physicain training slidesmay 25-3 final nov 7 2012.ppt

STAR S4 IR Excimer Laser System Physician Certification Course

Place for Conference or AuthorMonth Day, 200X

2012.03.13-ST4862

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Purpose

The purpose of this presentation is to certify physicians to use the STAR S4 IR Excimer Laser System

In addition to completing this course, it is the responsibility of physicians to read and understand the

• STAR S4 IR Excimer Laser System Operator’s Manual• WaveScan Operator’s Manual• Professional Use Information• Patient Information Booklet

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Agenda

Introduction to the STAR S4 IR Excimer Laser System

Introduction to CustomVue

Refractive Labeling

Pre-Operative Evaluation

WaveScan System Review

Surgical Planning

STAR S4 IR Excimer Laser System Calibration

STAR S4 IR Excimer Laser System Hardware Overview

Surgical Technique

STAR S4 IR Excimer Laser System Conventional Ablations


The STAR S4 IR Excimer Laser System is a 193 nm Excimer laser system capable of delivering

• Conventional (manifest refraction based) Treatments• Wavefront Guided Treatments• Therapeutic Treatments


STAR S4 IR Excimer Laser System Components

• Top Hat (non Gaussian) 193 nm beam• 3 D ActiveTrak eye tracking system

For Wavefront Guided Treatments the following features are available

• Iris Registration (IR)• Variable Spot Scanning (VSS)• Variable Repetition Rate (VRR)

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CCD Camera Lenslet Array

Outgoing Wave CCD-Image

WaveScan System Hartmann-Shack Wavefront Aberrometer

Components of the CustomVue Procedure

CustomVue Procedure

The CustomVue procedure is a wavefront guided treatment

There are three components to the CustomVue procedure

1.WaveScan WaveFront system to measure the wavefront of the eye

2.WaveScan Software to reconstruct the wavefront and calculate ablation instructions that are transferred to the S4 IR System

3.S4 IR Excimer Laser system that will execute the ablation instruction

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WaveScan CustomVue Software:• Proprietary VISX smart pulse-packing software

Zernike ReconstructionUsed for Review

Fourier ReconstructionUsed for Treatment

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STAR S4 IR Excimer Laser System

• 100% Variable Spot Scanning treatment with automatic centering and Iris Registration


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Advantages of the CustomVue Procedure

Optical zone adjustabilityVariable spot scanning and thermally balanced treatments with better adherence to an individualized target shapesAvailability of compensation for cyclorotation and compensation for pupil centroid shiftDirect transfer (USB) of patient treatment data to the laser to reduce transposition errors

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Higher Order Aberrations and the CustomVue Treatment

There is no clinical data to suggest Higher Order pre-operative RMS should be considered when deciding to perform wavefront - guided ablations

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Refractive Labeling

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Refractive Labeling

Physicians should refer to the STAR S4 IR Excimer Laser System Operator’s Manual for a complete discussion of FDA approved Labeling for LASIK and PRK.

The following slides review labeling and are not intended to be a complete or comprehensive review.

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Refractive Indications

The VISX STAR Excimer Laser System with Variable Spot Scanning (VSS™) and the WaveScan WaveFront System is indicated for wavefront-guided laser assisted in situ keratomileusis (LASIK):

• In patients who are 21 years of age or older• With refractive stability

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The STAR™ Excimer Laser System is indicated for Photorefractive Keratectomy (PRK):

• In patients who are 18 years of age or older for the treatment of spherical myopia up to - 6.00D

• In patients who are 21 years of age or older for the treatment of myopic astigmatism and hyperopic astigmatism ( see slide 14 for full approved range)

• With refractive stability

Refractive Indications

CustomVue LASIK Treatment Ranges

Sphere Cylinder Spherical Equivalent

Myopic Astigmatism

-11.75 -3.75 -11.75

Hyperopic Astigmatism

+3.75 +2.75 +3.75

Mixed Astigmatism

X +0.25 to +5.75 X

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Conventional PRK Treatment Ranges


Myopic Astigmatism

-12.00D -4.00D -12.00D


+5.00D +4.00D +6.00D

Mixed Astigmatism

NA NA NA

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Conventional LASIK Treatment Ranges


Myopic Astigmatism

-14.00D -5.00D -14.00D


+5.00D +3.00D +6.00D

Mixed Astigmatism

X <6.00D X

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Refractive Stability

Stable manifest refraction as evidenced by less than or equal to the following change in either spherical or cylindrical component of manifest refraction over the previous year is required.• Myopia: ±0.50D • Hyperopia: ± 1.00D• Mixed Astigmatism: ±1.00D • High Myopia: ±1.00D

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Contraindications

Laser refractive surgery based on a CustomVue treatment, Conventional LASIK or Conventional PRK is contraindicated in:• Patients with collagen vascular, auto-immune or immunodeficiency

diseases• Women who are pregnant or nursing• Patients with signs of keratoconus or abnormal corneal topography• Patients who are taking the following medications:

– Isotretinoin (Accutane®)– Amiodarone hydrochloride (Cordarone®)

Accutane is a registered trademark of Hoffman-La Roche, Inc.Accutane is a registered trademark of Hoffman-La Roche, Inc.Cordarone is a registered trademark of SanofiCordarone is a registered trademark of Sanofi

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Warnings

LASIK or PRK is not recommended in patients who have:• Diabetes• A history of Herpes simplex or Herpes zoster keratitis• Significant dry eye that is unresponsive to treatment• Severe allergies

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ELECTROMAGNETIC FIELD (EMF): The thyratron emits an electromagnetic pulse which is shielded by the metal coverings of the STAR S4 IR Excimer Laser System. This metal covering reduces the EMF below the limits set by applicable standards for electromagnetic compliance.

