording back-ward or forward. Click them a second time, or

simply click anywhere on the trace display, to stop the playback. Double-click the buttons to move one page (screen) in either direction. Paging speed

Use the paging speed slider to increase or decrease the paging speed.

Audio

Sensitivity

Use these buttons to change the sensitivity one step at a time.

(Sensitivity can also be changed via the Format Panel or Format Menu). Timebase

These buttons adjust the ‘paper speed’ or timebase.

(The timebase can also be adjusted via the Format Panel or the Format Menu).

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As Recorded

Click this button to quickly change the trace display back to the as-recorded state after reformatting.

Notch

Apply the Notch filter. (also available on the Format Menu).

Frequency

Access the Frequency Graticule tool. Click once on this button, then drag along a trace on the trace display with the Frequency cursor.

The spectral analysis of the selected area is displayed in a graph. The graph can display mutliple selections. Click the Frequency button again to go back to the regular paging cursor.

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Transient Graticule

Access the Transient Graticule tool. Click this button once, then drag on an area on the trace display.

Calculations from the transient graticule are shown beside the measure-ment box. The frequency, duration and amplitude of a waveform are displayed as shown below. Click button again to return to the paging cursor.

Zoom

Click once on the Zoom button, then drag on an area of the trace display to Zoom in for a larger view.

Edit Settings

Click this button to access the Edit Settings dialog. (See the Settings chapter for a description of the various settings available in this dialog).

Panel

Use this button to display or hide the Panel.

Prune

Use this button to toggle the Prune Preview (also available on the File Menu). Choose Save to save the pruned version. See the Settings chapter for a description of the Prune settings dialog.

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Format Bar

This bar is available when Label is deselected on the Toolbars submenu of the View Menu. Quickly switch montages, time base, sensitivity and high and low frequencies. Status Bar The Status Bar appears at the bottom of the Reader window when it is selected in the View Menu.

The Status Bar displays two clocks. The one closer to left shows the time since the last montage change, the other shows the total recording time. Both clocks show time in the following format: date:hour:minutes:seconds.

Overview

Select Overview on the View Menu to display one or more of several overviews available in the Nervus Reader. The Overview submenu is also available as a pop-up menu when you right-click the Overview. Select the overviews you want displayed. The overviews appear across the top of the Reader window, just under the menus and toolbar.

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The Overview allows you to quickly locate interesting parts of the recording. The Overview uses a time scale that is (usually) much larger than the one used in the review pane. Following is a description of the Overview components. Time Scale overview

The Time Scale overview marks the time of the recording and functions as an advanced scrollbar. Drag the thumb markers to scroll to a specific part of the recording.

One of the following two methods of marking the time can be used: Time of day The absolute time when the recording was made. Elapsed time Beginning at 0 when the recording starts and

ignoring delays between segment stop and start.

To choose one of these methods, right-click the overview and select the method you want from the pop-up menu, or choose them on the Overview submenu on the View Menu. Event overview

The Event overview shows a graph with color-coded bars indicating the time of all events. Video overview A horizontal line indicates that video is available for the recorded data. If the cursor is placed over the line, a tooltip appears displaying information about the video segment (start time and duration).

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Zoom overview

The Zoom overview allows you to “zoom in” on just a part of the recording, or view the entire recording in one screen.

Select a time unit (View > Overview > Duration), or choose View Full Scale.

Drag either end of the zoom bar to shorten it and decrease the amount of the recording displayed in the trace display. Click and drag on the middle of the bar to move it right or left to the part of the recording you want to view. While dragging or resizing the Zoom bar, a tooltip appears displaying its position in the recording and its length.

Trends

Trend overview

To display a Trend Overview, select a Trend Template from the list on the Trend submenu of the View Menu. See the Settings chapter for information on creating a new Trend Template.

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Click on a point on the Trend Overview to go to that point in the recording.

Click on the Trend labels and drag to shuffle the placement of the trends around. Move the mouse over a trend to display a tooltip with the actual value of the trend trace, or over the trend label to display the type of trend. Drag the lower edge of each trend to resize.

Right-click a Trend Overview to display a popup menu with two options: Scaling The scaling option allows you to change the minimum

and maximum values of the vertical axis of the trend, which are stored in the current trend template.

Special Choose this to toggle the Special flag on or off. Trends marked as special are not affected by the Trend Panel.

Note: Trend Analysis is an optional feature. Overview options Label Bar Choose Label on the Overview pop-up menu to

show the name of each displayed overview at the left edge of the overview.

Gridlines Choose Gridlines on the Overview pop-up menu to display a grid in the background of the overview.

Vertical Axis Choose Vertical Axis to display a control that can quickly raise or lower the maximum value on the vertical axis for individual trends.

Elapsed Time and Time of Day

Choose one of these options on the Overview pop-up menu to determine how the Time Scale overview is displayed.

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Panel

The Panel appears on the right side of the Reader window when Show is checked on the Panel sub-menu of the View Menu or when the Panel toolbar button is depressed.

Select one or more parts of the Panel on the Panel submenu.

Click on the title bars of the parts of the Panel to expand or contract each part. Click the Arrow button on the left side of the title bar to make a floating palette from each panel. Clicking the arrow again or clicking the close box on the floating palette docks the palette back into the panel. Format Panel The Format Panel is used to quickly select the following formats: Montage: apply a new montage by selecting one from the list. New montages can by added to the list by using the Montage Editor (see the Settings chapter). Timebase: apply a new timebase by selecting one from the list or create a custom timebase by choosing Format Menu > Timebase > Custom. The timebase affects the scrolling speed of the trace display (or change the timebase in steps by clicking on the toolbar buttons). The timebase can be set to display seconds per screen, or millimetres per second. See View Settings, in the Settings chapter. Sensitivity: select a sensitivity setting from the list, or create a custom setting by choosing Format > Sensitivity > Custom (or increase and decrease sensitivity in steps by clicking the toolbar buttons).

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High frequency filter: apply the high frequency filter by selecting a value from the list on the Format Panel or the Format Menu, or select a custom value by choosing Format Menu > High Cut > Custom. Low frequency filter: apply the low frequency filter by selecting a value from the list on the Format Panel or the Format Menu, or select a custom value by choosing Format Menu > Low Cut > Custom. On the Format Menu are also the following: Deflection: select a value from the list or choose Custom to apply a custom value. Notch: click Notch on the Format Menu to apply the notch filter. Special channels You can mark a channel as special by right-clicking on the channel on the live pane trace display and choosing special from the menu. Special channels are not affected when formatting settings are applied. Event list The event list is a tool used for analysing or editing a recording by its events. Following is a list of ways to use the event list: Jump to event: click on any event in the event list and the trace display automatically jumps to that point in the recording. If you scroll to a new page in the recording, the first event on that page is highlighted in the event list.

Sort: the event list can be sorted by event name, time or duration by a simple click on the column header. Click the header a second time to reverse the order.

Delete: to delete events from the list (and the recording) select the event and press the Delete key, or right-click the mouse and choose Delete from the popup menu.

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Print:

Click the Print button to print the currently visible list of events. The printed output includes

l Test ID l Patient Name l Logged on user l Date and time of export Export

Click Export to export the list to a text file (including the above list).

ToolTip: when the mouse is placed over an event for more than one second an tooltip appears. The tooltip displays the abbrevation of the event, annotation, duration, who created the event and when the event was created. Event Filter panel: the Event Filter is used to hide specified events so that they can't be seen in the event list, Overview or the Review Pane. The events filtered are not deleted, so they can be made visible again at any time.

To hide events, the Event Filter uses the properties of the individual events:

Category (checklist with 8 categories): all events of the unchecked categories will be hidden when the filter is applied.

Priority (combobox with High, Normal and Low priority): the events with lower priority than specified in the combobox will be hidden when the filter is applied.

User (combobox – select from a list of users who have inserted events, or select All): all events that are not inserted by the specified user will be hidden when the filter is applied.

Recorded Only

(checkbox): when the Recorded Only checkbox is checked, only events that were inserted when the recording took

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place will be visible when the filter is applied. System Detected Only

(checkbox): when the System Detected Only check box is checked, only detection evetents (Seizure, Spike, Heart Rate) events that were inserted by the automated detections will be visible when the filter is applied.

Spike Sensitivity

(slider): use the slider bar on the Event panel to adjust the level of spike sensitivity.

Use lower spike sensitivity (move the slider to the left) to get rid of false positives and higher sensitivity (move the slider to the right) to be sure as many spikes as possible are picked up.

Note: Spike detection is an optional feature.

Reset (Arrow Toolbar button): stop the filter, i.e. make all events visible.

Video Panel Select Video on the Panel submenu of the View Menu to show synchronous video.

The buttons along the bottom of the panel represent (from left to right): Stop, Play, Step back one frame, Step forward one frame, Zoom in by dragging a selected area and a slider to change the review speed by dragging the slider bar right (to increase speed) or left (to decrease speed).

Drag a lower corner of the window to increase or decrease the window size.

You can scroll to a specific point in the video by dragging the vertical time marker to a point on the trace display. Choose Tools > Vertical Marker to display the marker. When the video is played, the Vertical Marker moves along the trace display in sync. Trends panel The Trends panel is used to switch between Trend Templates and to change the display of the Trend Overview.

Select a Trend Template from the Trend list.

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Duration determines the length of time displayed at one time in the Trend Overview. This is similar to using the Zoom Overview to zoom in on a part of a recording.

Choose a Trend Type from the list.

Choose a minimum and maximum in microvolts.

Note: this panel does not affect Trends marked as special. Montage View panel The Montage View panel shows a quick view of the current montage. Click the Float button (in the left corner of the Montage View title bar) and drag a corner of the window to increase its size and show the numerical positions of each channel.

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Mapping panels Brain Mapping is one of the ways that the Nervus EEG system displays EEG data. In a brain map, each electrode is depicted as a point on a circle representing the head. The value of each point is determined by the EEG data and the mapping method being used. Interpolation is used to gain a value for every point on the circle which is then represented on the screen using color-coded scaling.

