Strategic Document
Revision 1.06, July 6, 2001
The purpose of this document is to provide a summary of the current activities and future directions of the DICOM standard. The content of the document is largely based on information submitted by individual working group chairs. WG10 will update this document on an annual basis and submit it for review and approval by the DICOM Committee at the committee’s annual RSNA meeting.
A Brief Background of the DICOM Standard
The introduction of digital medical image sources in the 1970’s and the use of computers in processing these images after their acquisition led the American College of Radiology (ACR) and the National Electrical Manufacturers Association (NEMA) to form a joint committee in order to create a standard method for the transmission of medical images and their associated information. This committee, formed in 1983, published in 1985 the ACR-NEMA Standards Publication No. 300-1985. Prior to this, most devices stored images in a proprietary format and transferred files of these proprietary formats over a network or on removable media in order to perform image communication. While the initial versions of the ACR-NEMA effort (version 2.0 was published in 1988) created standardized terminology, an information structure, and unsanctioned file encoding, most of the promise of a standard method of communicating digital image information was not realized until the release of version 3.0 of the standard in 1993. The release of version 3.0 saw a name change, to Digital Imaging and Communications in Medicine (DICOM), and numerous enhancements that delivered on the promise of standardized communications.
The DICOM standard now specified a network protocol utilizing TCP/IP, defined the operation of Service Classes beyond the simple transfer of data, and created a mechanism for uniquely identifying Information Objects as they are acted upon across the network. DICOM was also structured as a multi-part document in order to facilitate extension of the Standard. Additionally, DICOM defined Information Objects not only for images but also for patients, studies, reports, and other data groupings. With the enhancements made in DICOM (Version 3.0), the Standard was now ready to deliver on its promise not only of permitting the transfer of medical images in a multi-vendor environment, but also facilitating the development and expansion of picture archiving and communication systems (PACS) and interfacing with medical information systems.
Scope of DICOM
The DICOM Standards Committee exists to create and maintain international standards for communication of biomedical diagnostic and therapeutic information in disciplines that use digital images and associated data. The goals of DICOM are to achieve compatibility and to improve workflow efficiency between imaging systems and other information systems in healthcare environments worldwide. DICOM is a cooperative standard. Therefore, connectivity works because vendors cooperate in testing via scheduled public demonstration, over the Internet, and during private test sessions. Every major diagnostic medical imaging vendor in the world has incorporated the standard into their product design and most are actively participating in the enhancement of the standard. Most of the professional societies throughout the world have supported and are participating in the enhancement of the standard as well.
DICOM is used or will soon be used by virtually every
medical profession that utilizes images within the healthcare industry. These include cardiology, dentistry,
endoscopy, mammography, opthamology, orthopedics, pathology, pediatrics,
radiation therapy, radiology, surgery, etc.
DICOM is even used in veterinary medical imaging applications.
Technology Overview
The DICOM Standard addresses multiple levels of the ISO OSI network model and provides support for the exchange of information on interchange media. DICOM currently defines an upper layer protocol (ULP) that is used over TCP/IP (independent of the physical network), messages, services, information objects and an association negotiation mechanism. These definitions ensure that any two implementations of a compatible set of services and information objects can effectively communicate.
Independence from the underlying network technology allows DICOM to be deployed in many functional areas of application, including but not limited to communication within a single site (often using various forms of Ethernet), between sites over leased lines or virtual private networks (VPNs), within a metropolitan area (often using ATM), across dial-up or other remote access connections (such as by modem, ISDN or DSL), and via satellite (with optimized protocol stacks to account for increased latency).
At the application layer, the services and information objects address five primary areas of functionality:
· Transmission and persistence of complete objects (such as images, waveforms and documents),
· Query and retrieval of such objects,
· Performance of specific actions (such as printing images on film),
· Workflow management (support of worklists and status information) and
· Quality and consistency of image appearance (both for display and print).
DICOM does not define an architecture for an entire system; nor does it specify functional requirements, beyond the behavior defined for specific services. For example, storage of image objects is defined only in terms of what information must be transmitted and retained, not how images are displayed or annotated. DICOM can be considered as a standard for communication across the “boundaries” between heterogeneous or disparate applications, devices and systems.
The services and objects that are defined in DICOM are designed to address specific, real-world applications (such as the performance of an imaging study on an acquisition device). As such, DICOM is not a general-purpose tool for distributed object management. In general, information is transferred “in bulk” according to a “document” paradigm.
By contrast, general-purpose standards for distributed object or database management generally provide lower level, more atomic access to individual attributes. Though the DICOM standard does provide the so-called “normalized” services for patient and study management, these have not proven popular, and the “composite”, document-oriented, services have prevailed. This is mostly likely a consequence of the natural division of functionality between different vendors, devices and applications. For example, the ability to “set” or “change” a patient’s name is generally implemented in a proprietary and centralized manner. To safely distribute responsibility for such a change across boundaries between different applications requires more underlying support than DICOM currently possesses (such as support for transactions and two-phase commitment).
At the present time, the pressing needs in DICOM (as indicated by the priorities of the various working groups) are to address issues relating to security, performance, new modality technology, and workflow management. These needs are being successfully addressed using the conventional “underlying” DICOM technology. Where there are interfaces to standards based on other technologies (such as HL7 V2.x and 3), the focus for harmonization is on a shared “information model”. It may be the case that the nature of the underlying technology needs to be revisited in the future, whether it is to make use of more sophisticated off-the-shelf distributed object management tools such as CORBA, or less sophisticated encoding tools such as XML. However, the current priority is to address improvements in functionality to better meet the needs of the end-user, rather than to adopt an alternative technology for the sake of it. This priority is continually reinforced by a desire to remain compatible with the installed base of equipment.
When specific new technology is required, such as in support of new features such as security and compression, the strategy is to adopt proven international, industry or de facto standards. Accordingly, network confidentiality and peer authentication in DICOM are provided by the use of either TLS (an Internet standard) or ISCL (an ISO-based standard). Similarly, rather then develop medical-image-specific compression schemes, DICOM adopts standards developed by ISO/IEC JTC 1/SC 29/WG 1 such as JPEG and JPEG 2000. For interchange media, standard file systems compatible with conventional software (such as ISO 9660 and UDF) are used.
DICOM’s Relationship to Other Standards
Throughout the development of DICOM, much attention was devoted to establishing working relationships with other related standard initiatives throughout the world. The initial version of the standard leveraged prior work by ASTM. The Internet protocol TCP/IP was adopted in 1993. In the nineties, solid cooperation with CEN, the European Committee for Standardization, resulted in a number of jointly developed supplements. In parallel, the convergence of a Japanese interchange media format (IS&C) with DICOM required much joint work where JIRA, the Japan Industries Association of Radiological Systems played a major role. In the USA, DICOM participated in the early coordination efforts for healthcare standards with the ANSI-HISBB from which DICOM adopted a harmonized patient name structure, and started progressively to define links with HL7. This cooperation has now entered in a very active phase with the creation, in 1999, of a joint DICOM-HL7 working group. Finally, it was a logical step for DICOM to establish a Type A liaison with the ISO Technical Committee 215 at its creation in 1999. ISO TC 215 has decided not to create an imaging working group, but to rely on DICOM for bio-medical imaging standards.
DICOM is also focusing its attention to the evolution of standards linked to the Internet. DICOM strategy is to integrate Internet Recommendations as soon as they are stable and largely disseminated in consumer commercial products. In this evolution, much care is taken to ensure that the consistency of the DICOM standard is maintained with its large installed base. DICOM already uses standard healthcare enterprise intranets and soon the e-mail exchange of DICOM objects (Standard MIME type) should be possible. It is clear that the use of DICOM objects and services in commonly used information technology applications will grow in the future.