WARNING: The effects of electromagnetic emissions from the excimer laser system on other devices, such as cardiac pacemakers or implanted defibrillators, are unknown. Operation of the laser in proximity to such devices is not recommended.

Warnings

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Precautions

The safety and effectiveness of the STAR S4 IR Excimer Laser System has not been established in:

• Patients with corneal neovascularization within 1.0 mm of the ablation zone

• LASIK and PRK patients under the age of 21 years– With the exception of PRK patients who are 18 years of age or older for the

treatment of spherical myopia up to - 6.00D

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The safety and effectiveness of the STAR S4 IR Excimer Laser System for LASIK correction have not been established in patients with:

• Progressive myopia, hyperopia or astigmatism• Ocular disease, corneal abnormality, previous corneal or

intraocular surgery, or trauma in the ablation zone• A history of glaucoma• Residual corneal thickness < 250 microns at the completion of the

ablation• The medication Sumatriptan (Imitrex®)

Imitrex is a registered trademark of GlaxoSmithKlineImitrex is a registered trademark of GlaxoSmithKline

Precautions

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To avoid corneal ectasia, the posterior 250 microns of the corneal stroma should not be violated by the laser or the microkeratome

Patient pachymetry - (Non-nomogram adjusted depth of treatment + flap thickness) = > 250 microns

Precautions

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The safety and effectiveness of this laser for wavefront guided LASIK correction have not been established in patients with:

• WaveScan-measured pupil size < 5.0 mm

Precautions

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The safety and effectiveness of wavefront- guided LASIK surgery have only been established:• In Myopia with an optical zone of 6.0 mm and an ablation zone

of 8.0 mm• In Hyperopia with an optical zone of 6.0 mm and an ablation

zone of 9.0 mm• In Mixed Astigmatism with an optical zone of 6.0 mm and an

ablation zone of 9.0 mm

Precautions

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All CustomVue treatments should be performed with humidity between 40-45% and the temperature between 68 - 72° F.The anticipated post-operative keratometry value in any meridian must be >34D to < 50D.

Precautions

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During the FDA CustomVue clinical trial for highly myopic eyes, an "in the stromal bed" pachymetric measurement was performed to assure a minimum residual stromal bed of 250 microns.

Precautions

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Patient Information Booklet and Professional Use Information

Prospective patients, as soon as they express an interest in laser vision correction and prior to undergoing surgery, must receive from the treatment provider the Patient Information Booklet.

Prior to undergoing surgery, prospective patients must be informed of the alternatives for correcting their refractive error including eyeglasses, contact lenses, and other refractive surgeries.

All surgeons should read the Professional Use Information prior to performing procedure procedures with the STAR S4 IR Excimer Laser system.

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FDA Reporting Requirement Abbott MDR Program

Abbott is required by law to report any of the following events (MDR = Medical Device Reporting)

Serious Injury or Death

• Permanent impairment of a body function• An injury that necessitates medical or surgical intervention by a

health care professional• A malfunction occurred that if it were to reoccur may likely cause or

contribute to death or serious injury

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FDA Reporting Requirements MedWatch Program

In addition to the MDR Report Abbott is required to file,

users are required to file

Form FDA 3500A

“MedWatch Mandatory Reporting”

For more information, call the DSMA at (800)638-2041

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Pre-Operative Evaluation

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Pre-operative Examination

Baseline evaluation of patients requesting CustomVue or Conventional treatments should be performed within 30 days of laser refractive surgery

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Discontinuance of Contact Lenses

Soft lenses - discontinue lens wear at least two weeks prior to examination and treatment

Hard (PMMA) or RGP lenses - discontinue lens wear at least three weeks prior to examination and treatment with stable topography (keratometry) and refraction• 3 topographic maps (central keratometry readings) and MR

taken at 1 week intervals. The last two readings must not differ by > 0.5D

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Discontinuance of Contact Lenses

Contact Lenses cause:

– Reversible corneal topographic changes– Alterations in corneal thickness

Contact Lenses must be discontinued prior to CustomVue treatments to allow these reversible corneal changes to resolve

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Sequence of Pre-Op Exams Wavefront-Guided Treatments

WaveScan System KeratometryCorneal TopographyWaveScan Guided Manifest RefractionSLE/Tonometry/PachymetryCycloplegic RefractionDFEPost-Cycloplegic Refraction• If necessary