Note: mapping is an optional feature. Amplitude Map panel

The Amplitude Map is derived from one data point from each channel.

To choose the point to map, drag the Vertical Marker to a specific point in the.trace display

The Amplitude map can be “played” to show changes in a recording. The Vertical Marker moves along the trace display in synch as the map is played. The buttons at the bottom of the Amplitude Map panel indicate (from left to right): Stop, Play, Step backward, Step forward, and Print.

Note: choose Vertical Marker on the Tools Menu to display the marker.

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Amplitude Map settings Click on the properties button to display a dialog box with these options:

Manual Scaling Choose this to enter custom min/max values. The maximum selected value is mapped to the max color and the minimum value is mapped to the min color.

Note: set the maximum and minimum color using the color-coding tab of the Options dialog. See the Settings chapter for more information.

Automatic Scaling The maximum and minimum values of the whole head are mapped to the min and max color.

Scalp Potential First order difference operator applied to the voltage values.

Surface Current Second order difference operator applied to the voltage values.

Linear Spline Linear interpolation can be described by drawing a straight line between two points. The method used is a two-dimensional analog to this.

Thin Plate Spline Thin Plate interpolation differs from linear in that it provides a smooth surface. This method has been shown to be well suited for evoked potentials.

Note: Spline settings are shared between all maps. Additionally, the color coding is also shared between the maps. See Tools > Options > Color Coding.

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Band Power Map panel

Choose Band Power Map on the View > Panel submenu to display the maps.

The Band Power map is calculated over an interval of time rather than on a time point. All the data on the page currently viewed is used in the calculation. Page to the place in the recording you want to map before displaying the Band Power maps. The power in each electrode over the time period is calculated and divided on the frequency bands, delta, theta, alpha and beta. A Fourier transformation is used in the calculation.

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Click the Properties button to display a dialog box to set the following options:

If Manual scaling is selected, the maximum selected value is mapped to the max color and the minimum value is mapped to the min color.

If Automatic Common scaling is selected, the global maximum and minimum values of the whole head and all the bands are mapped to the min and max colors.

If Automatic Local scaling is selected, the maximum and minimum values of the whole head are mapped to the min and max color for each band individually.

Absolute Normalisation means that no normalisation is made.

Channel relative Normalisation means that each value has been divided by the sum of the values from all electrodes for the same band.

Band relative Normalisation means that the value for each electrode has been divided by the sum of the values from all bands for the electrode.

Linear Spline: same as for Amplitude maps, above.

Thin Plate Spline: same as for Amplitude maps, above.

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Coherence Map panel

Choose Coherence Map on the View > Panel submenu to dis-play the maps.

The Coherence maps are calcul-ated over the time interval of one currently viewed page and are calculated on the frequency bands of delta, theta, alpha and beta. The electrodes in the Coherence maps are analysed in pairs. An electrode pair consists of an electrode and its corres-ponding electrode on the other side of the head, e.g. C4 and C3.

If the power spectrum in a frequency band is similar for the electrodes in a pair, the electrodes are given a value close to 0. If the power spectrum differs, the value will be close to 1

Clicking the properties button in Coherence Maps displays the same dialog as the Band Power Maps discussed above.

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Recorded channels

Choose Recorded Channels on the View Menu to display information about the channels used in the recording and the sampling rates.

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6.5 Protocol

Select a protocol You can apply a whole group of settings, called a protocol, at one time by selecting the desired protocol from the Protocol Menu.

Save a new protocol Save the current configuration of settings by choosing Save on the Protocol Menu. Type in a name for the protocol and click OK. The new protocol appears on the Protocol Menu.

In addition to format settings, the protocol also saves the Event Palette, Trend, Frequency and View Settings. These settings can all be changed via the Edit Settings dialog. (See the Settings chapter for more information).

6.6 Tools Menu

Frequency Graticule This option is also available via toolbar button.

Transient Graticule This option is also available via toolbar button.

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Zoom This option is also available via toolbar button. Vertical Marker The Vertical Marker moves along the trace display during Video or Amplitude map playback. You can drag the marker to a point where you want to view the video or amplitude map. Detections Select a detection template from this list on the Tools Menu. Reports

Create reports Choose Create Report to display a report in html format. Organize reports Organize Reports opens the Organize Reports dialog box. You can use this dialog box to edit and review reports.

6.7 Workspace Menu

Organize Choose Workspace > Organize to open the Workspace folder in a Windows Explorer window if you want to rearrange the folders or shortcuts.

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Create shortcuts on the Workspace Menu to EEG tests of interest for conferences, training etc. Choose Workspace > Add to add a test to any workspace folder. Any number of folders can be created (by clicking the Add Folder button).

Click OK, and the test is added to the Workspace Menu.

6.8 Window Menu

New Window

This feature allows a test to be viewed in multiple windows with different montages. Changes made to events in one view are automatically changed in the other windows.

To open a new window, select New Window on the Window menu.

The test is added to the list at the bottom of the menu and numbered. A checkmark indicates which window is currently active (on top). Switch between active windows by selecting the desired one from this list, or by clicking on any visible portion of the window.

Cascade

Select Cascade on the Windows menu to display the open windows in cascading order, as shown below.

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Tile

Select Tile on the Windows menu to display all of the open windows simultaneously as shown below.

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6.9 Remote Live Review

Select a test currently being recorded (indicated by a red arrow) in the Study Room and click the Review button to review it live in a Reader on the Network.

Make sure Live Pane is selected on the View menu.

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The test can be reviewed in real time, but not edited.

6.10 Keystroke shortcuts

Standard Windows Ctrl+ O - Open Ctrl+ S - Save Ctrl+ P - Print Ctrl+ C - Copy Ctrl+ V - Paste

Other Ctrl+ G - Notch Filter Ctrl+ T - Edit Settings End - Go to End of recording Left Arrow - Step left one second Right Arrow - Step right one second Alt+ Right Arrow - Play Video Forward Page Down - Next Page Page Up - Previous Page Alt+ Page Down - Forward Alt+ Page Up - Backward Space - Stop Forward/Backward Ctrl+ H - Next High cut filter Ctrl+Shift+ H - Previous High cut filter Ctrl+ L -Next Low cut filter Ctrl+Shift+ L - Previous Low cut filter Ctrl+ A - Next Paper speed value

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Ctrl+Shift+ A - Previous Paper speed value Ctrl+ B - Next Sensitivity value Ctrl+Shift+ B - Previous Sensitivity value Ctrl+ W - Toggle Panel Space bar - Stops paging F11 - Toggle full screen Ctrl+Down Arrow - Selects last montage used Ctrl+Shift+V - Toggles floating video window.

Events Events are assigned to the function keys, F3 - F10 and SHIFT+ F2 - F12. This is done in the Event Palette editor according to the order of the event in the Palette.

Montage Montages can be assigned to the keys Ctrl+ 0 - Ctrl+ 9. This is done in the Montage Editor.

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7 Settings

7.1 Customizing Nervus

Customizing Nervus to suit your needs is easy with the Settings Editor and the Protocol feature. Settings are combined into one convenient location accessible by the Edit Settings toolbar button in both the Recorder and the Reader. A group of settings from the Settings Editor, in addition to View preferences, can then be saved to a protocol, which you can access later in one click.

7.2 Recording protocol

The purpose of the protocol is to allow several different configurations, e.g. Routine EEG or Long-Term Monitoring (LTM), and to be able to switch between them with one menu selection. Each protocol is "global", so that if one user changes a protocol, it changes for all.

Selecting and saving protocols The desired protocol is selected from the Protocol Menu in the Recorder and the Reader. A checkmark indicates the active protocol.

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To create a new protocol, choose Save As and give the new protocol a name. The new protocol now appears as the active protocol on the Protocol Menu. Make the desired changes to the Settings Editor (see Settings Editor, following) then choose Save on the Protocol Menu.

To modify a protocol, make sure that it is currently active on the Protocol Menu. Make the desired changes to the Settings Editor, then click Save on the Protocol Menu.

Contents of the protocol: Recorder In the Recorder, the following settings are saved to the Recording Protocol: Amplifier Setup, Sensor Group*, Montage*, Trend Template*, Event Palette, Alert Template, Detection Template, Photic Sequence, Video Template, Views, Frequency Analysis, File Format and Continuous Impedance Test (in Misc Settings), Format** (Format Panel or Format Menu), Panel and Overviews (View Menu).

* See Sensor Groups in the Recorder, below.

** The Notch setting is not saved. Sensor groups in the Recorder The sensor group that is used for recording is not determined directly by the protocol. Instead, each amplifier setup specifies a sensor group to use, and the sensor group specified by the amplifier setup selected by the protocol is the one that is used.

Each montage and trend template specifies a sensor group with which it is to be used. Only those montages and trend templates specifying the current sensor group can be selected.

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As the selection of an amplifier setup thus has a major impact on the protocol, the system never selects amplifier setups without consulting the user. A protocol must therefore always specify a valid amplifier setup. To enforce this all protocols that use a given amplifier setup are automatically deleted when that amplifier setup is deleted. Deleting a sensor group also deletes all amplifier setups that use that sensor group, and thus all protocols that use those amplifier setups.

Contents of the protocol: Reader In the Reader, the following settings are saved to the protocol: Montage, Event Palette, Prune Template, Views, Frequency Analysis, Panel and Overviews (View Menu).

7.3 Settings Editor

The Settings Editor is available in both the Recorder and the Reader. Press the Settings toolbar button, or select Settings on the Protocol Menu to open the dialog.

Click the links at the bottom of the dialog window to display the various editors where you can customize the settings.

Note: the settings available from the Recorder and Reader differ slightly from each other. Additionally, some of the settings described below are optional features and may not appear in the version of the software you are using.

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General instructions Tables in the settings editors are often filled in in a similar way to using Microsoft Excel. The following keys have these functions: Tab key moves across a row in the table. Enter key moves down a column in the table. Arrow keys move in any direction in the table. Right-click deletes or inserts a line (select multiple lines to

delete all at once). Spacebar fills in a checkbox, combo box or field. Or click with the mouse on any field in the table to fill it in.

