DICOM 2003: Expanding the standard’s Scope

Andrei Leontiev

Chairman, Working Group 6

IDX Systems Corporation

DICOM 2003 Vital Statistics

11 new Supplements since publication of DICOM 2001

63 Correction Items Major development of new IODs Final Text of DICOM 2003 is available for

download free of charge from DICOM web-site:– http://medical.nema.org

Major focus of DICOM in 2002

Security– De-identification, Clinical Trials

Applications of structured reporting (DICOM SR) – Evidence documents:– Chest CAD– Cath Lab Reporting– OB-GYN, Vascular US, Echocardiography

Major focus of DICOM in 2002

New Media– DVD-R, E-mail attachments, large capacity MODs

New Objects– Multi-frame MR

– New CT, XA, VL – WG2 and WG13 re-activated

JPEG 2000 Configuration Management Standard Maintenance

Security – De-Identification

Supplement 55 Allows the creator or sender of the objects

to remove PHI without breaking standard requirements for Type 1, Type 2 attributes

Reversible – creator may keep original PHI in the object encrypted to prevent unauthorized access or exposure of information

Security – Clinical Trials

Supplement 70 – builds upon the mechanisms of de-identification

Added Attributes to Information Object Definitions that allow creators identify subject, site, protocol and other clinical trial attributes in the SOP Instances submitted as part of a trial.

Considers possibility of adding the trial identification attributes to an object at different points in workflow

Clinical Trials Workflow

ScannerScannerScannerScanner

PACS

Workstation

CTCC

Add CTI at site scanner

Add CTIat PACS

Add CTI at siteworkstation

Add CTI at CTCCworkstation

DICOMInbox

DICOM Push DICOM Push Database

Add CTIat CTCC

Media&

Film

Translation Scanning

DICOMDIR

Buffer

FTP/e-Mail

Courier

Translation Transfer

Submission

QA/QC

Quant & Analysis

Blinded Read

CTI = Clinical Trial Identification AttributesCTCC = Clinical Trial Coordinating Center

Clinical Trial Site Clinical Trial Coordinating Center

Content Mapping Resource

Defines and maintains DICOM Context groups - semantically-related collections of terms from SNOMED, LOINC, SCPECG, BI-RADS, UCUM

Includes large collection of DICOM-managed terms and DICOM templates

Extensive work with SR and coded terminology called for more rigid rules for use, maintenance and extension of DCMR

Content Mapping Resource

WG 8 is charged with maintaining the DCMR and serving as liaison to other terminology development bodies – SNOMED, LOINC, HL7

WG6 keeps overall oversight authority on supplements

No Supplements featuring coded terminology work will be put for Letter Ballot until all terminology issues are solved by WG8 and/or related bodies.

Chest CAD

New SR-based specialized SOP class. Extensive use of templates. Builds on the mechanisms defined for

Mammography CAD Separation into a SOP Class allows for precise

control of the document’s structure Introduced several templates that are being utilized

by other SR-based SOP Classes– Measurements– Image library

Ultrasound Procedure Reporting

A number of supplements covering different areas of US procedure reporting:– OB-GYN (Final Text)

– Vascular (Public Comment)

– Echocardiography (Public Comment)

Further advances the concept of Evidence Documents – objects generated by machine, that are not images but are carrying the supplemental information for the procedure to aid in diagnosis

Cath Lab Reporting

Another example of Evidence Document object for Hemodynamics, and Electrocardiography Reporting

Introduces templates for Cath Lab reports Also introduces the new Service Class for

Procedure Logging– Allows equipment to identify the log events to the

centralized logging system– Logs extensive amount of information collected by cath

lab devices

New Imaging Objects

Supplement 49 – Multi-frame MR Similar approach for Multi-frame CT –

Supplement 58 New efforts in development of enhanced

Angiography and Projection Radiography objects – WG2 has been re-activated

Multi-frame MR

New object definition supporting latest advancements in MR technology

Support for very large data sets, split of an acquisition between several multi-frame objects