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WaveScan Exams

WaveScan exams with 6.0 mm wavefront diameter are preferred for treatments• The minimum size of the wavefront diameter must be >5.0

mm to calculate a CustomVue treatment• Measurements with a wavefront diameter <5.0 mm will be

unavailable for selection

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WaveScan Adjusted Manifest Refraction (WAMR)

Obtain a WaveScan exam at the beginning of the pre-operative evaluation prior to other measurements

Place the WaveScan cylinder measurement (axis and magnitude) in the phoropter or trial frame

Refine the sphere to yield the most letters read with the least minus

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Uncorrected Visual Acuity

Refraction (WAMR)

• Manifest Refraction– Myopia - resolution based, not contrast based end point of

refraction• least minus to see most letters

– Astigmatism - Jackson Cross Cylinder - maximize magnitude of cylinder

– Hyperopia - Pushed Plus technique

Best Spectacle Corrected Visual Acuity

• Do not stop at 20/20

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Astigmatism

Refractive, keratometric and topographic cylinder occasionally do not match in axis or magnitude

Treatment is based on WaveScan and/or Manifest cylinder

When disparity occurs, proceed very cautiously and ascertain stability by repeated measurements over time

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Cycloplegic Refraction

Cycloplegic Refraction (1% cyclopentolate)

True cycloplegia reduces accommodation and allows evaluation of:

• an over-minused myope • maximal hyperopia (manifest and latent)

Only refine the sphere during the cycloplegic refraction

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Comparison Between Sphere and Cylinder Myopia

Difference between WaveScan and manifest sphere or cylinder powers must be within +/- 0.50D

Difference between manifest and cycloplegic sphere or cylinder powers must be within +/- 0.50D

Difference between WaveScan and cycloplegic sphere or cylinder powers must be within +/- 0.50D

For eyes with > 0.50D cylinder, the manifest cylinder axis must be within 15° of the WaveScan cylinder axis

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Comparison Between Sphere and Cylinder Hyperopia/Mixed Astigmatism

Difference between WaveScan and manifest sphere or cylinder powers must be within +/- 0.75D

Difference between manifest and cycloplegic sphere or cylinder powers must be within +/- 0.75D

Difference between WaveScan and cycloplegic sphere or cylinder powers must be within +/- 0.75D

For eyes with > 0.50D cylinder, the manifest cylinder axis must be within 15° of the WaveScan cylinder axis

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Keratometry

Keratometry is required Manual K’s preferredAuto K’s are acceptableSimulated Topography K’s are sub-optimal

K1 = flat KK2 = steep KK2 Axis= axis of steep K

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Pupillometry• Bright and dim illumination measurement

Corneal Topography - necessary in all patients

• R/O Keratoconus or any other abnormality• R/O CL related abnormalities• Verify post-operative results

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Slit Lamp Exam

Tonometry

Pachymetry

• Ultrasonic pachymetry required for LASIK/PRK Dilated Media and Fundus Exam

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Residual Posterior Stroma

There must be at least 250 microns of stroma remaining following the ablation to prevent iatrogenic keratoectasiaThe flap does not provide tectonic support to the cornea post LASIKThe following calculation must be done prior to treatmentCentral Corneal Thickness - (Flap Thickness + Ablation Depth) must be > 250 microns

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Residual Posterior Stroma

The ablation depth should be based on the actual depth of the non-nomogram adjusted myopic desired correction as this is indicative of the amount of tissue that is effectively removed

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WaveScan System Review

Take Take WaveScWaveScan an MeasuremMeasurem

entent

DesignDesignCustomVueCustomVueTreatmeTreatment nt

Perform Perform CustomVueCustomVueTreatmentTreatment

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Surgical Planning and Surgical Technique

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Surgical Planning and Technique

“Everything that goes on in and around the laser room is the responsibility of the operating surgeon !!!”

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STAR S4 IR Excimer Laser System Nomogram Development

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WARNING

The following nomogram recommendations serve as a guideline for Conventional and CustomVue procedures with the STAR S4 IR Excimer Laser System

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The following nomogram recommendations are made based on adherence to the refraction techniques, treatment dimensions, surgical techniques and environmental conditions discussed in the STAR S4 IR Physician Certification Course

WARNING

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Nomogram Warning

Nomograms developed for other laser systems CANNOT be used with the STAR S4 IR Excimer Laser System.

Nomograms for Conventional and CustomVue procedures are different.