DICOM’s Organizational Structure
DICOM is a standards organization administered by the NEMA Diagnostic Imaging and Therapy Systems Division. The complete bylaws of the DICOM Standards Committee are available on the NEMA web site at www.nema.org. Working groups of the DICOM Committee perform the majority of work on the extension of and corrections to the Standard. Working groups are formed by the DICOM Committee to work on a particular classification of tasks. Once formed, working groups petition the DICOM Committee to approve work items for which the working group will execute the plan delineated in the work item. Once the output of a work item (generally a supplement or correction proposal) has been completed, it is submitted to Base Standards Working Group (WG6), for their review. Supplements to the standard then go through a public comment period, after which the DICOM Committee authorizes the supplement for letter ballot by DICOM members. Letter ballots require approval by two-thirds of those voting affirmative or negative and return of more than one-half of the ballots sent to members in good standing relative to letter ballots. Since the working groups perform the majority of work on the extension of and corrections to the Standard, the current status and future directions of the DICOM standard are best represented by review of each working group.
The DICOM Standards Committee and its Working Groups
|
|
|
The DICOM Standards Committee
Secretariat NEMA
Secretary Howard Clark, NEMA
Vendor Co-Chairman David Clunie, M.D. ComView Corporation
User Co-Chairman Lloyd Hildebrand, M.D., American Academy of Ophthalmology
Date of Last Update: July 6, 2001
Scope:
The DICOM Standards Committee exists to create and maintain international standards for communication of bio-medical diagnostic and therapeutic information in disciplines that use digital images and associated data. The goals of DICOM are to achieve compatibility and to improve workflow efficiency between imaging systems and other information systems in healthcare environments worldwide.
Working Group 1 (Cardiac and Vascular
Information)
Secretariat NEMA
Secretary Howard Clark, NEMA
Co-Chairman Jon Elion, MD, FACC, Heartlab
Co-Chairman Harry Solomon, GE Medical Systems
Date of Last Update: July 6, 2001
Scope:
To develop standards for the digital interchange of the cardiovascular images, physiologic waveforms and core clinical information, which characterize a patient undergoing a catheterization procedure.
Roadmap:
The WG1 roadmap is a long-term strategy to specify information objects and services to fully digitize and integrate data flow within and beyond the catheterization laboratory. The ultimate goal is a comprehensive digital cardiovascular record for the patient, of which the cath lab record is a significant part.
The cath lab is a multi-modality mix of many types of equipment from many different manufacturers. Moreover, cardiovascular medicine requires consultation and interaction between many medical disciplines. Standardized data interchange is critical in this environment.
The initial WG1 work effort was directed toward the definition of X-ray Angiography (XA) image exchange, including both a Basic Cardiac profile and a 1024 profile for media-based exchange. The next step was the development of DICOM cardiovascular waveform exchange, with specializations for hemodynamics, cardiac electrophysiology, and electrocardiography. Completing the data acquisition aspect is definition of intra-vascular ultrasound (IVUS) image exchange.
The next level of integration involves definition of various structured data interchanges in the cath lab, to support the interpretation and effective use of the basic images and waveforms. This structured data includes procedure logs, quantitative and qualitative measurements, and clinical reports, and requires specialization of the DICOM Structured Report services.
Finally, the overall workflow management of the cath lab within the cardiology department and within the larger institution will be evaluated. This will be done with regard to adapting the DICOM Study Management services to the particular needs of cardiology practice (as distinct from radiology).
Short Term Goals:
Completion of DICOM standards for IVUS image exchange, currently in Public Comment.
Specification of IODs, Templates, and SOP Classes for cath lab structured reports:
· Hemodynamics
· Quantitative Coronary and Ventricular Analysis
· Cath Lab Procedure Log
· Electrocardiography
· Cath Lab Clinical Report
Drafts templates are available for prototyping and demonstration.
Technical support for public demonstrations of DICOM for the cardiovascular community.
Current Status:
WG1 plans to meet approximately four times per year for 1-2 days each, plus interim discussions by telephone conference.
Current Work Items:
IVUS (Supplement 48)
Cath Lab Structured Reports (pending approval)
Risks:
The integrated data flow in the cath lab requires the implementation of multiple DICOM Services in the equipment, such as DICOM image and waveform interchange, and various types of structured reports. It will be important to establish a forum (not necessarily within WG1) that will promote the adoption of comprehensive interoperation profiles for the cath lab, similar to the effort of IHE in radiology.
Further, the various types of objects must be synchronized to provide clinically meaningful and accurate data acquisition. For example, IVUS images must be accurately synchronized to ECG and audio waveforms, and to the procedure log, to post-process for 3-D reconstruction and to be able to identify the sites imaged and the acquisition context. These multiple objects of different SOP classes must be effectively managed as a coordinated whole, and effective technical mechanisms for inter-equipment synchronization need to be developed.
Most of WG1’s current work is based on DICOM Structured Reporting, which is new and as yet unproven in practice. This presents several risks to the work of WG1:
· DICOM SR relies extensively on coded terminology and templates. There remain both practical and theoretical questions regarding the processes for development, distribution, and maintenance of code sets and templates for the cath lab SR information objects.
· DICOM SR does not currently support a means of controlling presentation, similar to Grayscale Presentation State for images. Rendering of SR is a major area for development, and substantial inter-product differences in presentation may affect the acceptance of SR by the clinical community.
· Tool support for DICOM SR is still rudimentary. This may be an impediment to adoption of SR information exchange.
· SR involves formalizing and standardizing much clinical knowledge, which has hitherto been informal or ad hoc. Development of SR templates thus requires much more involvement from the clinical community, as well as willingness by that community to adopt standardized formats over custom local formats.
Challenges and Opportunities:
The WG1 effort has the potential to significantly improve the operation of the catheterization laboratory, with consequent improvement in both patient care and facility administration. Major improvements in lab productivity and clinical response time to emergent cardiovascular conditions can result from integrated data flow within and between the cath department and the hospital. This integration includes both data moving into the lab (e.g., demographics, blood lab results), and data moving out (e.g., images and reports to the emergency department). The structured coding of cath lab data can facilitate analysis and improvement of patient outcomes, quality assurance, automated support for billing, as well as administrative analysis of organizational effectiveness. Beyond the institution, this data can support broad clinical research and regional or national clinical data registries.
The work effort must studiously adhere to the roadmap for progressive and incremental integration of the cath lab data flow, focusing on pragmatic next steps in the standardization process which bring real benefit to the cardiovascular user community (clinicians and administrators). A major challenge will be developing standards that facilitate the conversion of legacy cath lab systems to DICOM standard data interchange. The standards must be effective even in environments that have a mix of fully DICOM-compliant subsystems and legacy systems that may support only a limited subset of DICOM functionality.
Strong participation in WG1 from the European Society of Cardiology, as well as the American College of Cardiology, has helped ensure a broad international applicability of the work. It is critical to maintain this liaison and engagement.
Working Group 2 (Digital X-Ray) – This working group is not currently active
Secretariat
Secretary
Chairman
Date of Last Update: July 6, 2001
Scope:
To develop a DICOM standard for digital projection radiography.
Working Group 3 (Nuclear Medicine)
Secretariat NEMA
Secretary Richard Eaton, NEMA
Chairman Jeff Pohlhammer, Marconi Medical Systems
Date of Last Update: July 6, 2001
Scope:
To develop standards for the digital interchange of Nuclear Medicine and PET images.
Roadmap:
Potential work items would be generation of CPs to address the above-mentioned short-term goals.