As you fill in a row of a table, a new blank line is automatically created. Settings Toolbar Many of the settings editors have an editable list of configurations with the following buttons located at the bottom:

From left to right, the buttons indicate: New Create a new configuration. Type in a name for the

configuration, then fill in the required information as needed.

Duplicate Duplicate the selected configuration. Use this if you want to create a new configuration with only slight changes. Give the new configuration a name, then edit only the items you want to change.

Delete Delete the configuration from the list. Rename Highlights the name so you can type in a new one. Move up Moves the selected name up on the list. Move down Moves the selected name down on the list.

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Sensor Editor

With the Sensor Editor, you can create groups of sensors, each con-taining a specified number and type of sensor. The sensor group can then be used to create amplifier setups, montages and trend templates.

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1 Click the New button to create a new sensor group. 2 Type in a name for the group. 3 Tab through the first line of the table on the right (or use the arrow

keys to move around the table), typing in the information or clicking on the space to choose a selection from a drop-down list. As you fill in a line, a new line is added. Keep adding lines as needed.

4 When you are finished, click Save.

To delete a sensor group, select the name from the list and click Delete.

Multiple Sensor Groups

If you want to use 10-10 electrode placement system or use Grid electrodes, check the Enable Multiple Sensor Groups checkbox found in Tools>Options. Then you will be able to select a sensor group in the following dialogs: Sensor Editor, Montage Editor, Amplifier Setup, Trend Editor and Calculated Channels.

Calculated Channels

While montage channels are usually made of one or two sensors depending on whether unipolar or bipolar sensors are used, average and source montages make use of more than two channels to make up a montage channel. The Calculated Channels editor is used to define how these signals are calculated. The Calculated Channels editor is also used when data processing is necessary to calculate a channel based on some other channel. An example of this is when pulse rate is calculated from the EKG. The calculated channels have connections to sensors in the way that a calculated channel must be of a valid sensor type.

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To create a calculated channel, do the following: 1. Click the New button in the Calculated Channels dialog and type in a

name for the channel. 2. Choose a sensor type from the Type list. The following generated sensor types are supported: EEG A combination of many EEG channels can be calculated. The weights are normalized to a sum of 1 when the settings are saved. If a

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channel is not available (not turned on in the Amplifier Setup), it is skipped in the calculation.

Pulse The purpose of this feature is to calculate the heart rate of the patient (in beats per minute) from an EKG signal. The heart rate is calculated during recording and the results are saved to the file as a data channel. The output channel can be treated like any other signal, and can thus be displayed in the trace display or as a trend, and can be used as input for heart rate detection.

Follow the steps below to generate a pulse calculation on the trace display:

1. Create a new Calculated Channel in the Settings Editor by clicking the New icon and typing in a name for the channel.

2. Select Pulse as the sensor type from the Type list. Select an EKG sensor from the Definition list.

3. Select the default color.

4. In the Montage Editor, select the sensor in the Montage, and choose Numerical as the Display Type. The beats per minute are displayed numerically on the trace display.

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Amplifier setup

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Create a new setup To create a new amplifier setup: 1 Click New and type in a name on the Setup list. 2 Select a Sensor Group and a Device from the selectors. 3 Use the arrow keys (or the tab key) to scroll through the channels

and select or type in the desired values. Input: channel label as you want it to appear in the software. On: means data will be acquired for this channel. Sensor: position of the electrode on the head. Sample Rate: Common = the sampling rate selected in the Common

Sampling Rate field. 4 Click Save to save the new setup. Edit setup To edit a setup on the list: 1 Click on the name. 2 Use the arrow keys to scroll through the properties to make the

desired changes. 3 To delete a name from the Setup list, click the name and press Delete. 4 Click the Save button to save the changes. Montage Editor 1 Select a Sensor Group to base the Montage on. 2 Select a Montage from the list, or click New to add a new montage.

While the montage is selected, you can assign a shortcut key by selecting one from the Montage Shortcut Keys list.

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Fill in the information for each montage as follows: Active The Active channel Reference Choose a reference channel from the list. Label Type in the label for the trace, for example, the active

and reference channels separated by a hyphen. This label will appear at the beginning of the trace on the trace display.

Color Select a color for the trace. Display Under Display, choose whether you want the trace to

be displayed graphically as a trace, numerically or both. Choose Off if you don’t want the trace displayed.

Polarity Under Polarity, choose up or down. Special Choose yes under the Special column if you want to

apply characteristics to a channel that remain even when formatting is changed during reviewing a test. Type a value for Sensitivity, Deflection, High cut or Low cut filter. Note: these options are only visible if Yes is selected under Special.

Click Save to save the changes. Montage Sets

The Montage Sets editor is used to create a set of montages. Only montages from the selected set will appear in the montage list box (on the panel in the Recorder and on the toolbar in the Reader). The montages in the selected set are also mapped to the montage buttons on the Recorder toolbar and the keyboard shortcut keys, Ctrl+1 to Ctrl+9.

Creating the set works in the same way as creating an Event palette in the Palette editor.

Click the New button in the Montage Sets editor and type in a name for the set.

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The Montage list on the left contains all of the available montages and the Montages in Set list on the right contains the montages you select to include in the set.

Select a montage from the Montage list on the left to highlight it, then use the right arrow button to add the montage to the Montages in Set list on the right. To remove a montage from the set, select the montage from the Montages in Set list and click the left arrow to move it back to the Montage list on the left.

Use the Up and Down buttons to change the order of the selected montage in either list.

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Photic Editor

Create a photic sequence To create a custom photic sequence for use in the Photic Panel:

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1 Click New and type in a name on the Photic Sequence list. 2 Press Tab, then type in a value for Frequency in the first line. 3 Press Tab again to advance to the Duration and Luminance columns,

then Tab again to advance to the next line in the sequence. 4 Click Save to save the new sequence. Edit a photic sequence To edit a photic sequence. 1 Click a name on the Photic Sequence list. 2 Tab to or click the items you want to change. 3 To delete the sequence, click the name and press Delete. 4 Click the Save button to save the changes made. Trend Editor

Create a new Trend template 1 Click the New button and type in a new name for the template. 2 Select a sensor group from the list. 3 Use the Tab key or the arrow keys to scroll through the columns in

the Settings table. 4 Click Save to save the new configuration. Edit a Trend template 1 Click the name of the configuration on the list to select it. 2 Make the desired changes to the Settings table as described above. 3 Click Delete to delete the configuration from the list. 4 Click Save to save the changes.

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About Trends The following Trends are supported: Total Power, Relative Band Power, Absolute Band Power, Spectrogram, Median Frequency, Peak Frequency, Spectral Edge, Frequency Ratios, Envelope, Generic Trend (data from inputs with low sampling rate, e.g. SaO2 and Heartrate).

The first eight trends are based on spectral computation and are affected by the frequency settings (see the section, Frequency Analysis Editor). The last two trends are time-based.

The frequency-based trends are defined as follows: Total power: the total power is defined as the (normalized) area under the power spectrum "curve". In this case there is a close relationship between the time and frequency domains: let xi denote sample number i and fj the power spectrum estimate at frequency bin j, then Parseval's theorem states that sum(xk

2) = sum(fj). Relative Band power: the power in each frequency band (typically delta, theta, alpha and beta) is computed by summing up the corresponding area under the power spectrum "curve". The total power computation is a special case of band power computations where there is only one frequency band which spans the interval [0, S / 2] where S is the sampling rate. Absolute Band Power: This trend show the power in each of the defined frequency bands (typically delta, theta, alpha and beta). Spectogram: The Spectrogram trend shows the power spectrum of the signal. The power spectrum is represented by using the color-coding specified in the Tools>Options>Color Coding dialog. The vertical axis shows frequency as defined by the bands in the frequency editor. The power can be scaled using the trend scaling tools. The tools are accessed by right-clicking on the trend overview and choosing scaling from the popup menu, or by clicking the vertical axis arrows. Median Frequency: The Median Frequency is the frequency at the point where there is equal power below and above.

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Peak frequency: the peak frequency corresponds to the frequency bin with the largest amplitude. In the example above the peak frequency is close to 0 Hz. Spectral edge: the spectral edge is corresponds to the frequency bin fse, where: sumj = 1... fse(fj) <= a * Ftot fj is the power in bin j, 0 < a < = 1 and Ftot is the total power. In the example above the spectral edge is 14.5 Hz when a = 0.95 (95% spectral edge). The spectral edge parameter, a can be configured via the "Misc" property page available by selecting Tools / Options from the main menu. Frequency ratios: this group of trends shows ratios between power in different frequency bands. The following ratios are provided: alpha : beta alpha : delta (alpha + beta) : delta [the Delta Ratio]

where (for example) alpha : beta is the ratio between power in the alpha band and power in the beta band.

The time-based trends are defined as follows: Envelope: the Envelope trend shows the numerically largest sample from a block of EEG data. Blocks of one second are used so the trend is updated once every second. Generic trend: the generic trend displays (raw) data from the SaO2 and Pulse sensors. The trends are updated once every second.

Note: Trend Analysis is an optional feature.

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Video settings

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Create a new video setup 1 Click New and type in a new name for the setup. 2 Choose No Video, Full Video, or Selective Video.

NB Media File Duration sets the maximum file length in minutes. Selective video Selective video allows you to save video only when certain events occur.

1 Click the events on the Events column to select them, then click the right arrow button to move them to the Selected Events column.

2 Click an event on the Selected Events column to select it. 3 Type in the number of seconds before and after the event you want

the video to be saved to disk. 4 Click Save to save the new video setup. Alert settings Alerts are used to notify the user when special events occur. A set of alerts is selected and saved to an Alert Template that can be saved to the Recording Protocol.

The alert can be an email notification or the start of a specified application. The method of notification can be applied to each event in the alert template separately and the notification can be added to the Application Log.

To create an alert template: 1 Click the New button, or select an existing template and click

duplicate. 2 Move events to and from the Events in Template list by using the

arrow buttons.

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3 Select each event in the Events in Template list and select a method of notification from the Action list.