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Initial CustomVue Nomogram Recommendations

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CustomVue Ablation Dimensions

The safety and effectiveness of wavefront- guided surgery have only been established • In Myopia with an optical zone of 6.0 mm and an ablation zone of 8.0

mm• In Hyperopia with an optical zone of 6.0 mm and an ablation zone of

9.0 mm• In Mixed Astigmatism with an optical zone of 6.0 mm and an ablation

zone of 9.0 mm

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CustomVue Ablation Dimensions

Procedures performed with different treatment dimensions may yield different (i.e., less predictable) results• Enlarging the Optical Zone will result in deeper ablations that take

more time to deliver• Enlarging the Ablation Zone will result in longer treatments

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CustomVue Nomograms

Myopia

• Nomograms for CustomVue myopic LASIK typically involve an increase in the WaveScan sphere relative to the manifest refraction

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CustomVue LASIK for Myopia

WaveScan Spherical Equivalent < -6.00D

• Use Physician Adjustment to bring the WaveScan Sphere to the Manifest Sphere

• Add 0.25D more minus ( Physician Adjustment of -0.25D) in patients younger than 35 years of age

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CustomVue LASIK for Myopia

WaveScan Spherical Equivalent > - 6.00D

• Use Physician Adjustment to bring the WaveScan Sphere to the Manifest Sphere

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CustomVue LASIK Hyperopia and Mixed Astigmatism

Hyperopia and Mixed Astigmatism

• No adjustment if the WaveScan and Manifest Sphere are within 0.75D

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Refining Your CustomVue Nomogram

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Refining Your Nomogram

It is expected your individual nomogram may differ from our initial recommendations

In order to develop an individualized nomogram, a careful retrospective analysis of your refractive results is required

This retrospective analysis should be made based on data obtained after the point of refractive stability (see below)



Myopic Astigmatism 1-3 months

Hyperopic Astigmatism 3-6 months

Mixed Astigmatism 3-6 months

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Patients must be refractively stable prior to modifying your nomogram

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Nomogram Development

Many factors may influence individual nomograms• Temperature• Humidity • Patient age• Patient refractive error• Microkeratome• Elevation• Surgical technique

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Adjusting Your Nomogram

Start out slowly with nomogram modifications

Change one variable at a time

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The Use of the Percentage Nomogram Adjustment

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CustomVue Percentage Nomogram Adjustment

The Percentage Nomogram Adjustment allows the surgeon to make a percentage adjustment to the entire WaveScan-defined ablation (includes that HOA’s)

• A maximum adjustment of ±10% is allowed • The Percentage Nomogram Adjustment is programmed on

the Design screen

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Percentage Nomogram Adjustment

DesignDesign screen screen with detail of with detail of

Nomogram FieldNomogram Field

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The Percentage Nomogram Adjustment does not change the shape of the ablation

• A greater or lesser number of pulses are used to achieve the WaveScan-defined target shape (including higher and lower order terms)

• As a result, the Percentage Nomogram Adjustment does not affect the calculated depth (Maximum Ablation Depth)

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The Percentage Nomogram Adjustment should be used to compensate for results based on individual differences in environmental conditions and surgical technique after a critical review of refractive results

The Percentage Nomogram Adjustment is preferred for nomogram adjustment purposes because it adjusts the entire wavefront treatment (not only the sphere)

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The Percentage Nomogram Adjustment is different than the Physician Adjustment

• The Physician Adjustment allows you to adjust the spherical component of the WaveScan refraction by +/- 0.75D

• The Physician Adjustment can be used as an endpoint adjustment to deviate from emmetropia

– e.g., planned post-operative target of -0.25 in a 55 year old patient

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One method to produce a percent nomogram adjustment which may be used with the following calculation:

For each CustomVue patient perform the following calculation post-operatively

(Post -Op MRSE )/ (Pre-Op WaveScan equivalent)x100)

Calculate the mean percent for all CustomVue patientsPlease note that the above is intended as an example and does not represent the only valid method for determining a percentage nomogram adjustment

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Pre-Op WaveScan Equivalent

Post-Op

MRSE

Post Op MR /Pre-WaveScan x 100

Patient 1 -5.00 -0.25 +5.0%

Patient 2 -4.75 +0.25 -5.26%

Patient 3 -5.50 -0.50 +9.09%

Mean % +2.94%

For Demonstration Purposes only> 50 eyes are recommended for this

analysis

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STAR S4 IRExcimer Laser System Calibration

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System Calibration Requirements

Complete calibration is required each day when the system is powered up

Abbott requires that a –4.00 D sphere calibration be tested after every third ocular treatment

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Fluence Calibration

Fluence calibration adjusts the laser system energy to maintain a constant delivered fluence of 160 mJ/cm2.

• Fluence calibration is performed:– at system startup– before each patient treatment procedure (with the exception of fellow eyes)– any time the operator selects SET FLUENCE on the Lens Calibration screen

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System Calibration

Calibration Platform with Calibration Plastic

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Lens Calibration

•Myopic Sphere•Myopic Cylinder•Flat/Block•Flat•Hyperopic Sphere•Centering

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Lens Calibration

ActiveTrak™ System Calibration in conjunction with Beam Centering required

•The ActiveTrak System Calibration and Beam Centering are accessed on the Lens Calibration screen by selecting “Centering”.

•The ActiveTrak System aligns the treatment center as defined by the eye tracker in relation to the laser beam. Beam centering, done in conjunction with the ActiveTrak System calibration, aligns the reticle in relation to the laser beam. This test ablation must be done as a part of daily calibration procedure.