Short Term Goals:
The chairman is currently trying to activate the committee so that several items can be addressed. These include:
· Identification and publication of the SNOMED terms currently in use for required coded attributes in the NM IOD. These were circulated among vendors at the time this IOD was created, but new implementers of this IOD have difficulty determining which SNOMED terms are applicable.
· Identification and publication of SNOMED terms that can be used for some of the optional coded attributes in the NM IOD. Of particular interest are terms that can be used to describe the image view (i.e. LAO, Vertical Long Axis, etc) and to identify imaging conditions such as stress/rest. The former would be applied to the View Code Sequence, which is already part of the NM IOD. The latter may need to be included in a new (optional) attribute.
· Clarification of several items in the NM IOD that are commonly misunderstood, such as clarification of when the Image Position and Image Orientation attributes are required.
Current Status:
This WG has been inactive for a while. The chairman has requested that the secretary contact committee members to schedule a teleconference.
Current Work Items:
None.
Risks:
None, yet.
Challenges and Opportunities:
Outside groups, such as the SNM (Society of Nuclear Medicine) have recently become more interested in DICOM, and have expressed concerns related to the issues mentioned above. This presents an opportunity to work with the SNM, and other related groups, to address these issues in a manner consistent with the architecture of the current NM IOD. The challenge is to do so in a timely manner.
Working Group 4 (Compression)
Secretariat NEMA
Secretary Howard Clark, NEMA
Chairman Alan Rowberg, MD, University of Washington (ACR)
Date of Last Update: July 6, 2001
Scope:
To provide data compression facilities for the DICOM standard and to advise on application or object-related definitions of data compression parts of the DICOM Standard created by other working groups.
Roadmap:
Develop appropriate DICOM transfer syntaxes for JPEG 2000 when it is released.
· Expected release of JPEG 2000 Part 1 is December 2000
Expectations for the next few years, after the current work items are finished:
· JPEG 2000 (ISO 15444-1 CD stage)
· lossless & lossy progressive wavelet
· MPEG-2 (WG 12)
· M-JPEG 2000?
· Retirement of unused 10918-1 processes
Use of Future Image Schemes
· Network
· any transfer syntax can be negotiated
· uncompressed default baseline
· compressed baselines?
· Media
· general purpose uncompressed
· XA/CT/MR 10918-1; US RLE & 10918-1
· future - Mammo DVD JPEG-LS ? 2000 ?
Future schemes for other data
· Single bit (scanned document)
· CCITT Fax
· JBIG
· JBIG2
· Overlays
· Waveforms (if not combined with images)
· Audio
· Future JPEG 2000 work
Beyond JPEG 2000 Part 1 (ISO 15444-1)
· Part 2 extensions (may not be royalty free)
· 3D transform (multi-slice or multi-spectral)
· Line/block based coders (major IPR issues)
· More Region-of-Interest modes
· Part 2 lags 6-9 months behind part 1
Short Term Goals:
We plan to serve a maximal number of modalities and clinical situations, with support for growing areas such as telemedicine and the use of new technologies such as DVD. We will develop the appropriate DICOM transfer syntaxes for JPEG 2000 when it is released.
Current Status:
Compression that is already available in the standard:
JPEG (ISO 10918-1) - all processes
· lossy (DCT)
· lossless
· sequential, progressive
· Huffman, arithmetic entropy coders
RLE (aka TIFF Packbits)
· ultrasound
JPEG-LS (ISO 14495-1) (DICOM CP-174)
· lossless, lossy (“near-lossless”)
Current Work Items:
Tracking the progress of the JPEG 2000 standard, evaluating its performance in medical imaging, and planning to develop appropriate DICOM transfer syntaxes for JPEG 2000 when it is released.
Risks:
The risk of JPEG 2000 not issuing as an international standard is low. We expect no problems in creating the proper transfer syntaxes. The success of other items will depend on support from the DICOM vendor community.
Challenges and Opportunities:
Multi-frame and 3D compression.
WG 12 is making progress on the incorporation of MPEG compression into the DICOM Standard. We now have a technical expert on MPEG to assist us in our work. The first phase of our work is to determine whether MPEG really offers considerably greater compression ratios and/or performance for Ultrasound cine than Lossy JPEG or JPEG 2000 compression. We have been concentrating on MPEG2 and have found that one of the key issues is the limited capability of most decoders. Most current MPEG2 decoders can only handle certain image frame sizes. We need to investigate this issue further to determine if we want to create a transfer syntax for MPEG2 with restricted allowable image frame sizes.
Relationships to other Standards:
DICOM has cross-representation to JPEG 2000.
WG 5 (Exchange Media)
Secretariat NEMA
Secretary Howard Clark, NEMA
Chairman David Clunie, ComView Corporation
Date of Last Update: June 12, 2001
Scope:
To develop DICOM standards for interchange media.
Roadmap:
Potential work items with respect to new types of media:
· Larger capacity MOD media are widely used but not actually recognized in the standard, both for 90mm and 130mm
Potential work items with respect to secure media:
· WG 14 has an assigned work item to develop media security proposals, currently at either the file or attribute level; the possibility of using a secure file-system has been raised and OSTA has begun work on Secure UDF; should this become a reality then WG 5 will need to review the implications of incorporating Secure UDF in PS 3.10, 3.11 and 3.12
Potential work items with respect to the DICOMDIR:
· Opportunities exist to improve or replace the DICOMDIR to better support:
· Large number of small files
· Longer file names (such as those based on UIDs)
· A “.dcm” extension
· Security features
Potential work items with respect to archival
· At present DICOM only defines interchange media, not archive media
· DICOM PS 3.10 files (+/- DICOMDIR) are frequently used on optical archive media, both removable and in jukeboxes
· A proposal from the VA has been received to consider defining an “archive migration format” to facilitate migrating studies from obsolete archives to new devices
Short Term Goals:
· Consideration of DVD media beyond existing DVD-RAM support
· Consideration of 130mm 4.xGB CT/MR profile proposal
· Consideration of 90mm > 640MB US profile proposal
· Consideration of Secure UDF proposal (with WG 14)
Current Status:
· Supplement 40 completed May 2001, after conversion to support DVD-RAM only
· Progress on DVD-R stalled awaiting developments in optical media industry, specifically:
· More than one DVD-R vendor (expected 3Q 2001)
· Support/requirement from application-specific WG
Current Work Items:
· None
Risks:
Roadmap - new types of media:
· MOD vendors are few, especially in 90mm
· Larger capacity 130mm based on 512 bytes per sector and FAT 16 file system are extremely wasteful of space (e.g. 4.1GB vs. 5.2GB); use of non-partitioned file system causes problems with NT but is required for backward compatibility
Roadmap - secure media:
· Secure UDF effort has just begun, has yet to attract widespread OS support, and place role in the consumer market is unclear; there is talk of “special drives” with hardware keys which would not be acceptable for medical apps (could not leverage consumer volume)
Roadmap - DICOMDIR:
· Any significant changes would impair compatibility with installed base, and suggested changes may only be of benefit to implementers rather than users
Roadmap – archival:
· Choices of archive media and format are usually based on such factors as access time, transfer rate, durability and cost, rather than interoperability, and DICOM has never been considered to have a role in standardizing these choices
· Migrating “internal” media from a decommissioned archive is a recognized and difficult problem, but still may not justify standardization
Challenges and Opportunities:
· Leverage the popularity of consumer optical media formats like DVD, when versions that can be written actually do become popular
· Leverage the popularity of consumer logical file system formats like UDF
· Leverage consumer and internet standards for media security solutions, such as Secure UDF
Relationships to other Standards:
An “informal” liaison with OSTA exists to harmonize efforts with respect to UDF, MOD and DVD
WG 6 (Base Standard)
Secretariat NEMA
Secretary Howard Clark, NEMA
Chairman Andrei Leontiev, IDX Systems Corporation
Date of Last Update: June 12,2001
Scope:
WG6 maintains the overall consistence of the DICOM standard. Some of the responsibilities include:
· Execution the DICOM Maintenance Process (Correction Proposals). The process is used to make “corrections and minor changes” to the current versions of the Standard.