4 Check Add to Application Log if you want to save the notification to the log.

5 If Run Program is selected as the method of notification, click the Browse button to select the application you want to start.

6 Click Save to save the changes. Event Type Editor Use the Event Type Editor (click Events in the Settings window) to create, edit or delete custom events. New events are added to the configuration database where they are available for use in event palettes. Each event contains user-specified characteristics that aid in locating and sorting placed events. There is also a space to type in a description that can be used for reference. Create an event To create a new event: 1 Click the New icon, and type in a name (8 letters or less) for the

event. 2 Select a color on the Color list. This is the color that will be used

when the event is placed into the recording. 3 Select a category from the Category list. Events can later be sorted

and filtered by category using the Event Filter (see the Event Filter in the Panel section of the Reader chapter for more information on filtering events).

NB Changeable means the position of the event can be changed, or the event can be deleted.

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4 Choose a priority setting from the Priority list. Events can be sorted and filtered by priority using the Event Filter.

5 Check the Duration Event box if the event occurs over a period of time. Duration events are placed into the recording twice, to mark the beginning and end of the event.

6 Type in a description of the event. This is used for reference. 7 Click Save to save the new event. Edit an event To edit an event: 1 Select an event from the list in the Event Editor. 2 While the name is highlighted, change the characteristics as

described in Create an Event, above. 3 Click Save to save the changes. Delete Select an event from the list in the Event Editor and click Delete. Click Save to remove the event permanently from the database.

Note: Nervus comes with 47 pre-defined events. These events can be edited, but not deleted. Event Palette Editor An event palette is a set of events available to the user in a recording session. A palette can contain any number of events from the configur-ation database (see Edit Events, above, to add new events to the database), and individual events can be used in more than one palette.

It is possible to change the size of events in the event palette. Select the size you want from the Event Size list box. (To change the size of events in the trace display, go to Tools>Option and type in a size.)

Use the Event Palette Editor (click Palettes in the Settings window) to create, edit or delete event palettes.

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Create new event palette To create a new event palette: 1 Click the New icon in the Event Palette Editor, and type in a name for

the palette. 2 Select an event from the list of available events. Select multiple

events by holding the Shift or Control keys while selecting. 3 Click the >> button to move the selected events to the Events in

Palette list. Assign shortcuts Shortcut keys are assigned according to the order of the Event in the Palette. The first event has the shortcut key F3, the second F4 until F10, then SHIFT + F2 to SHIFT + F12. If there are more than 19 events in the Palette, these Events have no shortcut key assigned to them.

Edit event palette 1 Highlight the name in the Palettes list. 2 To add new events to the palette, select them from the Event Types

in Palette list, and click the >> button. 3 To remove events from the palette, select them from the Event Types

in Palette list, and click the << button. 4 To change a shortcut key, select the event in the Event Types in

Palette list, highlight the shortcut key field, and type in a new shortcut.

Delete event palette To delete an event palette that is no longer needed, select the name from the Palettes list and click Delete. Save When you have finished creating, editing, or deleting an event palette, click the Save button to save the changes.

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View settings This dialog is used to change the appearance of the trace display of the Live and Review panes. Timebase Choose between millimeters per second or seconds per screen. Page color Click to select a background color from the list, or to create your own custom backround color. Gridlines The first list is to select the number of seconds between each major gridline. The second list is to select the number of minor gridlines between each major gridlines.

Choose a style and color for the major and minor gridlines.

Click Save to save the changes.

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Detection settings Use the Detection Settings dialog to configure which detections you want the recorder to perform during recording.

To create a new Detection template: 1 Click New or Duplicate. 2 Select the detections you want included in the template by checking

the checkboxes on the Detections list. 3 To adjust the settings for each detection type, select the detection

name to highlight it, and fill in the settings in the box on the right side of the dialog. In the above example, the Seizure settings are visible.

4 Click Delete to delete a selected template from the Detections list. 5 Choose a montage from the list, or click Use Display Montage. 6 Click Save to save the changes.

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Seizure detection This detection is used to identify seizures that include sustained paroxysmal rhythmic activity (SPRA) with a fundamental frequency between 3Hz and 20Hz

When a seizure is detected that conforms to the parameters specified in the seizure settings (see diagram above), a duration event is automatic-ally inserted into the recording for the duration of the detection. Spike detection Spike and Sharp Waves (SSW) are detected through a sequential pattern recognition technique. The signal is first broken down into simple sections. A test of these allows for the initial rejection of a large proportion of the data (the rejected sections have a high probability of not containing any epileptic activity). The sections that are kept are tested in a more refined matter and possibly rejected. The analysis proceeds in this fashion, making more and more refined measurements on less and less data. This allows for both fast processing and detailed analysis of meaningful sections.

The Spike detection inserts a Spike event for those traces that form SSW conforming to the parameters specified in the Spike settings. The traces immediately become highlighted.

Note: Spike and Seizure detections are optional features. Heart Rate detection The first channel of type PULSE is used in Heart Rate detection. The pulse rate is based on values (beats per minute) from a sensor of type PULSE (digital heart rate sensor).

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A Bradycardia duration event is opened when the rate drops below the threshold specified in the Heart Rate settings (default 50 bpm) and closed if the rate exceeds that threshold again. The same applies to the Tachycardia event (default 120 bpm).

The range for both Bradycardia and Tachycardia is 1 to 255 bpm.

Frequency Analysis Editor

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Select a Block Duration, a Frequency Resolution, a Detrend setting and a Window Type.

The power spectrum of the data is calculated using Fast Fourier Trans-formation [upper case]. About blocks The EEG is divided into data blocks. Each data block is transformed individually. The overall spectrum is calculated by averaging the spectrum from each block. Large blocks give higher frequency resolution but small blocks give more accurate results. If the Overlap blocks option is selected the blocks overlap by half. This reduces noise in the results. Window type Several window types are supported, including Parzen, Hanning, Hamming, Exact Blackman, and Welch. Definition of frequency bands The default values are shown in the Frequency Analysis Editor dialog. Tab to scroll through the table to change the values.

Click Save to save the new configuration.

Miscellaneous Settings Maximum File Duration

Select a maximum time duration in hours for each separate file. When the time limit is reached, the recording is saved to disk and a new file is started.

File Format Choose the desired file type from the drop-down list.

Continuous Impedance Test

Click the checkbox to continuously check impedance during a recording. (See the section, Continuous Impedance Test in the Recorder chapter for more information about this feature.)

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Prune settings When you have viewed the original recording, you can prune it down to the events and/or the part that you would like to keep.

The selected Prune Template will be the one used when pruning a test with the Prune Preview command on the View Menu or the Prune toolbar button.

To create a new Prune template, do the following: 1 Click New or Duplicate and type in a name for the template. 2 Check Prune Video Only to keep all EEG traces. 3 Select events that you want to keep from the event list on the left

and move them to the list on the right using the right arrow button (remove them again using the left arrow button).

4 Select an event in the right event list to fill in how many seconds before and after the event you want to keep in the pruned recording.

Protocol Editor

The Organize Protocols dialog can now be used to change the protocol settings.

Select the name of the protocol you want to edit from the Protocol list. Then double click each settings category to activate a listbox from which you can select a new setting.

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7.4 Options

Adjust program-wide settings by choosing Tools > Options to open the tabbed Options dialog. Miscellaneous tab Type in a Spectral Edge percentage for Trends. Adjust the Envelope Trend, Duration and Amplitude Profile Level for Envelope Trend as required. Acquisition tab (in the Recorder only) 1 Select a location for the Recording Area. 2 Type in a Default File Name. Screen Size tab Use this tab to adjust your monitor’s horizontal/vertical ratio. Regional tab 1 Select the unit for Sensitivity and Low Cut filter. 2 Choose the Notch Frequency in Hz. Color coding (in the Reader only) Color coding defines the way numerical values are mapped to color. You can choose color schemes as well as the beginning and end colors.

The available color schemes are Rainbow, Heat, Red-Blue and Grayscale. The Steps listbox adjusts the amount of variation between the maximum and minimum colors.

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8 Archiving

EEG and video data can be archived to various storage media, including DVD+RW, CD R/W, and other removable media devices. Contact your distributor for a list of available options.

Note: when you first receive your Nervus system, check the Archive paths and set them as necessary.

8.1 Setting up the Archive paths

All drives being used as Archive devices must be explicitly shared.

Note: the “default share” found in the Disk Properties > Sharing dialog is NOT adequate. Click “New Share” to share the drive.

1 In Nervus Study Room, select Administration Center on the Tools Menu. On the Devices tab, click Add Device.

2 Using the Browse button, look for the appropriate disk drive. Select the drive and click OK. The drive letter will vary depending on the number of drives in the PC.

3 Select the type of media in the Type box. Check the Read and Write boxes and select the Use Media Capacity option.

4 Type a name into the Name box.

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5 Repeat the above process for any other devices (drives) which may be

used for archiving. Remember to include any devices on networked systems.

8.2 Archiving to DVD

Summary There are three steps to the Archiving procedure for DVD. 1 Each time you archive to DVDRAM or DVD+RW, start by formatting

the DVD media. 2 Move the EEG record to the Archive List tab in Study Room. 3 Archive your EEG files directly onto the DVD media.

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Formatting DVDRAM and DVD+RW media You need to do this each time you start using a new DVD disk. 1 Insert a blank DVD+RW into the drive to start the HP DLA software,

or start the software from the Start menu on the taskbar. Click Format, and Next. 3 Type a name for the disk and click Next. The disk will format in 2 to 3

minutes. Note: please note the handling and usage instructions printed on the insert accompanying the HP DVD-RW media.

Archiving EEG Files to DVD 1 Move the EEG files to the Archive List tab in the Study Room. 2 Select a file and click the Archive button. 3 Check Remove Local Copies if you do not want to keep a local copy

of the file. Check Archive Video if you want the video archived (only seen if video has been recorded). Click OK.