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Reticle Alignment

Check the laser beam/reticle alignment

Reticle adjustment knobs

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STAR S4 IR Excimer Laser System Hardware Overview

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Laser Safety

Emergency Stop Button

Know where the EMERGENCY STOP button is located

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Laser Safety

The Premix cylinder contains Argon and Fluorine

• Fluorine is toxic

High voltage (25,000 to 32,000 volts)

Never operate the laser in the presence of flammable anesthetics or other volatile substances such as alcohol

Nominal hazard zone is 40 cm

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Variable Spot Scanning

Combines advantages of larger and smaller diameter beams

Allows tissue to be removed in the shortest possible time

Smooth ablation

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Variable Repetition Rate

The repetition rate will vary from 6 to 20 Hz for CustomVue treatments

VRR will allow optimal delivery of Variable Spot Scanning (VSS) pulses to ablate tissue in a temporally and thermally efficient fashion

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Environmental Conditions

Control of environmental conditions during CustomVue treatments is important

Temperature should range from 68 to 72º F

Relative humidity should range from 40% to 45%

Stability of temperature and humidity is important

• Humidity lower than 40% can lead to overcorrections • Humidity higher than 45% can lead to undercorrections

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Laser Repetition Rate

Conventional Ablations and Phototherapeutic Ablations

• User can vary Repetition from 1.5 to 10 Hz

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Performing the CustomVue Treatment

On the STAR Excimer Laser System, select the appropriate CustomVue Treatment by selecting the patient’s name on the Main Menu screen.

The CustomVue Treatment calculated on the WaveScan System will appear.

The treatment parameters cannot be changed on this screen.

Review the information on the laser computer screen to ensure that it is correct.

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Flap Hinge Location

Select Flap Hinge Location•Superior•Nasal•Temporal

LASIK flap hinge location must be entered on the Operating Parameters screen for each CustomVue™ treatment when using the IR system

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Performing the CustomVue Treatment

After verifying that this is the appropriate treatment, select TREAT to perform the patient treatment.

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Patient Alignment

Fiducial Line

•When the patient is seated in the patient chair, align the patient’s head perpendicular to the system with the fiducial line

Fiducial Line Button

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MicroscopeWild Leica Microscope• Variable Magnification

– 0.63x– 1.0x– 1.6x– 2.5x– 4.0x

All treatments should be performed at 1.6x magnification

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Doctor’s Keypad

Doctor’s KeypadDoctor’s Keypad

IR ButtonIR Button

ActiveTrakActiveTrak™™ButtonButton

Fiducial Line

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Joy Stick

Joy Stick controls the position of the Patient Chair

• The microscope does not moveFarther = faster

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VisionKey Card

VisionKey Cards are purchased from AMO

Allow use of the STAR S4 IR Excimer Laser• VisionKey Cards are laser specificThere are different VisionKey Cards for

• Conventional Ablations• CustomVue Ablations• CustomVue Retreatments• PreVue Lenses• Phototherapeutic Keratectomy

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Patient Chair

Automatic OD/OS pre-positioning

Automatic “Y” center button

Pillow evacuation button relocated to the left side of the headrest

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Operative Illumination

Ring Illumination - allows visualization of stromal surface

Oblique Illumination - allows visualization of iris and pupil

Ring Illumination

Oblique Illumination

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Operative Illumination

Adjust the operative illumination to keep operative pupil diameter as close as possible to WaveScan pupil diameter (between 5 and 7 mm)

Use the lowest level of illumination possible to • allow patient comfort • help with patient fixation on the flashing

fixation target

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ReticleReticle is projected into each ocular

Reticle can be turned off during • Flap creation/reposition• Epithelial RemovalThe Reticle must be on to proceed with the ablation

Reticle brightness can be adjusted

Reticle Dimensions

• Inner Ring 4mm• Middle Ring 6mm• Outer Ring 9mm

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Aspirator

Aspirator can be moved out of position to allow

• Creation/reposition of LASIK flap• Removal of corneal epitheliumThe Aspirator must be in the proper position to proceed with the ablationAIRBORNE CONTAMINANTS: Airborne contaminants which are produced by the ablation process are captured in proximity to the cornea near the point of production and fed into an aspirator with a filter. This aspirator is designed to prevent any of the products of ablation from contaminating the surgical suite.

Aspirates over 99% of material ejected from the cornea during the ablation

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Laser Footswitch

Laser Footswitch has two positions

• First position activates the aspirator• Second position activates the laser

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ActiveTrak Eye Tracking System

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The ActiveTrak System should be used during Conventional and CustomVue Procedures

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Moves the laser beam to compensate for eye movements

3D infrared eye tracker

Side-mounted infrared cameras monitor x, y, and z (up and down) motion


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Side-mounted, infrared cameras monitor x, y, and z movements

Oblique IR lighting does not interfere with procedure


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Eye movements during LASIK/PRK are followed by the ActiveTrak system such that it:

• Continues to monitor between pulses

• Checks eye position at least 3 times for every pulse delivered to the cornea


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The surgeon can choose to set the treatment center manually or use the automatic centering mode.

If using automatic centering, the ActiveTrak will locate the pupil and set the treatment center.