· Provision of technical coordination and guidance for all WGs. This includes review and official approval before the Public Comment, Letter Ballot, and Final Text draft releases of all supplements.
· Development of Supplements to the standard related to Print, Image Management, etc.
· Coordination of joint development efforts with CEN, JIRA, and Medis DC.
· Coordination with NEMA for the publication of DICOM.
Roadmap:
On-going DICOM Maintenance Process:
· Correction Proposals submitted by the members and other interested parties will continue to be considered by the WG6
· All Correction Proposals accepted by WG6 and designated for inclusion into voting package, will be published on the FTP server for the comments by all DICOM Committee members at least 2 weeks before the WG6 meeting considering such voting package for Letter Ballot
Potential work items of other Working Groups:
· WG6 will provide assistance to the working groups working on their assigned work items
· All work items (as supplements to DICOM Standard) approved by corresponding working groups will be accepted for review by WG6 and for preparation of Letter Ballot.
· All Supplements approved by the Letter Ballot will be considered in order to prepare Final Text, with addressing of any comments received
Potential work items with respect to Workflow Management:
· WG 6 is considering potential work items that may address areas of Medical Imaging Workflow that may require development of new or improved mechanisms, in such areas as:
o Hardcopy Management
o Archive Management and Image Availability Notifications
o Support for Patient Information Reconciliation (update of information in composite instances)
Potential work items with respect to the Structured Reporting:
· SR implementations may require introduction of new or improved mechanisms to address such functionality as:
o Query/Retrieve
o Search – ability to retrieve information from SR instances or to identify SR instances with particular content in the document content tree
Potential work items with respect to Conformance:
· Development of Conceptual Model and XML Schema for DICOM Conformance Statement, example of XML-based statements
Short Term Goals:
· Finalize work on retirement of obsolete parts of the Standard (Part 9, Storage Commitment Pull Model)
· Revision of Part 2 - DICOM Conformance
· Consideration of Configuration Management
Current Status:
The following Supplements developed by WG6 have recently been completed and are in Final Text :
· Supplement 53
· Supplement 54
· Supplement 57
· Supplement 59
· Supplement 64 – Revised Part 2 (Conformance) – Released for Public Comment
Current Work Items:
· Supplement 44 – Retirement of Part 9
· Supplement 67 – Configuration Management
· Supplement 68 – Retirement of Storage Commitment Pull Model
Risks:
Challenges and Opportunities:
Relationships to other Standards:
Progress of the IHE initiative is being regularly reviewed by WG6.
WG 7 (Radiotherapy)
Secretariat NEMA
Secretary Stephen Vastagh, NEMA
Chairman David Murray, TomoTherapy
Date of Last Update: July 6, 2001
Scope:
To develop and maintain radiotherapy information objects for the DICOM Standard and promote their implementation and acceptance within the industry.
Roadmap:
In the next few years, the RT-specific objects in the standard need to be maintained to completely stabilize existing implementations. Extensions to existing objects have been and will be introduced to accommodate new techniques. Proton therapy will be addressed. The next major goal is to address how workflow in the RT department can be enhanced using existing and upcoming DICOM objects and concepts, in particular General Purpose Worklist.
Short Term Goals:
The primary work of WG7 involves maintenance of existing RT-specific DICOM objects, correcting issues discovered during detailed implementation, introducing minor extensions to deal with new techniques and approaches in radiotherapy. In addition, approximately 6 additional CPs have been incorporated into the standard, and another three are in the current voting packet.
Current Status:
Supplement 11 (RT Image, RT Structure Set, RT Dose, RT Plan) and Supplement 29 (RT Treatment Record objects and Media Support) are part of the DICOM 1999 standard onwards.
Current Work Items:
A number of new CPs are under discussion, extending brachtherapy and external beam therapy, correcting some errors and clarifying wording. Extension of DICOM to handle proton therapy is being worked on and a draft proposal exists. Extension of query/retrieve to require object-level attributes critical for RT applications is underway. In addition, work has begun on defining a calculation service model within the DICOM context that will allow a central service such as a dose calculation engine to receive calculation requests via a “push” model rather than a polling model as currently supported by the standard.
Risks:
Implementation of existing standardized objects is well advanced, and implementation of DICOM objects is now an essential marketing requirement for products in the radiation oncology market. There is no clearly identifiable risk to achieving short-term goals.
Challenges and Opportunities:
Smooth incorporation of RT procedures into DICOM workflow concepts, in particular General Purpose Worklist and Modality Performed Procedure Step. Development of a calculation service model for RT that is generally applicable within the DICOM standard.
Relationships to other Standards:
RT objects use IEC-61217 for treatment machine descriptions, and ICRU concepts for dosimetry. The DICOM patient-based coordinate system also has a well-defined relationship to the IEC Patient coordinate system, recently introduced into IEC documentation. Another IEC document entitled “Guidelines for Implementation of DICOM in Radiotherapy (IEC 62C/277/NP) is also under development.
WG 8 (Structured Reporting)
Secretariat College of American Pathologists
Secretary Karen Kudla, SNOMED
Kkudla@cap.org
Chairman Cameron Brackett, Cyberpulse LLC
cbrackett@clinical-knowledge.com
Date of Last Update: July 6, 2001
Scope:
To develop and maintain the DICOM Structured Reporting specification, and to collaborate with DICOM working groups and other standards development committees in the development of specialized reports and other documents based on the generic SR specification.
Goals:
A.
Create a set of guidelines for template creators.
B.
Support the creation of general, reusable templates
components and outlines
C.
Maintenance
of the SR infrastructure
D.
Cross-specialty
SR template creation
E.
Development
of a methodology (with a standardized graphical notation) to describe
templates.
F.
Assist
WG 20 in the integration of DICOM SR with other standards efforts, in
particular HL7, and support of SR development in the various DICOM WGs.
G.
Technical
support for demonstration of SR, as required by IHE, NEMA, etc.
H.
Development a process for submitting clinical use cases and
requirements for SR templates
I.
Development
of a means of specifying SR presentation
J.
Development
of a formal syntax for encoding the definition of templates and context groups
in efforts to facilitate creation of a machine-readable version of these parts
of the standard.
Current Status:
Kick-off meeting held June 6th
Work Items:
- Standard Measurement template (associated with Part 16)
- Clinical history (associated with Part 16)
Risks:
TBD
Challenges and Opportunities:
A. Identify issues retarding SR template creation
B. Identify commonalities in SR template creation in efforts to create cross modality SR template consistency
C. Identify a process for communicating work.
D. Identify WG 20 and WG 6 AHG relationship
E. Change Proposals
Relationship
to Other Standards:
- HL-7
- SNOMED
- LOINC
- UCUM
- ISO-TC215
- CEN-TC251
- ACR
WG 9 (Ophthalmology)
Secretariat American Academy of Ophthalmology
Secretary Flora Lum, M.D.
Co-Chairman Lloyd Hildebrand, M.D., American Academy of Ophthalmology
Co-Chairman Rainer Waedlich, IFA Systems Group
Date of Last Update: January 24, 2001
Scope:
To address all issues relating to imaging and reporting of image-based studies in ophthalmic applications.