4 Select the Device from the list in the Insert Medium dialog. Click OK.

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The Enter Media Name dialog appears. Type in the name that will be used to label the disk, e.g. Disk 001 or November EEGs, and click OK. This is the name that the Study Room will use to track where the EEG files are stored. A message will be shown reminding you to label the disk itself with this name. Subsequent EEGs When subsequent EEGs are selected for archiving, follow the same steps as above. Instead of the Enter Media Name box being shown a message will be displayed asking whether you want to use the inserted medium or not. When the disk is full or there is not sufficient space to store the next EEG file to be archived, a warning message is displayed. Insert a new disk in order to continue archiving. The first time a disk is used, you are prompted for a new media name.

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8.3 Archiving to CD R/W

Summary There are four steps to the Archiving procedure for CD R/W. 1 Move the EEG file to the Archive Tab. Click on Archive to move it

onto the temporary Archive folder. 2 Burn the EEG files to a CD using third-party software. 3 Verfiy that the EEG files are accessible from the CD. 4 Delete the contents of the Archive folder. Archiving EEG Files 1 Move the EEG files to the Archive List tab in the Study Room. 2 Select a file and click the Archive button. 3 Check Remove Local Copies if you do not want to keep a local copy

of the file. 4 If video has been recorded, and you want the video archived, check

Archive Video. Click OK. 5 Select the CD R/W Device from the list on the Insert Medium dialog.

Click OK. 6 In the Enter Media Name, type in the name that will be used to label

the media, e.g. Disk 001 or November EEGs, and click OK. This is the name that the Study Room will use to track where the EEG files are stored. A message will be shown reminding you to label the disk itself with this name.

The EEG file has now been moved to a temporary folder called Archive. When subsequent EEGs are selected for archiving, follow the same steps as above. Instead of the Enter Media Name box being shown a message will be displayed asking whether you want to use the inserted medium or not.

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When the archive folder has reached the limit previously set and there is not sufficient space to store the next EEG file to be archived, a warning message will be displayed. Writing EEG files from the Archive folder to CD To archive these EEG files onto CD media: 1 Run the third-party software provided with the Nervus system. 2 Follow the instructions provided with the software. 3 When the CD burn is complete, check that the EEG files can be opened

from the CD. 4 Empty the Archive folder in preparation for the next set of files to be

archived. To do this, go to Explorer, click the Archive folder on the C drive, and delete the contents but NOT the Archive folder itself.

8.4 Retrieving archived records

The archive process removes the EEG data file (and video if recorded) from the hard disk of the PC thus freeing up storage space. Whilst the patient details are no longer visible within Study Room, they can be accessed at any time using the search functions within study room. If the files need to be viewed, the patient details will provide information as to which media they are contained on. To view the files, put the appropriate media into the PC and click Review.

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9 Web Reader

The optional Web Reader provides a convenient way to find and view EEG tests from a remote location or on a computer that does not have a complete Nervus system installed. The Web Reader runs on a web server and does not require any client installation. If you have purchased this feature, please consult your system administrator for details on how to access the Web Reader.

9.1 Test List

When you first open the Web Reader, the List View is displayed. You can always return to this view by pressing the List View button, shown below.

Test List button

The list view shows the same three tabs that are used in the regular Reader program. The Record List shows tests waiting to be recorded.

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The Review List shows recorded tests that are ready to review. The Archive List shows test ready to be archived.

The currently displayed list can be filtered using the List Filter:

Select a Test Type, Physician and/or Technologist from the listboxes and click the right arrow to filter the list.

9.2 Searching for Tests or Patients

You can search for a specific test or patient by using the Find Test and Find Patient buttons, shown below:

Find Test

Find Patient

The Find Test button opens the following dialog. Fill out any of the information in the form and click the arrow button to display a list of tests with the criteria specified.

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The Find Patient button displays the dialog shown below:

Fill out any of the information and click the arrow button to display a list of tests with the criteria specified.

9.3 Test Properties

Click the Test Properties button for a test in list view to display the Test Properties.

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9.4 EEG Review

Click the EEG Review button to display the EEG trace display of the test. The EEG Review looks and works very similarly to the Nervus Reader.

Data compression is used to reduce the bandwidth requirements. This means faster paging speed when reviewing data over a poor connection.

You can page through a test using the Paging buttons on the toolbar, or step through the test by clicking the trace display or by clicking a point on the overview.

Other available functions on the EEG Review Toolbar include Decrease and Increase Sensitivity, Slower and Faster Timebase, Apply Notch Filter, change Montage and Bandpass filters.

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Index

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10 Specifications

Please note: Taugagreining hf reserve the right to alter specifications.

10.1 M40 amplifier

Inputs 32 monopolar touch-proof inputs 8 bipolar touch-proof inputs

Anti aliasing filters Cut-off frequencies are 33, 67, 134, 268 and 535Hz (± 5%)

Differential input impedance

> 20MΩ

Common mode input impedance

> 100MΩ

Common mode rejection ratio

> 120dB @ 0.16Hz to 70Hz with active patient ground connected

Channel equivalent input noise

< 1.5µV pk-pk @ 0.16Hz to 70Hz

Channel hardware gain

500 (± 4%)

Poly channel hardware gain dc setting

20 (± 4%)

Max. differential ac input before clipping

10mV pk-pk

Max. operational dc input voltage (electrode offset)

± 250mV

EEG channel filter bandwidth

0.16–500Hz (-6dB) (± 10%)

Poly channel filter bandwidth

0.16–500Hz (-6dB) or dc–500Hz (± 10%)

Max. common mode input voltage

2V pk-pk

Input bias current < 5nA Channel cross talk > 40 dB @ 0.16 Hz to 70 Hz

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Digital characteristics Sampling frequency 2048Hz, zero phase on all channels

(simultaneous sample and hold) Sampling resolution 22 bits Sampling quantitisation

0.153µV/bit

Sampling quantisation dc setting

7.8µV/bit

Modes of operation Impedance check < 2, < 5, < 10, < 50kΩ

(pre-defined levels, not continuous) Calibration 10, 20, 50, 100, 150, 500 and 1000µV

square wave Digital post-processing Digital down sampling 128, 256 and 512Hz respectively Digital signal processor

All filtering and display sensitivity scaling carried out in software

Sensitivity 1-2000µV/cm (± 4%), in 13 steps, customizable up to 2000µV/cm

Low filter 0.16Hz–5Hz (± 10%), in 7 steps High filter 15Hz–120Hz (± 5%), in 7 steps) Notch filter 50Hz, 60Hz or off EEG channel, dc filte On or off Montages Montages are completely user-definable

with unlimited number of montage files Safety Standards compliance:

EN60601-1, EN60601-1-1, EN60601-2-26, UL2601-1, EN60601-1-2, CAN/CSA C22.2 No. 601.1-M90

Physical characteristics of amplifier Interface cable 15-wire, shielded, 5m (max 150m) Size 235mm x 150mm x 40mm Weight 730g

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10.2 M24 amplifier

Amplifier inputs 21 monopolar touch-proof inputs 3 bipolar touch-proof inputs



> 20MΩ


> 100MΩ






500 (± 4%)


20 (± 4%)

Max. differential ac input before clipping

10mV pk-pk

Max. operational dc input voltage (electrode offset)

± 250mV


0.16–500Hz (-6dB) (± 10%)


0.16–500Hz (-6dB) or dc–500Hz (± 10%)

Max. common mode input voltage

2V pk-pk

Input bias current < 5nA Channel cross talk > 40 dB @ 0.16 Hz to 70 Hz Digital characteristics Sampling frequency 2048Hz, zero phase on all channels


0.153µV/bit


7.8µV/bit

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Modes of operation Impedance check < 2, < 5, < 10, < 50kΩ

(pre-defined levels, not continuous) Calibration 10, 20, 50, 100, 150, 500 and 1000µV

square wave Digital post-processing Digital down sampling 128, 256 and 512Hz respectively Digital signal processor


Sensitivity 1-2000µV/cm (± 4%), in 13 steps, customizable up to 2000µV/cm

Low filter 0.16Hz–5Hz (± 10%), in 7 steps High filter 15Hz–120Hz (± 5%), in 7 steps) Notch filter 50Hz, 60Hz or off EEG channel, dc filte On or off Montages Montages are completely user-definable



Physical characteristics of amplifier Interface cable 15-wire, shielded, 5m (max 150m) Size 235mm x 150mm x 40mm Weight 730g

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201

10.3 C32 amplifier

Amplifier inputs 32 referential or up to 16/32 bipolar touch- proof inputs (configurable in the software) plus 4 additional DC inputs



> 20MΩ


> 100MΩ






500 (± 4%)


19.5 (± 4%)

Max differential ac input before clipping

10mV pk-pk

Max operational dc input voltage (electrode offset)

± 250mV


0.16–500Hz (-6dB) (± 10%)


0.16–500Hz (-6dB) or dc–500Hz (± 10%)

Max common mode input voltage

2V pk-pk

Input bias current < 5nA Channel cross talk > 40dB @ 0.16Hz to 70Hz

Digital characteristics Sampling frequency Up to 2048Hz, zero phase on all channels

(simultaneous sample and hold) Sampling resolution 22 bits Sampling quantisation: ac setting

0.153µV/bit

Modes of operation

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Impedance check < 2, < 5, < 10, < 50kΩ (pre-defined levels) or continuous impedance checking

Calibration N/A Digital post-processing Digital down sampling 128, 256, 512 and 1024Hz respectively Digital signal processor


Sensitivity 1-2000µV/cm (± 4%), in 13 steps Low filter 0.16Hz–5Hz (± 10%), in 7 steps, or user-

configurable High filter 15Hz–120 Hz (± 5%), in 7 steps, or user-

configurable Notch filter 50Hz, 60Hz or off Montages Montages are completely user-definable

with unlimited number of montage files Physical characteristics of amplifier Interface cable 5, 10 or 20 metres Size 115 x 75 x 45mm, plus 115 x 50 x 45mm for

the electrode connection block Weight 385 g approx.