Automatic Centering should always be used when performing CustomVue Procedures


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ActiveTrak Use

Press ActiveTrak Button on Doctor’s Keypad

The entire reticle will begin flashing

The ActiveTrak Eye Tracking System will locate the pupil and set the treatment center

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Once the pupil is located, the outside ring on the reticle will stop flashing

Once the treatment center is set, the center cross of the reticle stops flashing.

The ActiveTrak System will maintain this position throughout the treatment

ActiveTrak Use

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Fully depress the laser footswitch to begin the treatment

The center cross of the reticle will flash slowly during the treatment when the ActiveTrak System is on and tracking the pupil

When the ActiveTrak System is activated, you may use the joystick to correct for head (translational) motion during the treatment

Do NOT use the joystick to correct for eye rotation when the eye tracker is activated

ActiveTrak Use

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Treatment will stop or pause when the ActiveTrak™ System detects the following conditions:• The patient’s eye moves more than 1.5 mm from the surgeon-

selected treatment center (the initial position from which the ActiveTrak™ System begins tracking).

• The vertical position (z axis) of the corneal surface moves more than 2.0 mm from the initial treatment position.

• The pupil diameter is not circular to within 32% or becomes smaller than 1.5 mm or larger than 6.0 mm during treatment.

• Eye motion exceeds 0.2 mm between video frames.• Dark objects or reflective objects are in the ActiveTrak™ System’s

field of view.• Surgical instruments or the surgeon’s hands cross the ActiveTrak™

System’s field of view.

ActiveTrak Use

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Components of Iris Registration

Compensation for Cyclorotation

Compensation for Pupil Centroid Shift

Ozone Compensation

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Registration of CustomVue AblationsWaveScan exams are acquired with the patient in the upright position

The CustomVue ablation is performed with the patient in the supine position

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Registration of CustomVue Ablations

Iris Registration is necessary to compensate for cyclotorsion that occurs when the patient goes from the upright to the supine position

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Iris Registration Basic Principles

The image of the patient’s eye taken on the WaveScan System is transferred to the STAR S4 IR System along with the CustomVue treatment files via a USB Flash Drive

The amount of cyclotorsion of the eye under the laser is determined by comparing features of the iris on the WaveScan image to the same features of the iris on the STAR S4 IR camera image

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The iris registration system is only available for CustomVue treatments

Re-registration for intra-operative cyclotorsional movement• If surgeon tracks significant intra-operative movement, iris

image can be re-registered under the laser


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There are 48 landmarks used for matching the two iris images24 landmarks on the WaveScan iris image are matched with 24 landmarks on the STAR S4 IR laser image One landmark for each 15 degree iris sector in each image is identifiedA minimum of 21 of the 24 landmarks must matchIt is possible that the laser software will NOT be able to identify enough (or similar) landmarks to allow iris registration to work, regardless of the quality of the WaveScan image


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Find multiple matching reference points for each iris section

WaveScan Image

Laser Image


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Torsional AngleCalculate the torsional angles from

multiple measurements


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Compensation for Pupil Centroid Shift

Wavefront measurements and wavefront- guided ablations are typically done under different lighting conditions

As a result, the pupil size may be different during measurement and ablation

When the pupil size changes the pupil centroid usually shifts

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Pupil Centroid Shift Different Lighting Conditions

Diagnostic measurement (mesopic)Diagnostic measurement (mesopic) LVC Treatment (photopic)LVC Treatment (photopic)

As the pupil changes size, its centroid may not remain stationary, relative to the outer iris boundary

Outer Iris BoundaryOuter Iris Boundary

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Iris Registration system compensates for pupil centroid shift by referencing to the outer iris boundary and consistently centering wavefront ablations on the same WaveScan pupil centroid at the laser

Iris Registration Compensation for Pupil Centroid Shift

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Ozone Compensation

Ozone Compensation – • As ozone builds up it decreases the amount of energy that

passes through the optical pathway • Ozone compensation increases energy stability• Prior to treatment (patient/plastic) the system will fire ten

laser pulses• Note: you will hear these additional shots prior to treatment

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Iris Iris Registration WaveScan WaveScan AcquisitionAcquisition

Acquisition of high quality WaveScan images is essential to the success of IR

WaveScan Eye Images must be in clear focus with iris details easily visible to facilitate iris capture

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When capturing the WaveScan Eye Image, there must be maximum exposure to facilitate proper iris capture

– No eyelid artifacts– Little or no cilia– Small lacrimal menisci

• WaveScan acquisition must be properly centered• Visible Purkinje reflections must be crisp and clear

Iris Iris Registration WaveScan WaveScan AcquisitionAcquisition

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A distance of at least 1mm (preferably more) is recommended between the pupil boundary and the upper and lower eyelids

Iris Registration WaveScan Acquisition

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WaveScan Acquisition

Iris and pupil overlays displayed by the software need to match the appropriate structures in the Eye Image The outer iris boundary must be clearly visible and overlying the visible limbal region• Eye Images with any boundary misplaced should not be

used for treatment

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Iris RegistrationIris RegistrationWaveScanWaveScan®® Acquisition Acquisition

Outer Iris Boundary

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Outer Iris Boundary (OIB)