Roadmap:
The implementation of ophthalmology relevant objects (e.g. VL, SR, U/S) will be emphasized in eye care environments. Coordinated education and demonstration projects for vendors and users will be essential to get broad adoption of the standard in eye care. Extensions/refinements to existing objects will be introduced to accommodate new techniques. Visual field and corneal topography will be addressed.
Current Work Items:
· Refinement of Modality Worklist to accommodate the workflow of eye care environments, which require many ad hoc studies, provided "on demand"
· Creation of templates for Structured Reporting
· Evaluation of existing objects or current work items for use in visual field and corneal topography applications
Risks:
Implementation of existing standardized objects is just beginning. While there has been heightened awareness of DICOM in the vendor and user communities, many major vendors still do not participate in the standard development process or use the standard in their products.
Relationships to other Standards:
Working Group 9 anticipates working closely with SNOMED in the development of structured terminology for use in Structured Reporting object for ophthalmic applications.
WG 10 (Strategic Advisory)
Secretariat NEMA
Secretary Howard Clark, NEMA
Chairman Cor
Loef, Philips Medical Systems
Cor.loef@philips.com
Chairman Joel Chabriais, Societe Francaise de Radiologie
joel.chabriais@nck.ap-hop-paris.fr
Date of Last Update: July 6, 2001
Scope:
To consider issues and opportunities related to the strategic evolution of DICOM; to provide liaison to other standards developing organizations; to review standards and technology in healthcare, biomedical imaging, commerce, telecommunications, and informatics; and to develop and maintain the long-term strategic plan of the DICOM Standards Committee.
Roadmap:
· Advice the DICOM Committee on the influence of technology advances on DICOM, e.g. streaming video.
· Advice the DICOM Committee on possible actions related to Healthcare security regulations.
· Coordinate the relation between DICOM and ISO TC 215.
· Advice the DICOM Committee about the relation and possible actions resulting from the IHE (Integrating the Healthcare Enterprise) initiative of RSNA and HIMSS.
· Explore and guide the evolution of DICOM Structured Reporting in relation to the progress in HL7 Clinical Document Architecture and web-developments such as XML.
· Explore and advice the DICOM Committee about the influence of Web-technology on DICOM.
Short Term Goals:
· Complete DICOM position paper on the relation between Structured Reporting and XML in the light of the HL7 Roadmap for Clinical Document Architecture.
· Complete DICOM Mime type (Supplement 54) and explore DICOM URL.
· Complete the 1st version of the DICOM Strategic Document.
· Advice the DICOM Committee on Coding Schemes for non-US countries.
Current Status:
· 1st version DICOM Strategic Document completed by Dec. 2000
Current Work Items:
See Short Term Goals
Risks:
· The integration of DICOM with other standards is becoming an increasingly important point, however the maturity of such standards (e.g. HL7 V3.0) is a complex process, on which DICOM has little influence.
Challenges and Opportunities:
Challenges:
· Acceptance and development of Structured Reporting also outside the strict DICOM community.
· The rapid development of web-based distribution of healthcare information. The clear positioning of DICOM in this respect.
Relationship to Other Standards:
· HL7 Clinical Document Architecture development needs to be coordinated with DICOM SR to ensure a complementary and compatible role.
· DICOM has type-A relation to ISO 215, and cooperates with ISO 215 on the standards for communication of biomedical diagnostics and therapeutic information in disciplines using digital images and associated data.
· For Security, the relation to HIPAA (United States), European Union Data Protection Directive, and HPB 517 in Japan.
· CEN TC251 on Medical Informatics Standards.
WG 11 (Display Function Standard)
Secretariat NEMA
Secretary Howard Clark, NEMA
Chairman Brad Hemminger, University of North Carolina
Date of Last Update: July 6, 2001
Scope:
To develop a display function standard and DICOM services related to image presentation objects.
Roadmap:
· Hanging Protocols ready for public comment summer of 2001.
· Interactive Collaboration approved as work item by early 2001. Interactive Collaboration ready for public comment by summer 2002.
· Several other topics may be addressed. Those that have the highest interest level are Advanced Presentation State, 3D presentation (in conjunction with WG 17 who is addressing 3D representation), and Structured Display, which is combining presentation state with structured reporting and potentially hanging protocols.
Short Term Goals:
· Bring Hanging Protocols (Supplement 58) to Public Comment.
· Prepare Interactive Collaboration (IC) for work item proposal.
· Work with WG 6 to revise Presentation LUT for hardcopy so that it is consistent with the rest of the standard (Softcopy Presentation LUT).
· Maintenance of existing two standards (Grayscale Standard Display Function, and Grayscale Softcopy Presentation State Storage).
Current Status:
· Grayscale Standard Display Function (GSDF), Supplement 28, Part 14 of DICOM 1998.
· CP-200: Table correction in DICOM Part 14; approved for Letter Ballot March 2000.
· Grayscale Softcopy Presentation State Storage, Supplement 33, September 1999, to be incorporated into DICOM 2000.
· Demonstration of Grayscale Softcopy Presentation State and Grayscale Standard Display Function at ECR 1999.
· Demonstration of Grayscale Softcopy Presentation State, Grayscale Standard Display Function and Presentation LUT (hardcopy consistency) at RSNA 1999.
· Public availability of demonstration and test software supporting Grayscale Softcopy Presentation State available in 1999 (release 1 in spring, release 2 at end of the year).
Current Work Items:
· Supplement 58: Hanging Protocols
Risks:
Short Term
· How does Hanging Protocols fit in the DICOM Information Model?
· Feasibility of finding language/representation for filtering/sorting decision making (will UML work?).
Roadmap
· Will Interactive Collaboration be perceived as being within the scope of DICOM?
· Requests for future work items will be dependent on the active participation of vendors and clinicians that perceive a need to expand the DICOM Standard in a specific area. Some items may require cooperation from other working groups, and/or a broadening of the scope of the Display working group.
Challenges and Opportunities:
Challenges
· Maintaining expertise, champions, vendor and clinical participation.
Opportunities
· Work with WG 14 (Security) for interactive collaboration (identification of users).
· Work with Structured Reporting for Structured Display.
· Work with WG17 on 3D presentation.
· Consolidate representation of Presentation LUT to consistent definition for both hardcopy and softcopy.
· Hanging Protocols can advance and unify softcopy reading paradigms.
· Grayscale Softcopy Presentation State demonstrations at IHE year 2 in RSNA 2000.
· Encourage use of Grayscale Softcopy Presentation State to be mandatory in IHE year 3.
Relationships to other Standards:
· GSDF refers to calibration (quality assurance and quality control) guidelines for electronic displays. Currently work is underway by AAPM Task Group 18 in this area, as well as potential work by IEC group 62B on electronic displays.
· UML (defacto standard) as language/expression syntax representation for Hanging Protocols.
WG 12 (Ultrasound)
Secretariat NEMA
Secretary Richard Eaton, NEMA
Chairman David Heaney, A.L.I. Technologies Inc.
Date of Last Update: November 30, 2000
Scope:
To develop extensions to DICOM that are specific to the needs of the ultrasound imaging community. This includes all aspects of ultrasound acquisition related workflow and generated data, such as single and multi-frame images, waveform data (doppler audio, phonocardiogram, voice, etc.), and measurements.
Roadmap:
Potential work items related to 3D-ultrasound acquisition and processing:
· This will be dependent on work completed by WG 17 that standardizes the approach for dealing with multi-dimensional image sets.
Potential work items related to JPEG 2000 compression:
· WG 12 will require support for the use of JPEG 2000 compression with multi-frame images. It is not yet clear if this will merely entail the same way of dealing with such data as is used for JPEG Lossy and JPEG Lossless compression in the DICOM Standard or if the JPEG 2000 actually includes a standard for Motion JPEG 2000 (there is no standard for Motion JPEG for example).