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203

10.4 C64 amplifier

Amplifier inputs 64 referential or up to 32/64 bipolar touch- proof inputs (configurable in the software) plus 4 additional DC inputs



> 20MΩ


> 100MΩ






500 (± 4%)


19.5 (± 4%)


10mV pk-pk


± 250mV


0.16–500Hz (-6dB) (± 10%)


0.16–500Hz (-6dB) or dc–500Hz (± 10%)


2V pk-pk

Input bias current < 5nA Channel cross talk > 40dB @ 0.16Hz to 70Hz

Digital characteristics Sampling frequency Up to 2048Hz, zero phase on all channels

(simultaneous sample and hold) Sampling resolution 22 bits Sampling quantisation: ac setting

0.153µV/bit

Modes of operation

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Impedance check < 2, < 5, < 10, < 50kΩ (pre-defined levels) or continuous impedance checking

Calibration N/A Digital post-processing Digital down sampling 128, 256, 512 and 1024Hz respectively Digital signal processor


Sensitivity 1-2000µV/cm (± 4%), in 13 steps Low filter 0.16Hz–5Hz (± 10%), in 7 steps, or user-

configurable High filter 15Hz–120 Hz (± 5%), in 7 steps, or user-

configurable Notch filter 50Hz, 60Hz or off Montages Montages are completely user-definable

with unlimited number of montage files Physical characteristics of amplifier Interface cable 5, 10 or 20 metres Size 115 x 75 x 45mm, plus 115 x 50 x 45mm for

the electrode connection block Weight 385 g approx.

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10.5 U32 amplifier

Amplifier inputs 32 referential or up to 16 bipolar touch- proof inputs (configurable in software)



> 20MΩ


> 100MΩ


>110dB @ 0.16Hz to 70Hz with active patient ground connected




500 (± 4%)


19.5 (± 4%)


10mV pk-pk


± 250mV


0.16Hz–500Hz (-6dB) (± 10%)


0.16Hz–500Hz (-6dB) or dc–500Hz (± 10%)


2V pk-pk

Input bias current < 5nA Channel cross talk > 40dB @ 0.16Hz to 70Hz Digital characteristics Sampling frequency 2048Hz, zero phase on all channels


0.153µV/bit


7.8µV/bit

Modes of operation Impedance check < 2, < 5, < 10, < 50kΩ (pre-defined levels)

or continuous impedance checking Calibration N/A

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Digital post-processing Digital down sampling 128, 256, 512 and 1024Hz respectively Digital signal processor


Sensitivity 1-2000µV/cm (± 4%), in 13 steps Low filter 0.16Hz–5Hz (± 10%), in 7 steps High filter 15Hz–120Hz (± 5%), in 7 steps) Notch filter 50Hz, 60Hz or off Montages Montages are completely user definable



Physical characteristics of U32 amplifier Interface cable 5 metres Size 238mm x 155mm x 45mm Weight 670g

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10.6 Photic stimulator

Flash rate User-definable from 1–60Hz (± 1%) Flash energy 0.125J–1.0J (± 10%), in 8 steps Mains input 230/115V~ 50Hz/60Hz 50VA Standards compliance EN60601-1, UL2601-1, EN60601-1-2,

CAN/CSA22.2 No 601.1 Size 235mm x 150mm x 40mm Weight 770g

10.7 ISO1000 isolation transformer

Input 100-120V/200-240V~ (user adjustable in mains inlet module, factory set to 200-240V)

Output 1000VA for 110-120V/200-240V~ ( 900VA for 100V~ )

Fuses (F1/F2) T10A H 250V for 100-120V and T6.3A H 250V for 200-240V

Size 310mm x 220mm x 115mm Weight 12.5kg

10.8 Medical power supply for Notebook, U32, IBox

Input 100-240VAC (-10%, +10%), 47 – 63 Hz Output Auto sensing 15v dc output Size 129mm x 77mm x 40mm Weight 370g

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Index

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Acquiring data. See Data acquisition

Acquiring video. See Video acquisition

Administrative options, 90 After-sales service support, 22 Alert settings, 174 Amplifier setup, 165 Amplitude Map panel, 142 Analysis. See Detection Anti-virus software, 15 Archive button, 68 Archive List, 65 Archive paths, 185 Archiving, 185

Retrieving archived records, 190 To CD R/W, 189 To DVD, 186

Artefact, 26 As Recorded button, 131 Band Power Map panel, 144 Brain Mapping, 142 Browsing a recording, 58 Cables, 36 Cautions and warnings, 6 Channels not affected by

formatting, 138 Cleaning, 23 Closing a test, 58 Coherence Map panel, 146 Color coding numerical values, 184 Command buttons, 66 Connecting the equipment, 27 Connection diagrams, 39

24 channel desktop, 41 24 channel notebook, 45 32 channel USB notebook, 43 32/64/128 channel LTM desktop,

42 40 channel desktop, 40 40 channel notebook, 44 Adding printer for notebook, 46

Connections C64 compact amplifier, 32

Connection symbols, 48 M40 amplifier, 31, 34 Main power (Desktop systems),

27 Main power (Notebook systems),

29 Medical Power Supply PSU001, 30 Nervus IBox, 30 Photic stimulator, 35 Standard PC equipment, 36 U32 amplifier, 33 USBIFB/01 interface card, 30

copy protection key, 36 Customizing Nervus, 157 Data acquisition, 112 Data blocks, 182 Databases, external, 85 Deflection setting for all channels,

104 Detection, 91

Heart Rate, 180 Seizure, 180 Spike, 180 Window type, 182

Detection settings, 179 Dongle. See Copy protection key Duration events, 118, 127 Edit Settings button, 132 Editing a recording, 60 Electrical interference, 24 Environmental parameters for

operation, 9 Environmental variables, 85 Event filter, 139 Event List, 106, 138 Event markers

In Reader, 59 In Recorder, 57

Event Palette, 176 Event palettes, 98 Event Type Editor, 175 Events, 117, 120

Automatic, 120 Duration, 118, 127

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Hiding. See Event Filter Marking, 117, 127

Events, Reader window, 126 Existing Patient, 70 External databases, 85 External pin connections

Ibox, 50 U32 amplifier, 50 USBIFB/01 interface card, 50

File duration Maximum, 182

File Menu, 68 Filter

High frequency, 138 Low frequency, 138

Filters Channels not affected, 104

Find Patients command, 79 Find Tests command, 76 Format Bar, 133 Format Panel, 137 Frequency Analysis

Default frequency bands, 182 Editor, 181

Frequency Graticule, 131 Fuses, 23 Heart Rate detection. See

Detection: Heart Rate Hiding specified events, 139 High frequency filter, 104, 138 Hyperventilation panel, 105 Impedance test, 55, 112

Continuous, 114 Installation, 8 Keyboard shortcuts, Reader

window, 126 Live Event Palette, 98 Live Pane, 97 Logging off, 75 Low frequency filter, 104 Low frequency filter:, 138 Mains power connections, 10 Maintenance, 22, 23 Mapping panels, 142

Marking duration events, 118 Marking events, 127 Marking Events, 117 Montage, 103, 137

Editing, 166 Montage View panel, 108, 141 Move Left and Move Right buttons,

66 Nervus database, 81 Nervus Reader, 58, See Reader Nervus Recorder, 55, 95 Nervus system

Concepts and terminology, 14 Connections, 27 Disposal of equipment, 7 Handling, 4 Key features, 12 Product variants, 16 Responsibility of manufacturer, 7 Staff qualifications, 4 System components, 4 Transporting the system, 20 User Administration, 80

Networking, 93 New Patient, 69 Notch filter, 131 Open Test command, 71 Opening a recording, 58 Overview

Event, 110, 134 Options, 136 Time Scale, 110, 134 Trend, 111, 135 Video, 110, 134 Zoom, 110, 135

Overview, Reader window, 133 Overview, Recorder window, 109 Paging buttons, 130 Paging buttons, Reader window,

125 Paging speed, 130 Panel

Format panel, 103 Recorder window, 102

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Show or hide, 132 Panel, Reader window, 137 Paper speed. See Timebase, See

Timebase Parameters

Changing, 59 Patient properties, reader window,

126 Patient registration, 53 Photic

Editing, 170 Photic panel, 105 Power supply connections, 10 Protocol, 116, 148

Reader, 159 Recording, 157 Saving a new, 116, 148 Selecting, 116, 148

Prune settings, 183 Prune template

Create a new, 183 Pruning a recording, 60, 88 Reaction time stimulator, 107 Reader, 123 Reader window, 124 Reassign a patient to a test, 90 Record button, 67 Record List, 64 Recorded channels, 147 Recorder window, 96 Recording in Calibration Mode, 116 Recording parameters, 56 Recording protocol. See Protocol:

Recording Refresh button, 68 Registering a patient, 53 Registering files in the Nervus

database, 81 Reporting, 60 Review button, 67 Review Event Palette, 98 Review List, 65 Review Pane, 97 Safety standards, 5

Sampling rates for recorded channels, 147

Searching for a patient, 79 Searching for a test, 76 Seizure detection. See Detection:

Seizure Selecting more than one test, 66 Selective video, 115 Sensitivity, 137 Sensitivity buttons, 130 Sensitivity setting for all channels,

104 Sensor Editor, 161 Sensor group, 162 Settings, 157 Settings Editor, 159 Settings Toolbar, 160 Setup

Alerts, 174 Amplifiers, 165 Appearance of trace display, 178 Detection, 179 Event Types, 175 Montages, 166 Photic, 170 Protocols, 157 Sensors, 161 Video, 173, 174

Showing synchronous video, 140 Special channels, 104, 138 Special instructions for use, 20 Specifications, 191, 197

C32 amplifier, 201 C64 amplifier, 203 ISO1000 Isolation transformer,

207 M40 amplifier, 197 Medical power supply, 207 Photic stimulator, 207 U32 amplifier, 205 M24 amplifier, 199

Spike detection. See Detection: Spike

Start recording, 56, 114

Index

213

Status Bar recorder window, 100

Status Bar, Reader window, 133 Stop recording, 57 Study Room, 53, 63 Study Types, 83 Switching OFF, 38 Switching on, 37 Symbols and their definitions, 47 Test Information, 70 Test Menu, 86 Test properties, Reader window,

126 Timebase, 103, 130, 137 Toolbar

Recorder window, 99 Toolbar, Reader window, 129 Tools Menu, 76 Tools Menu, Reader window, 148 Trace display, 97 Transient Graticule, 132 Trend template

Editing, 170 Trends, 135, 171

Band power, 171 Envelope, 172 Frequency ratios, 172 Generic trend, 172 Peak frequency, 172 Spectral edge, 172 Total power, 171

Trends panel, 141 Trends, switching between, 107 User Administration, 80 Version information, 85 Video

Selective, 115 Video acquisition, 115 Video Capture panel, 108 Video Panel, 140 Video settings, 173 View Menu, 76 View Menu, Reader window, 129 View Menu, recorder window, 99

View Referral button, 67 View Report button, 67 View settings, 178 Viewing a referral, 88 Viewing a report, 88 Viewing a test, 88 Viewing live traces, 112 Warranty, 2 Work Area, 82 Workspace Menu, 92, 149, 150 Zooming, Reader window, 132

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What’s New in Nervus EEG Version 3.3?