New concepts – functional groups Workshop on the subject at SPIE 2003

Workflow in Radiotherapy

Major effort by WG7 – still several months away from Public Comment

Development of the workflow concepts and mechanisms for radiotherapy

Based on the General Purpose Worklist Service Classes

Likely to add ability to “push” work to systems such as Calculation Servers

Workflow in Radiotherapy

Host Archive Workflow Manager

Performing Application

Store SOP Instances

Request Calculation (N-EVENT-REPORT)

Get GPSPS Transmit SOP Instances for Input and Relevant Information

Update GPSPS (IN PROGRESS)

Create GPPPS (IN PROGRESS)

Set GPPPS (COMPLETED)

Update GPSPS (COMPLETED)

Store Results

Request Calculation Status

Create GPSPS

Standard Maintenance

63 Correction Items – ranging from typos to “jumbo patches” of recent definitions– Introduction of support for Chinese and UNICODE

Retirement of obsolete portions of the standard:– ISO Networking

– Point-to point connectivity – Parts 9, 13

– Storage Commitment Pull Model

– Overhaul and modernization of Part 1

Configuration Management Supplement 67 – in trial-use phase Introduces use of LDAP and standardizes LDAP

schema for maintenance of configuration parameters of DICOM devices

LDAP query to retrieve configuration parameters from LDAP server

Introduces use of industry standards – DNS, NTP, DHCP along with LDAP to support flexibility and robustness of configuration management

Configuration Management Covers most significant use cases:

– Installation and auto-configuration of a new device

– Portable devices

– Mobile devices

– Small networks

– Mixed networks with legacy equipment

Main objective is to decrease service cost while maintaining reliable standard-based configuration management

New Transfer Syntaxes & Media

New content (SR) requires different compression algorithms - Internet-standard “deflate” (zlib) transfer Syntax is added for SR Objects.

Many old JPEG syntaxes have never been used; retired but 4 of old JPEG syntaxes

Added JPEG 2000 (Jan 2002). WG13 resumed work on adoption MPEG as

DICOM transfer syntax for Visual Light objects

New Transfer Syntaxes & Media New Media Technologies and requirements of

applications prompting support for large-capacity media:– DVD-RAM– DVD-R (Public Comment)– 640 MB, 1.3 GB, 2.3 GB 90mm MODs– 4.1 GB 130 mm MODs

Internet e-mail is profiled like media (files and filesets) DICOM MIME type (application/dicom) is registered

with IETF

Conformance Huge Effort was put into overhauling existing Par 2 –

Conformance (Public Comment) New, more refined conformance Statement structure:

– Includes Executive Summary– Mandatory sections on error handling, coded terminology,

security Main objective is to enhance readability of the

statement and interoperability of products New, much more comprehensive sample conformance

statements reflecting specifics of different service classes

DICOM Object Access via Net In addition to the e-mail distribution of DICOM

objects, DICOM recently spearheaded joint Work Item with ISO TC215 – Web Access to DICOM Persistent Objects (WADO)– In early stages of development

– Will allow for web-access to images utilizing standardized URL

– In conjunction with standardized MIME type should allow for access using a Web Browser

DICOM and other standards

Joint Working group (WG20) with HL7 (Imaging Integration SIG), works on harmonization of DICOM and RIM, templates, imaging order and procedure definitions.

Agreement between DICOM and SNOMED WG10 works with ISO TC215 WG2 Liaison with JPEG

DICOM and other standards

Continued cooperation with IHE:– General Purpose Worklist chosen as basis for

Post-Processing Integration Profile (Year 4), Reporting Workflow Profile (Year 5)

– New Evidence Documents Profile to embrace similar concept recent DICOM SR

Joint Work with IHE, HL7, ASTM on the Common Audit Log mechanisms

New supplements in the works New SR-based objects:

– More US Evidence Documents– New Service Class to Query for Patient History– Breast Imaging Report

3D and n-D imaging:– Spatial Registration– Multi-Dimensional Interchange– 3D Ultrasound

Hanging Protocols

Conclusion

16 parts of official DICOM 2003 edition are available at http://medical.nema.com

DICOM is well positioned to continue serve integration needs of medical imaging, including workflow, evidence information recording, effective access to imaging results

Active cooperation with other standards assures DICOM objects integration into future HER – whether by reference, or through well-defined trans-coding mechanisms.