Short Term Goals:
· Support for ultrasound protocol data management in the DICOM Standard.
· Creating new templates and code Context Groups for ultrasound modality DICOM Structured Reporting.
· Adding the necessary measurement and observation codes required by ultrasound to the LOINC code database.
· Completion of Supplement 56: Ultrasound Waveform IOD.
· Investigation of the addition of MPEG compression to the DICOM Standard.
· Addition of DVD-RAM support to the Ultrasound Application Profile (for removable media).
Current Status:
· Support for ultrasound protocol data management in the DICOM Standard:
· This takes the form of two Change Proposals, CP 201 and CP230, related to protocol and ultrasound stage codes. These Change Proposals will soon both go to letter ballot.
· Creating new templates and code Context Groups for ultrasound modality DICOM Structured Reporting:
· Discussion papers and Structured Report examples for some specific types of ultrasound exams have been created. Specific issues have been identified and possible templates created.
· Adding the necessary measurement and observation codes required by ultrasound to the LOINC code database:
· We have had good co-operation from several professional associations in this endeavor. The main areas where we still need to compile and review terms are opthamology, and neurology.
· Completion of Supplement 56: Ultrasound Waveform IOD:
· A draft document of a possible new stand-alone IOD has been created and reviewed by WG 6.
· The waveform specific encoding is largely complete except for a finalization of Defined Terms for Channel Source and specification of the permitted Waveform Sample Interpretations (some subset of SB, SS, UB, MB, and AB).
· WG 12 members would prefer that the ultrasound waveform data could be included with the Ultrasound Image or Ultrasound Multi-frame Image Instances rather than having to be contained in separate, waveform only, Instances. A paper detailing both a justification for and the advantages of such an approach and will be presented at an upcoming WG 6 meeting.
· Investigation of addition of MPEG compression to the DICOM Standard:
· The first phase of our work is to determine whether MPEG really offers considerably greater compression ratios and/or performance for ultrasound cine than Lossy JPEG or JPEG 2000 compression. WG 12 members are concerned over the proliferation of compression types and want to make certain that MPEG support offers significant advantages before adding it to the DICOM Standard.
· Addition of DVD-RAM support to the Ultrasound Application Profile (for removable media):
· This is dependent on the completion and passing of Supplement 40, being generated by WG 5 (Exchange Media)
Current Work Items:
· Ultrasound protocol data management. This was originally to be Supplement 45 but now will be in the form of Change Proposals.
· Ultrasound modality reporting. WG 12 has a Work Item for Ultrasound Reporting. This will result in the creation of new SR Templates and Code Context Groups. There is currently no requirement for a new ultrasound specific SR IOD and SOP Class.
· Supplement 56: Ultrasound Waveform Data.
· Addition of MPEG compression to the DICOM Standard.
· Addition of DVD-RAM support to the Ultrasound Application Profile (for removable media). WG 12 does not have an official Work Item for DVD support as it will take the form of a Change Proposal once WG 5 has added DVD-RAM to the DICOM Standard.
Risks:
· The Change Proposal adding support for ultrasound protocol data management proposes new Context Groups for ultrasound protocol and stage codes. The terms and codes in these Groups are from SNOMED but not yet part of the SNOMED-DICOM licensing agreement. These term lists were originally compiled and submitted by a WG 12 member so the risk that they will not be free for our use is felt to be low.
· There are still large numbers of terms that are lacking in the LOINC database. Delays in completing the codification process will result in delays in implementation of ultrasound Structured Reports or compatibility issues resulting from the use of private codes in such reports.
· If we do decide to move forward with adding MPEG compression to the DICOM Standard there may be licensing and image quality issues (for example, with MPEG, quality degradation shows more variability between frames than with JPEG Lossy compression).
· Addition of DVD-RAM is dependent on progress by WG 5 and thus faces all the risks itemized by that Work Group. Adoption of both DVD-RAM and DVD-R could complicate site installations by possibly having two incompatible types of DVD media in use at a given site.
Challenges and Opportunities:
· Standardization of templates and codes for ultrasound Structured Reports offers greater opportunities for interchange of unambiguous coded measurements and observations. This will facilitate development and enhancement of data mining and research applications, as the data will no longer be interchanged only in text format.
· As detailed earlier there are still significant gaps in our coded terminology. It is proving difficult to find some of the required domain expertise and the work is very time consuming.
Relationships to other Standards:
· Use of LOINC for the codification of ultrasound measurement and observation terminology compiled by WG 12.
WG 13 (Visible Light) – This working group is not currently active.
Secretariat
Secretary
Co-Chairman
Co-Chairman
Date of Last Update: July 6, 2001
Scope:
To develop the Visible Light IODs to support Visible Light color images or monochrome images produced by endoscopes, microscopes, or photographic cameras.
WG 14 (Security)
Secretariat NEMA
Secretary Howard Clark, NEMA
Chairman Lawrence Tarbox, Siemens Medical Systems
Date of Last Update: July 6, 2001
Scope:
To develop extensions to DICOM with respect to security.
WG 15 (Mammography and CAD)
Secretariat American College of Radiology
Secretary Lynne Fairobent, ACR
Co-Chairman Dr. Carl Vyborny, ACR/LaGrange Memorial Hospital
Co-Chairman Janet E. Keyes, R2 Technology, Inc.
jkeyes@r2tech.com
Date of Last Update: June 15, 2001
Scope:
To develop extensions to DICOM to support digital mammography, and the structured reporting of Computer-Aided Detection / Diagnosis (CAD) results.
Roadmap:
The following are potential work items with respect to Structured Reporting:
· Reporting of Mammography CAD output across modalities: expansion beyond X-Ray projection into Ultrasound and/or MR breast imaging analysis.
· Reporting of CAD output results that are 3-Dimensional.
· Reporting of CAD output for additional anatomy.
The following are potential work items with respect to Image IODs:
· Addition of attributes or modules to describe DX/Mammography quality control and phantom images.
· Evaluation of the Ultrasound and MR Image IODs for completeness with respect to attributes specific to breast imaging.
· Addition of attributes or modules for energy subtraction in breast imaging.
· Use of CAD output to drive digital display devices.
Risks:
· Short term: Supplement 65, Chest CAD SR, is dependent on the clinical input received toward reaching consensus on a subset of chest radiography terminology to use in describing Chest CAD output results, and assignment of codes for that terminology.
· Short term: Patient Clinical History for Breast Imaging is dependent on the work of WG 8, Structured Reporting, for the definition of general and/or common templates that can be used by multiple working groups that are dealing with representation of patient clinical history.
· Roadmap: Requests for future work items will be dependent on the active participation of vendors and clinicians that perceive a need to expand the DICOM Standard in a specific area, and support of the Secretariat for those work items. Some items may require cooperation from other working groups.
Short Term Goals:
· Correction Proposal for TID 1400, Linear Measurement Template, to allow numeric measurements to be defined without requiring a reference to spatial coordinates, to Letter Ballot in June 2001.
· Supplement 65: Chest CAD SR SOP Class, to Public Comment in November 2001.
· General Mammography Report and Patient Clinical History for Breast Imaging Supplement(s), to Public Comment in January 2002.
· Add scheduling of CAD processing and the reporting of CAD output to the IHE Year 4 technical framework.
· Maintenance of the Digital Mammography X-Ray Image IOD and Mammography CAD SR IOD.
Current Status:
· The Digital Mammography working group was convened initially in February 1998, to ensure that Supplement 32: Digital X-Ray Supplement would meet the needs for the storage of digital mammography image objects in DICOM. The Secretariat is the American College of Radiology (ACR).