New in the Recorder

Stop Watch

The Stopwatch is a new panel item intended to help EEG technicians perform tasks that require precise timing. A duration event is inserted to mark the use of the Stopwatch in the recording and includes an annotation and the time duration. To use, type the annotation in the space provided, or select a previously typed annotation from the drop down list. Click the arrow button to start the timing. Click the arrow button a second time to stop the timing. The time is displayed on the panel to the nearest 10th of a second.

Burst Suppression The new Burst Suppression features eliminate the need to manually count bursts. Three types of burst channels, the Burst Suppression Ratio, the Burst Rate and the Inter Burst Interval, have been added to the Calculated Channels editor. These channels can be displayed on the Alert Strip (see the Alert Strip section, above) to display real time burst count. Or, the channels can be displayed as Trends, to allow burst suppression management of the entire recording. To display the burst channel as a Trend, create a new trend in the Trend Editor and select Generic as the type. Then select the burst channel from the list.

Use the Calculated Channels editor to create a new burst channel or modify an existing one. Create a new channel on the Calculated Channels list and select one of the three Burst types from the Type selection box. Choose Active and Reference channels from the Definition section and a Default color for the channel if desired.

The Burst Suppression Ratio is defined as the percentage of time the signal from the channel is in a suppression state in a one minute block length. The Burst Rate is defined as the number of bursts within a one minute block length.

The Inter Burst Interval is defined as the length in seconds of the last suppression period.

New Trend – Alpha Variability The alpha variability trend is a measure of relative alpha power. It shows power in the 6 - 14 Hz band expressed as a percentage of 1 - 20 Hz activity. Frequency analysis is performed on 2 second epochs averaged over 2 minutes.

The alpha variability trend can be useful in early detection of vasospasm.

Sound Alerts A new action, “Play Sound”, has been added to the Action list in the Alert Settings dialog. Select the event you want to assign the action to from the Event Types in Protocol list. Select Play Sound from the Action list. Click the Browse button to browse for a .wav file to play when the event occurs.

Overview Lock Recent Choose View>Overview>Lock Recent, or right-click on the overview and select Lock Recent from the popup menu. This locks the overview into always showing the most recent duration. The duration is selected on the View>Overview submenu or the Overview popup menu.

Reader

Link Segments in Export When exporting recordings to EDF format, you can now link recording segments to create one file. A “zero” signal (straight line) is inserted for the duration of the segment break. Choose File>Export to open the Export dialog. Select “Whole File” and check Link Segments. Note that a single current montage must be selected to export to EDF format. Usually, this means something other than “As Recorded” must be selected.

Print Trends

Use the Print Trends command on the File menu to print all or part of the Trends. Choose the duration you want to print on the View>Overview submenu, or by right-clicking on the overview and selecting a duration from the popup menu. Slide the zoom bar to the desired location.

Choose Print Preview Trends to show how many pages the printing will require. To reduce the number of pages, choose a longer duration. Choose Page Setup Trends to set the page size and access your printer setup.

Copy Trends to clipboard Choose Edit>Copy Trends to copy the (currently displayed?) trends to the clipboard. You can then paste the image into an image editor, such as Microsoft Paint and the image can be attached to a patient’s folder.

Study Room

Double click test to open Recorder or Reader Double click on a test in the Study Room to open the test in the Recorder, or the Reader if the test is on the Review list. Previously, double clicking opened the test properties. The test properties can be accessed by clicking the Properties button, choosing File>Test Properties, or by right clicking the test and choosing Test Properties from the popup menu.

Other New Features

Ongoing Alerts A simple, stand alone application keeps a running list of active alerts on all tests currently being recording on the network. For each test, the following information is displayed: Bed ID, Test ID and Patient Name. This text functions as a hyperlink to open the test in the Reader when clicked. Under the hyperlink is displayed the Alert, an Annotation and the time of onset. This application can be used in the Doctor’s office to give quick access to tests in progress and to monitor alerts. Alternatively, department engineers could use the application to discover full hard drives, faulty amplifiers, etc.

Remontage added to EEG viewer (formerly the Browser)

It is now possible to remontage in the EEG viewer using any montages defined in the acquisition system at recording time.

What’s New in Version 3.4?

Sleep Analysis

Introduction Nervus 3.4 is a full featured sleep analysis program including manual and automatic sleep staging, a range of automatic analyses, reports and calibration of external devices such as oximeters and CPAPs.

Sleep Scoring The software is equipped to handle both manual sleep scoring as well as automatic R&K. A test can be scored while recording in real time, or in the Review pane. The test can also be scored multiple times in the Nervus Reader. Several sleep scores can then be displayed simultaneously in a hypnogram overview in the Nervus Reader.

Sleep Settings The Sleep Settings are found in the Miscellaneous Settings page of the Settings Editor.

Sleep Mode To enable the sleep scoring features, the Recorder must be in Sleep Mode. Check the Sleep Study option to activate sleep mode.

Adult or Infant Sleep Stages Also in the Sleep Settings, you can also select whether to use Adult or Infant sleep stages. This will change the appearance of the Sleep Staging panel. The difference is indicated below:

Adult: W (Awake), M (Movement), R (REM), 1 (Stage 1), 2 (Stage 2), 3 (Stage 3), 4 (Stage 4), ? (Unsure) Infant: W (Awake), M (Movement), AS1 (Active after wakefulness), AS2 (Active after quiet sleep), I (Indeterminate), Q (Quiet), ? (Unsure) After making changes to the Sleep Settings, press save to save the changes to the Protocol.

Convert to Sleep If the test was not in Sleep Mode during recording, the test can still be scored in the Reader by choosing File>Convert to Sleep.

Note: The Sleep Option is required to be able to Convert to Sleep.

Manual Scoring in the Recorder To score the test manually in the Recorder, display the Sleep Staging panel (View>Panel>Sleep Staging). Choose “Manual” from the Sleep Score list to score the test completely manually, or “Automatic” to correct the automatic scoring. Press the appropriate sleep stage button to insert the sleep stage into the recording. Use the pound symbol button to hide/show the sleep stage watermark in the Review pane (or Reader window). The lock button is used to lock the display to a single 30 second epoch. Use the mouse or Page Up/Page Down to scroll the Review pane (or Reader window) to the next or previous sleep stage.

Adult Sleep Stage Panel

Infant Sleep Stage Panel

Shorcut Keys You can also use the number keypad on the keyboard to insert sleep stages. Following are the shortcut keys for the adult and infant sleep stages: Adults: 0 = W, 1 = 1, 2 = 2, 3 = 3, 4 = 4, 5 = R, 6 = M, 9 = ? Infants: 0 = W, 6 = M, 1 = AS1, 2 = AS2, 3 = I, 4 = Q, 9 = ?

Manual Scoring in the Reader In the Nervus Reader, the test can be manually scored multiple times. To create a new sleep score, open the Sleep Score Manager panel (View>Panel>Sleep Score Manager or right click the Panel and choose Sleep Score Manager from the list). Click the “new” icon (bottom left) and type a name for the sleep score. Then score the test as described above using the Sleep Staging panel or the corresponding shortcut keys. If the test was scored manually in the Recorder, the manual sleep score will be named “manual” when the test is opened in the Reader.

Automatic Sleep Staging When Automatic sleep staging analysis is activated, a sleep stage is automatically assigned to every 30 second epoch. For each epoch, the algorithm estimates the probability of belonging to each stage. The most probable stage is assigned to the epoch unless the corresponding probability is below a specified threshold. In that case the sleep stage from the previous epoch is used. This functionality is available both online in the Recorder and to be performed afterwards in the Reader. Automatic sleep staging is not available for Infant sleep stages.

Activating Automatic Sleep Staging in Recorder Protocol To perform automatic sleep staging during acquisition the “Sleep Staging” detection must be enabled in the recording Protocol. To activate automatic sleep staging in the Protocol, select “Sleep Staging” in the Detections Editor, set the parameters and press save to save the changes to the detection template. Save to the Protocol by pressing Save on the Protocol menu.

Activating Automatic Sleep Staging in Reader To perform automatic sleep staging select a detection template that has “Sleep Staging” enabled from “Tools, Detections” menu.

Automatic Sleep Staging Settings

The following parameters are required in the Sleep Staging Settings area:

Model File: Browse to the file containing classification information. There are some model files supplied with the system, but it is also possible to create your own files. Use Default Channels: If checked, the channels specified when the model file was created are used for sleep staging. EEG Channel: Select Active and Reference channels. Threshold: Enter a value between 0 and 99%. Suggested values are between 50% and 70%. The threshold is the minimum probability to change a sleep stage. A high value makes the algorithm reluctant to change sleep stage.