Misplaced outer iris boundary can occur at the WaveScan System and/or the laser

Both images must be monitored and actively verified

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Iris Registration Iris Registration WaveScanWaveScan Acquisition

Surgeons must view the actual exam used for treatment designThe Green Box in the bottom of the Eye image display indicates that the quality of the selected WaveScan exam is eligible for IR at the laserAs the criteria at the laser for IR are more stringent than at the WaveScan, it is possible that IR might not engage at the laser with the green box present

IR Eligible IR Not Eligible

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Iris Registration Surgical Technique

Flap Hinge Location•Superior•Nasal•Temporal

LASIK flap hinge location must be entered on the Operating Parameters screen for each CustomVue treatment when using the IR system to identify outer iris boundary

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Iris Registration Surgical Technique WARNING

As with any surgical procedure, it is ultimately and entirely theresponsibility of the surgeon to ensure that the CustomVue treatment loaded on the STAR S4 IRSTAR S4 IR System belongs to the correct eye of the correct patient positioned under the laserThe "WaveScan Image: Verified" display is an additional criterion used to determine that the WaveScan image associated with the selected treatment matches the image of the patient's eye under the laser• Iris matching technologies are probability-based and should not be

solely relied on for verification

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Iris Iris Registration

Prior to engaging the IR system

• Make certain no surgical instruments or devices are obscuring the IR camera view of the iris, pupil or outer iris boundary– Do not use a Chayet drain or any similar device that can obscure the outer iris

boundary or other ocular landmarks– Keep your hands from obscuring the IR camera

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Prior to engaging the IR system

• With the eyelid speculum in position, make certain the cornea is in the middle of the inter-palpebral fissure (primary position)

• Ensure that the patient’s head is centered and is not tilted to either side

• Eliminate shadows on the iris or pupil by properly positioning the patient’s head

Iris Iris Registration

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Iris Registration Optimal Iris Registration Optimal Surgical Environment EnvironmentOperative Illumination• Adjust the operative

illumination to keep operative pupil diameter as close as possible to WaveScan pupil diameter (between 4 mm and 7 mm)

• Use the lowest level of illumination possible to – allow patient comfort – help with patient fixation on the

flashing fixation target

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Optimal Surgical Optimal Surgical Environment

Change the illumination as little as possible or preferably not at all after the ActvieTrak System and IR have been engaged.

If illumination is changed after engaging the ActiveTrak System and IR, consider restarting the ActiveTrak System and IR

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Center the patient’s eye under the laser and focus on the corneal surface • The pupil and iris detail will be slightly out of

focus when the laser is properly focused on the corneal surface

• The IR infrared camera is focused on the iris even though the surgeon is focused on the corneal stromal surface

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Procedure should be performed at magnification 16x (the microscope dial may read 16 or 1.6, depending on the system microscope model)


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Significant cyclorotation can occur after the flap is lifted

Therefore, Iris Registration and ActiveTrak must be engaged AFTER the flap has been lifted


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Iris Registration Technique Activation of IR System

Doctor’s Keypad

IR ButtonIR Button

ActiveTrakActiveTrakButtonButton

Turn on the IR System by pressing the Rotation (Rot) button and the ActiveTrak™ System by pressing the Track button on the Doctor’s Keypad

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Iris Registration Technique Activation of IR SystemIR should be turned on by pressing the “ROT” button before the ActiveTrak System is activated

• The ActiveTrak System must be on and tracking to use IRIR will then automatically start when the ActiveTrak System is on and tracking

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Patient cooperation and fixation is critically important while IR is engagingAnything that interferes with patient cooperation and fixation while IR is engaging will • increase the time of IR capture• reduce the success of IR capture


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IR can be re-initiated at any time during the treatment by turning IR off and back on using the “ROT” button

When Iris Registration is turned off, the cyclorotation correction and pupil centroid shift are returned to a zero position, just as if Iris Registration had never been on in the first place


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Once IR has been engaged DO NOT reposition the patient’s head

If the patient moves after IR has been engaged, IR MUST be restarted


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The dialog box will add the message:

• “Treatment Registered to WaveScan References. Press footswitch to start treatment.”

Fully depress the laser footswitch to begin the treatment

• This will automatically restore the live microscope camera image


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Iris Iris Registration Technique Technique

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Optimizing Iris Registration Three strikes

Strike One

• Check Patient Alignment• Confirm Microscope Magnification at 1.6x• Focus on anterior stromal surface• Re-engage IR

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Strike Two• Decrease Illumination• Re engage IR

Strike Three• Increase Illumination• Re engage

If still unsuccessful after three attempts at engaging IR, proceed with CustomVue ablation without IR

Optimizing Iris Registration Three strikes

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STAR Excimer Laser System Conventional Ablation Dimensions & Shapes

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Beam Shaping

Iris Diaphragm

• 2 mm to 6.0 mm diameter for PTK • 6 or 6.5 mm diameter for PRK/LASIK Slit Blades

• PTK (0.6 mm to 6.0 mm)• Hyperopic PRK (scanning slit)Iris Diaphragm/Slit Blades