· Digital Mammography X-Ray Image Storage – For Presentation and For Processing SOP Classes in Supplement 32: Digital X-Ray Supplement, Final Text, 1 September 1998 (DICOM 1999).
· CP-193: Add Type 3 Partial View image attributes to the Mammography Image module, Final Text September 2000.
· Supplement 50: Mammography CAD SR SOP Class – an extension to DICOM to standardize the reporting of CAD results for mammography, using DICOM Structured Reporting; Final Text, May 2001.
· “Rejected for Quality Reasons” and “Quality Issue” included in Supplement 59, Key Object Selection Document, Final Text, May 2001 (in lieu of CP-192: Add Type 3 Rejected/Replacement image attributes to DX or Mammography Image module, withdrawn).
Current Work Items:
· Supplement 65: Chest CAD SR SOP Class, to standardize the reporting of CAD results for analysis of chest x-ray and/or CT images, using DICOM Structured Reporting; requested and approved April 2001.
· Definition of SR templates / SOP Class for a General Mammography report (generated by human and/or CAD), including patient clinical history and risk factors that may be used as input by CAD devices; requested and approved April 2001.
Challenges and Opportunities:
· The security of digital mammography image data and associated reports, to prohibit and/or at least recognize alteration, is a significant clinical and regulatory issue in the United States (HIPAA) and worldwide. Follow closely the progress of the Security working group and the NEMA MII Section, Privacy and Security Committee.
· Monitor future developments in CAD research, particularly those that make the technology actively interactive with radiologists.
Relationships to other Standards:
· Use of American College of Radiology (ACR) BI-RADSTM Third Edition, version 3.1 terminology as the basis of coded terminology for Structured Reporting for Mammography
· Use of the Mammography Quality Control Manual 1999, available from the American College of Radiology (ACR), as a basis of coded terminology for the reporting of mammography image quality characteristics
· Use of the Mammography Quality Standards Act (MQSA), a federal regulation of the United States government, as a basis of coded terminology for the reporting of mammography image quality characteristics
WG 16 (Magnetic Resonance)
Secretariat European DICOM Secretariat
Secretary Hermine Hekker, NNI
Co-Chairman Matthias Drobnitzky, Siemens, AG
matthias.drobnitzky@med.siemens.de
Co-Chairman Kees Verduin, Philips Medical Systems
Date of Last Update: November 12, 2000
Scope:
Modern MR pulse sequences can not be described sufficiently by the current standard. Furthermore, new applications such as functional MR and MR fluoroscopy, as well as the non-imaging application MR spectroscopy are not supported either. Especially the organization of increasingly large datasets as single frame objects is far from optimal and limitations of the existing definitions of spatial and temporal attributes are apparent. It has therefore been proposed that a new MR object be developed that contains a more extensive set of descriptive attributes and makes use of the multi-frame mechanisms and / or variants thereof as originally introduced by the nuclear medicine, ultrasound and x-ray angiography objects.
Roadmap:
WG16 first met in fall 1998. They followed a 3-month meeting schedule during 1999 and 2000. Requirements for the new MR IOD as well as for the anticipated multi-frame architecture were collected. Different variants thereof were discussed in depth between WG6 and WG16 until consensus was found. WG16 is aiming now for public comment phase to take place during 1st quarter of 2001. The working group activities and meeting schedule will then be intensified to reach letter ballot phase during 2nd quarter of 2001.
Short Term Goals:
- Work out pending actions aiming at completing the draft of supplement 49.
- Present supplement 49 to WG6 during their January 2001 meeting to get approval for public comment.
Current Status:
A draft of supplement 49 has been presented to WG6. It received approval of the overall content and architecture.
Current Work Items:
- Draft of supplement 49.
Risks:
- Comments during public comment phase which ask for major revisions of the current draft.
Challenges and Opportunities:
Challenges:
- MR applications are constantly being refined, new contrast generating mechanism are already foreseeable. The new MR IOD must be defined to be able to accommodate future MR techniques.
- Multi-frame techniques must be defined such that other modalities like CT can use the architecture.
Opportunities:
- Large groups of MR-users are organized in international scientific societies like ISMRM and ESMRMB or special interest groups like MRUI. Their feedback to WG16's work is appreciated.
Relationship to Other Standards:
- WG16 has no relationship with other standards developers.
WG 17 (3D)
Secretariat NEMA
Secretary Richard Eaton, NEMA
Chairman Doug Sluis, ATL
Date of Last
Update: August
10, 2000
Scope:
To extend the DICOM Standard with respect to 3D and other multi-dimensional data sets. WG17 is extending DICOM to represent data types greater than two dimensions. In existing DICOM the atomic unit of image data is the 2D frame. Some emerging acquisition modalities (as well as 3D visualization and quantitative analysis applications) are volumetric-based. These need a volumetric friendly representation. Additionally, new diagnostic modalities may generate data with multiple components. Existing DICOM does not support this.
Representative applications include:
· Visualization of volumetric and cine volumetric
· Diagnostic quantitative and assisted detection using automated segmentation and classification
· Treatment planning
· Intra-operative applications such as Image Guided Therapy
Roadmap:
· WG17 is seeking consensus with WG6 on the proposed approach. In the meantime, WG17 is defining the approach in more detail, prototyping modules and creating use cases for: representation of
· Spatial fiducials (landmarks) to enable registration between datasets or to a real world coordinates
· Spatial transformations to describe the registration between data sets
· Multi-component data
· Derived data types such as segmentations
· Get official Work Item for the Supplement
· Create a public draft Supplement for early 200
· Longer term, WG17 will collaborate with WG11 to define presentation extensions to add new Supplements for image compression, new coordinate systems, and others not yet identified.
Short Term Goals:
· Reach agreement with WG6 on the general approach
· Request work items
Current Status:
· Requirements document is up to date
· Draft modules are in preparation for input to Supplement
· Performed a feasibility evaluation the Multi-Frame Sequence Encoding approach and found it to be lacking for WG17's needs
Current Work Items:
There is no formal work item at this time. Once consensus with WG6 is achieved, WG17 will likely request work items for:
· Frame of Reference Transformation Supplement. It is a goal that this supplement can extend both existing IOD's as well as new IOD's abased on the multi-dimensional framework
· Spatial Fiducials Supplement. It is a goal that this supplement can extend both existing IOD's as well as new IOD's abased on the multi-dimensional framework
· Multi-Dimensional Supplement. This supplement will provide for data sets that use any extend in any or all spatio-temporal dimensions, as well as multi-component data types. This will define new data types such as segmented
Risks:
It is imperative that WG6 and WG17 resolve issues and achieve global DICOM consensus.
Challenges and Opportunities:
· Provide a sufficiently powerful and general approach to satisfy anticipated applications in relevant clinical domains and modalities, while leveraging existing DICOM as much as possible.
· Leverage other relevant standards
· Reduce the complexity of expression of the Multi-Dimensional Supplements to ease adoption and implementation
Relationships to other Standards:
· WG17 has no relationship with other standards developers. Standards activities of potential relevance include ISO JTC1, SC29, WG1, JPEG2000. Proposed extensions for 3D transforms are relevant and of interest.
· WG17 will evaluate relevant standards (particularly in the area of presentation) to be as consistent as possible with industry familiar standards
WG 18 (Clinical Trials and Education)
Secretariat National Cancer Institute
Secretary Edward Staab, NIH
Co-Chairman Curtis
Langlotz, University of Pennsylvania
Co-Chairman Andrew
Kraus, BioCor
Date of Last Update: November 20, 2000
Scope:
To extend the DICOM Standard with respect to clinical trials information and the storage of images for educational purposes.