Adaptable R&K Model The automatic sleep staging algorithm uses an advanced pattern recognition algorithm to classify epochs. The algorithm has been "trained" on several sleep recordings which have been scored by experts and the results are stored in the default model file. It is possible train the algorithm to your own specific needs. To do so, follow these steps: 1. Open the Sleep Staging trainer program (SleepStagingTrainer.exe) 2. Press New and enter a name for the new model file (e.g. "MyStaging") 3. Add 5 - 10 sleep files that have been scored according to your requirements. Make sure they all have a score named "Training". (If not, you can copy an existing score in the Sleep Score Manager panel in the Reader and name it "Training") 4. Select the channels to be used (e.g. C3-A2). Make sure they exist in all the recordings. 5. Press the Train button. The training process takes a while. When finished, close the training program. A new model file (MyStaging) is now available in the Detection Editor.

Automatic Detections Parameters for the automatic analyses described in the following section can be defined in the Detections Settings editor. Event Markers are automatically inserted into the trace display when one of the events occur.

The above graphic shows the available detections in the Detections Settings editor (Click the Edit Settings toolbar button and click Detections). The checkmarks indicate which detections will be active in the currently selected detections template. Highlight the selection by clicking the name to display and configure the individual settings for each detection type.

Apnea/Hypopnea Nervus automatically inserts apnea and hypopnea events based on parameters that you define in the Detections Settings editor. If a respiratory effort sensor is used, the apnea/hypopnea is further classified as obstructive, central or mixed.

Note: The respiratory effort signal must have the same sampling rate as the airflow signal.

Minimum Duration: The minimum duration in seconds of the apnea/hypopnea to trigger an event. Valid range is 1-120 seconds. Apnea Threshold: The minimum percent of background amplitude that triggers an apnea event. Valid range is 1-98%. Hypopnea Threshold: The minimum percent of background amplitude that trigger a hyponea event. It must be larger than the apnea threshold and less than or equal to 99%. Airflow Channel: Select the sensor used to record the airflow signal. Respiratory Effort: Check the checkbox if respiratory effort is being recorded and select the relevant sensor used to record the respiratory effort signal. SaO2 Association: Check the checkbox to mark apnea events only when desaturation occurs. Specify the valid time limit in seconds in which the desaturation should occur after the apnea begins. Specify the valid percentage of desaturation necessary to record the apnea.

Desaturation Nervus detects desaturation from a SaO2 channel and inserts an event marker into the trace display (and into the Sleep Event Overview) for the duration of the desaturation. The following graphic shows the default parameters in the Detection Settings editor. These values can be adjusted by typing in a new value in the spaces provided.

Heart Rate Bradycardia and Tachycardia events are detected from a Pulse sensor type obtained from a pulse oximeter or by calibrating a pulse sensor from an EKG signal. The Arrhythmia event uses a type R-R interval sensor. A duration event is automatically inserted for the duration of these events. The following chart shows the default thresholds and the valid range for each event type: Heart Rate Event Default Threshold Valid Range Bradycardia 50 bpm 1-255 bpm * Tachycardia 120 bpm 1-255 bpm * Arrhythmia 30% 0-100%

*The value for bradycardia must be lower than the value for tachycardia. The following graphic shows the Heart Rate settings in the Detection Settings editor.

This means that a Bradycardia event is inserted if the heart rate goes below 50 bpm and a Tachycardia event is inserted when the heart rate goes above120 bpm. Arrhythmia is detected when there is a sudden change in the R-R interval. If the Arrhythmia threshold is 30%, the event is inserted if an R-R interval is 30% shorter or longer than the median of the previous three intervals.

PLM Periodic Limb Movements are detected by a signal from a PLM sensor attached to the patient. A duration event is inserted for the duration of the detected movement. The default criteria are shown in the following graphic from the Detection Settings editor.

The signal is filtered using specially designed filters. Baseline amplitude is calculated using moving average. The algorithm waits for the amplitude to rise 3 times the value of the baseline amplitude for at least 0.5 seconds and a maximum of 5 seconds. For a PLM to be marked, this must happen at least 4 times for at least 4 seconds, but no more than 90 seconds between bursts. In this case all the detected bursts are marked with a PLM event.

Body Position The Nervus system supports DC body position sensors. These sensors give a different output voltage for different body positions. When body position is changed, one of the following events is inserted: Prone, Supine, Left Right and Upright. Some body position sensors give greater output than the dynamic range of the Nervus amplifier. In this case, use the R1 input on the side of the amplifier which scales down the signal.

Body Position Settings The voltages for the body positions and the minimum duration for each position are user definable in the Detections Settings editor. The upper

and lower limits (the midline between voltages) are then calculated for each position. The following graphic shows the default values.

It is necessary to measure these values for each body position sensor. To do so, follow these steps: 1. Connect the sensor to the input you plan to use on the amplifier. 2. Enable the body position sensor in the Amplifier Setup on the input you plan to use. 3. Create a montage that includes the body position sensor and displays the values numerically. 4. Now, turn the sensor to each side and write the output voltage in the Body Position Settings window as appropriate.

Manual Body Position Events Body position events can also be inserted manually using the body position event markers.

MSLT The MSLT panel (View>Panel>MSLT) is provided to assist Multiple Sleep Latency tests. It helps keep track of the time from Lights Off to Sleep Onset and from Sleep Onset to when the patient is woken up again.

Click the light bulb icon to insert the Lights Off event and start the top timer. Click the “ZZZ” icon to insert a Sleep Onset event and start the bottom timer. The reset button resets both clocks, making the system ready for the next nap. The Lights Off event and the Sleep Onset event can be manually moved afterwards in the Review pane or in the Reader application to ensure accurate results in the report.

Sleep Overviews Nervus has several clickable overviews to graphically display the progress of sleep analysis over the entire recording or a selected duration. Following is a list of the available overviews:

Hypnogram Sleep Events SaO2 Heart Rate CPAP Body Position

These overviews work like other overviews in Nervus. To summarize: To display the overviews, choose View>Overview and select the desired overviews from the list, or right-click the overview and select from the popup menu. Click anywhere on the overviews to display that area of the trace display in the Reader or the Review Pane of the Recorder. To change the duration of the overview, right-click the overview and select a value from the Duration sub-menu. As with other overviews in the Recorder and Reader, the sleep overviews can be resized by dragging the upper and lower edges. Following is more detailed information about each overview.

Hypnogram The sleep hypnogram is a graphic representation of the sleep stages.

In the Reader, if the test has been scored more than once, use the Sleep Score Manager panel to select the hypnogram you want to display.

Check “Compare Hypnograms” to display all hypnograms simultaneously.

Change the order of the displayed hypnograms by dragging the label area up or down.

Sleep Event Overview The Sleep Event overview shows tic marks for Apnea, Hypopnea, Desaturation,

Heart Rate, PLM and Arousal events. The marks are easy to click on to display the corresponding traces.

SaO2, Heart Rate and CPAP Oxygen Saturation, Heart Rate and CPAP can be displayed in the Reader as trace overviews, making it easy to see the progress over the whole recording or a selected duration.

The following table shows the default upper and lower bounds for each overview type, but these values can be changed by right-clicking on the overview and choosing Trends>Scaling. Overview Unit Lower Upper SaO2 % 80 100 Heart Rate bpm 40 120 CPAP cmH2O 0 20

Body Position Overview The Body Position overview gives a quick visual picture of body position changes.

The body postition events can be inserted manually or automatically, based on the parameters set in the Detections Settings editor (see the above section on automatic detections). The overview is generated from these events.

Sleep Reports Nervus generates three types of sleep reports, Polysomnography, Multiple Sleep Latency Test and a Sleep Referral report.

The sleep report is generated from the Nervus Reader by selecting the report type from the Tools>Create Report submenu. The report is automatically displayed in a separate Report Editor application. The report can be edited, saved to the patient’s document folder or printed using standard file and edit menu items, or by pressing the toolbar buttons for these commands. Choose Tools>Organize Reports to view, edit, rename or delete reports.

Sleep Report Events There are two new event markers, Start PSG and Stop PSG that can be inserted into the recording to deliniate the duration of the Polysomnography and Sleep Referral reports.

Polysomnography Report The Polysomnography report provides the following summaries: Patient/Test Information Hypnogram Sleep Summary

Sleep Stages Conclusion (an editable area to be filled in after report generation) Sleep Cycles Heart Rate Summary Bradicardia/Trachycardia/Arrythmia Heart Rate – Sleep Stage Respiratory Summary Respiratory – Sleep Stage Respiratory – Body Position Arousals SaO2 Summary SaO2 Statistics CPAP Sleep Overview (image)

Multiple Sleep Latency Report The MSLT report provides the following summaries: Patient/Test Information Number of Naps Min, max and mean Sleep Latency Min, max and mean REM Latency For every nap: Sleep Latency REM Latency REM duration Number of REM episodes

Sleep Referral The Polysomnography report provides the following summaries: Patient/Test Information Hypnogram Sleep Summary Sleep Stages Conclusion (an editable area to be filled in after report generation)

DC Sensor Calibration In many cases the value of interest from the analog input is not the voltage. An example is oxygen saturation where the saturation is in percentages. To convert the voltage into the desired unit, it is necessary to provide the system with some information. This can be done manually by providing the “Conversion factor” and “Offset” that satisfy the formula:

Value = Conversion factor x voltage + Offset Where the voltage is in milli volts. Example: An oximeter gives out 1000 mV for 100% and 0 mV for 80%. Then the conversion factor should be 0,02 and the offset 80%. 90% = 0,02%/mV x 500 mV + 80% This can also been done in a semi-automatic way. Then the Conversion factor and offset are calculated by the program based on measurements. To calibrate a device, follow these steps:

1. Connect the device to one of the analog inputs on the interface board or a poly input on the amplifier.

2. Open the Sensor Editor and create a new sensor or select an existing one.

3. Click the Calibrate button 4. Select the appropriate input from the drop down list. 5. Check the Assume Zero Offset box if it is expected that 0 volts

equals 0 units. 6. Configure the device for a high value output. 7. Press the Read button (under the High field) to input the

voltage value into Nervus. 8. Enter into the High field the equivalent unit value for the

device, e.g., the number of BPM for a heart rate device. 9. Repeat steps 6-8 for a low value if relevant (see step 5). 10. Click the Update button. 11. Click the Save button at the bottom of the Sensor Editor to

save the new sensor with its calibrated settings.