• PRKa 6 x 4.5 mm or 6.5 x 5.0 mm (minimum minor axis) ellipse

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Variable Spot Scanning

• Blend ZoneVariable Slit Scanning

• Hyperopia• Hyperopic Astigmatism

Beam Shaping

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Ablation Dimensions & Shapes

Spherical Myopia• Standard Zone 6.0 mm• Larger Zone 6.5 mmMyopic Astigmatism (Ellipse)

• Standard Zone 6.0 x 4.5 mm (minimum minor axis)• Larger Zone 6.5 x 5.0 mm (minimum minor axis)

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Myopic Astigmatism

The width of the ellipse is determined by the relationship between sphere and cylinder• for any given sphere, the less the cylinder the larger the

minor axisLarger Zone treatment depth is 15-20% more than Standard Zone

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Ablation Dimensions & ShapesBlend Zone• Used in combination with Myopic/Myopic Astigmatic Ablation• Can be used with Standard or Larger Zone treatment• Last diopter of spherical myopia is treated at 8.0mm diameter • Must have one diopter of spherical myopia at the corneal plane

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Blend Zone Option with VSS Treatment Profile

1.0 mm 1.0 mm

Ablation Diameter

Blend ZoneBlend Zone

8.0 mm

Creates gradual slope from optical zone to un-ablated cornea

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Blend Zone Option with VSS How Does It Work?

Last -1.00 D is treated at 8.0 mm

• e.g. -6.00 D with Larger Zone and Blend Zone Option Selected– - 5.00 D at 6.5 mm

– -1.00 D at 8.0 mm

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Treatment Algorithms Myopia

< 6.00 D Single Zone

• 6.0 mm(Standard) • 6.5 mm(Larger)> 6.00 D to <12.00 D Multi-zone

– 6.0/6.5 mm– 5.5 mm diameter

> 12.00 D Multi-zone

– 6.0/6.5mm– 5.5mm– 5.0mm

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Myopia/Astigmatism Treatment screen

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Myopia/Astigmatism Treatment Screen

Desired correction field• Enter amount of myopia and astigmatism to be

eliminated during the treatment• Enter axis of astigmatism• Enter vertex distance• Enter Ks if not previously entered

– (Ks affect the number of pulses delivered to cornea)

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Myopia / Astigmatism Treatment ScreenA value must be entered in the astigmatism field even if it is zero

Results Field• Summarizes pulse rate, depth and number of pulses

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Myopia with Astigmatism Desired Correction Field

The computer will accept a plus cylinder manifest refraction or a minus cylinder manifest refraction in the desired correction field at the spectacle plane

NOTE: The final treatment is corrected for the refractive error at the corneal plane expressed in minus cylinder

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Ablation Dimensions & Shapes

Hyperopia

• Ablation Diameter 9.0 mm• Correction Diameter 5.0 mm

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Hyperopia/Astigmatism Ablation Profile

In order to produce a steeper central cornea, the peripheral cornea is flattened

Astigmatism is corrected by differentially steepening the flat axis

Eccentrically rotating lens in hyperopia module displaces laser beam out to 9 mm

Slit blades shape laser beam to rectangular scanning slit

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Hyperopia Ablation Profile

The ablation extends out to 9.0 mm

The zone of deepest treatment is at approximately 5 mm (but may be varied from 3 to 6 mm)

Ablation depth at 5 mm is ~ 8 microns/diopter

• Maximum depth approximately 50 microns

0.8 mm0.8 mm

Optical zone - 5 to 6 mmOptical zone - 5 to 6 mm

Ablated area - 9.0 mmAblated area - 9.0 mm

Transition zoneTransition zone

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Hyperopia/Astigmatism Treatment Screen

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Hyperopia/Astigmatism Ablation Diameters

All U.S. clinical trials were conducted at 9 mm total diameter and 5 mm diameter zone of correction

No clinical evidence for use of any other size zone. Smaller zones may adversely affect the patient’s optical performance

Always verify pupil diameter in bright and dim illumination before treatment

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Mixed Astigmatism Cross Cylinder Ablation

Cylindrical Steepening with Cylindrical Flattening

Example: -1.00 +3.00 x 090

Hyperopic Cylinder Surface Power+2.00 x 090

Myopic Cylinder Surface Power -1.00 x 180

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Cross-Cylinder Ablation Profile

Cylindrical Steepening with Cylindrical Flattening

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Treatment Preferences Page

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STAR Excimer Laser SystemActiveTrak System Software

Any default can be overwritten

Surgeon MUST verify all data in every field in every screen

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Patient Manager Patient Information Screen

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Select Treatment Button Pre-Op Screen

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Pre - Operative Examination Screen Refraction Warnings

and Yellow bar on bottom left of screen says“ No manifest refraction”

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Operative Parameters Screen

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Notes Screen

N.B., Epithelium

Removal is for

information on the

Operative Report

Only - Does Not

Control Treatment

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Epithelium Removal Screen

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Treat Button

Treat Button can only be

selected from treatment

screens

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Treatment Summary Screen

physicain training slidesmay 25-3 final nov 7 2012.ppt

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