DICOM Working Group 18 was first convened in 1999 to address issues unique to the use of images in clinical trials and education. The working group elected to focus first on clinical trials before devoting significant time to education and imaging teaching files.
In its initial meetings, the Working Group determined that there are several shortcomings of the current DICOM standard when it is used in the context of clinical trials. First, there are no standard methods for “scrubbing” patient-identifying information from the DICOM header while retaining a identifiers to reestablish the patient’s identity for audit purposes. Second, a variety of clinical trials attributes are missing, including the ability to capture a unique subject identifier, the protocol for which an image was obtained, and the sponsor of the clinical trial. Third, even when some of this information is stored in optional fields, the storage arrangement varies according to vendor and frequently cannot be displayed on off-the-shelf workstations. Fourth, certain common imaging parameters that are essential for the conduct of clinical trials, such as MR echo time and repetition time, are not stored in consistent locations.
Roadmap:
The Working Group believes that the establishment of standard optional attributes for clinical trials information would assist organizations that conduct clinical trials in which images are a key component. The Working Group hopes that the establishment of DICOM standards for clinical trials information would lead to an increasing role for DICOM in submissions to the Food and Drug Administration and the National Cancer Institute, as well as other organizations that support or regulate research on medical imaging.
Short Term Goals:
The Working Group has determined that it is desirable to add optional attributes to existing DICOM Image Storage Information Object Definitions (IODs) that will allow standard locations for certain basic information for clinical trials, as well as certain modality specific attributes (e.g., MR TR/TE) that are commonly encountered in clinical trials images. A work item has been approved for that purpose.
Current Work Items:
The DICOM Clinical Trials WG 18 has determined that it is desirable to add optional attributes to existing DICOM Image Storage IODs. There are two groups of attributes missing:
- Those relating to clinical trial procedures, such as identification of client, clinical protocol, site number, randomization, etc.
- Technique related attributes (e.g. for spiral CT, calibration of distance on scanned film).
It is proposed to create a supplement describing the additional attributes and the information model supporting them.
Challenges and Opportunities:
·
Improve the utility of the DICOM standard for clinical
trials.
· Broaden the participating members of the working group among workstation vendors and regulatory agencies.
·
Reach out to other industry groups such as research
quality assurance firms and software engineering organizations.
·
Improve cross-fertilization among our group and other
DICOM Working Groups, including the Digital Mammography and Security working
groups.
WG 19 (Dermatologic Standards) – This working group is not currently active.
Secretariat American Academy of Dermatology
Secretary
Chairman
Date of Last Update: September 1, 2000
Scope:
To extend the DICOM Standard with respect to standards for dermatologic imaging and digital communications.
Roadmap:
The long range goals include a more in depth analysis of other forms of cutaneous imaging such as epiluminescence microscopy and confocal microscopy to see if the current standard is applicable or any additional work would need to be done.
Short Term Goals:
· Engage vendors to participate in the creation of a DICOM capture/viewer module for dermatologic images.
· Develop consensus in the global dermatologic community around structured vocabulary and its standardization.
Current Status:
An in-depth review of supplement 15 as it pertains to cutaneous color images has been completed. The consensus of the group is that supplement 15, as currently written, meets the needs of color cutaneous imaging.
Current Work Items:
There is no formal work item at this time.
Risks:
The main risk at this time is lack of vendor interest. The skin imaging market is still a very small one and most vendors who are involved sell non-specialized products to this market as part of other horizontal product strategies. The cost to differentiate a cutaneous imaging product line may not be of interest for some time. A second risk is the ambivalence of the American Academy of Dermatology to this activity. A third risk involves the building of consensus around a dermatologic coded vocabulary. Any time consensus is viewed as necessary; there is risk that it cannot be achieved.
Challenges and Opportunities:
These are reviewed in the items above.
Relationships to other Standards:
The work of this group would be of interest to those standards organizations focused on still cutaneous images (e.g., JPEG) and those involved in structured vocabulary (e.g., SNOMED)
WG 20 (Integration of Imaging and Information Systems)
Secretariat NEMA
Secretary Howard Clark, NEMA
Chair Fred Behlen, ACR
Date of Last Update: June 26, 2001
Scope:
To develop DICOM and HL7 standards for image-related information for areas where the consistent use of HL7 and DICOM is of prime concern, and the coordination and mutual education and understanding between the HL7 and DICOM organizations and their technical committees/working groups.
Roadmap:
· Contribute to HL7 Reference Information Model (RIM) any additional classes or attributes needed for representing DICOM information model
· Work with Structured Document Technical Committee to develop document description for SR, resulting in the mapping o f DICOM SR objects into CDA Level 3 documents.
· Develop messages supporting Imaging Integration
Short Term Goals:
· Modeling DICOM concepts in the HL7 Reference Information Model
· Participation in HL7 Version 3 development to maximize compatibility between HL7 and DICOM
· Extensions to HL7 Version 2.5 order messages to serve the needs identified in the IHE program
Current Status:
· Version 2 Orders message extension pending final committee approval, will go into 2.5 ballot to be released early 2002
· CDA Level 3 Committee level ballot release expected February 2002
Current Work Items:
· No current DICOM work items
· HL7 activities:
· Imaging Integration Segment for Version 2.5 order message
· RIM Harmonization proposals
Risks:
· Linking goals to related efforts in HL7 exposes us to delays over which we may have limited control
· A risk for DICOM is that non-DICOM visible light imaging in HL7 may compete with DICOM VL
Challenges and Opportunities:
· A continued challenge is that most of the participants are more experienced in DICOM than in HL7. We need to find ways to encourage participation from information system vendors.
· Opportunity exists in HL7’s beginning a Templates SIG, and it will be important to coordinate HL7 and DICOM template activities. WG20 co-chair Martin Kernberg is also co-chair of the Templates SIG.
Relationship to other Standards:
· Primary relationship as a joint working group with HL7. WG20 has the same co-chairs and membership as HL7’s Imaging Integration SIG.
· At its HL7 meeting venue, the group has regular informal contact with members of international standards groups such as ISO TC215, CEN, GEHR, and HL7 international affiliates.
WG 21 (Computed Tomography)
Secretariat NEMA
Secretary Howard Clark, NEMA
Co-Chairman Stephen Metz, GE Medical Systems
Co-Chairman Emil Wirsz, Siemens Medical Systems
Date of Last Update: July 6, 2001
Scope:
To develop an extended CT image object to support the many technological and clinical
advances in Computed Tomography. In
particular the increase in the number of slices in an exam and the real-time
capabilities of CT technology makes it desirable to create a new DICOM object
with a multi-frame capability.
Consistency with the MR Multi-Frame IOD under specification is important
as many workstations support both CT and MR applications. Consistency with the new XA Multi-frame IOD
is also important so that Cardiology or Angiography applications can benefit
from both CT and X-ray acquisitions.
Roadmap:
· The Working Group is in the process of establishing its roadmap and developing the requirements for an enhanced CT IOD.
Short Term Goals:
· Completion of a supplement specifying a new CT Multi-frame Image Object (Supplement 58)
· Maintenance of the CT Image IOD.
Current Status:
· The DICOM Committee approved this new working group in June 2000.
· The first meeting happened in September 2000. During this kick-off meeting, a joint working session was held with the MR WG 16 to ensure consistency of definition between the MR multi-frame and the CT multi-frame image objects.
Current Work Items:
· Definition of a new CT Multi-frame IOD and its associated Storage SOP Class.
Challenges and Opportunities:
· Unless an XA/RF Second Generation Multi-frame IOD definition is started, the opportunity to define a consistent multi-frame for MR, CT and X-Ray may be missed.
· Ensure rapid progress to not slow down the progress of the MR Working Group.