Transcript DICOM conference

2016 DICOM Education Day – September 6, 2016
Affiliated Zhongshan Hospital of Dalian University,
Dalian, China
DICOM Process
International, Universal and Open
Stability and Evolution
Kevin O’Donnell
Toshiba Medical Systems
Sr. R&D Mgr., Connectivity, Standards & Integration
Co-chair DICOM WG10 – Strategic
Past Co-chair DICOM Standards Committee
The DICOM Standard
• Administered and published by
‒ National Electrical Manufacturers Association
and it’s medical imaging division
‒ Medical Imaging Technology Alliance
• Intellectual property
‒ DICOM trademark and copyright is held by NEMA
‒ Developed using NEMA Codes and Standards process
‒ No license required to use the DICOM Standard in products
• http://dicom.nema.org
‒ Download free electronic copies of the standard
 All 20 parts are available in PDF, Word, HTML, and XML format
 Paper copies are available for purchase
‒ Plans and activities are publicly posted
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Universal Adoption
• DICOM is the International Standard for Medical Imaging
and related information (NEMA PS3, ISO 12052)
‒ One of the most widely deployed healthcare
messaging standards in world
> Billions of DICOM images
‒ Digital imaging devices in Radiology use DICOM :
> 90%
‒ Large hospitals (worldwide) use DICOM-based PACS :
> 90%
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International Standard
• It’s DICOM
‒ no Japanese DICOM, German DICOM, Spanish DICOM, …
• One standard; not different national standards
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Data encoding is mostly language independent
DICOM features handle Japanese & German & Spanish, …
Character encoding is selectable (GB18030, GB2312, UTF-8, …)
Name representations: alphabetic, ideographic and/or phonetic
• Global compatibility of products; of patient data
‒ Supports languages and needs of users worldwide
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International Organization
• It’s DICOM
‒ no DICOM-USA, DICOM-France, DICOM-China, …
• One Organization; by topic not by geography
‒ DSC & Working Groups are international
‒ Members come from everywhere
• Open to direct participation by stakeholders
‒ American members include ACR, FDA, NCI, RSNA, …
‒ Japanese members include JIRA, JAHIS, JSRT, …
‒ Stakeholders participate by:
 Promoting the use of DICOM and educating users
 Identifying issues and suggesting solutions
 Proposing new extensions & Working on the Standard
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Working Groups
• Modality, clinical domain, or technology expert teams
• Assigned to develop Supplements or Change Proposals
WG-01: Cardiac and Vascular Information
WG-02: Projection Radiography/Angiography
WG-03: Nuclear Medicine
WG-04: Compression
WG-05: Exchange Media
WG-06: Base Standard
WG-07: Radiotherapy
WG-08: Structured Reporting
WG-09: Ophthalmology
WG-10: Strategic Advisory
WG-11: Display Function Standard
WG-12: Ultrasound
WG-13: Visible Light
WG-14: Security
WG-15: Digital Mammography and CAD
WG-16: Magnetic Resonance
WG-17: 3D
WG-18: Clinical Trials and Education
WG-19: Dermatology
WG-20: Integration of Imaging and Info Systems
WG-21: Computed Tomography
WG-22: Dentistry
WG-23: Application Hosting
WG-24: Surgery
WG-25: Veterinary Medicine
WG-26: Pathology
WG-27: Web Technology for DICOM
WG-28: Physics
WG-29: Education, Communication & Outreach
WG-30: Small Animal Imaging
WG-31: Conformance
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DICOM is not Static
• DICOM first published in 1993
• Extended regularly to meet the
expanding needs of Medical Imaging:
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Multi-energy CT
3D Ultrasound
Web-based PACS
USB Memory Sticks
Clinical Measurements
Radiation Dose Reporting
Image Registration & Segmentation
Computer Aided Detection/Diagnosis
and Many, Many More . . .
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DICOM Change Process
• Supplements for major changes
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New object types, new services, new compression schemes
About 10 / year
Developed by Working Groups
Require Work Item approved by DICOM Standards Committee
• Change Proposals for minor corrections & clarifications
‒ About 100 / year
‒ Anyone can submit
‒ Backward Compatibility: Avoid changes that break existing
implementations
• Continuous maintenance process
‒ WG-06 (“Architecture Review Board”) meets five times per year
‒ All documents published for open Public Comment;
later formal vote by Letter Ballot
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Recent Supplements
• DICOMweb: RESTful Web Services
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WADO, STOW, QIDO, UPS, Rendering
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Radiology Reports using HL7 CDA
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Radiation Dose
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X-ray, Radiopharmaceutical
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Breast Tomosynthesis
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Magnetic Resonance analytics
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Ophthalmology
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Later Today
Various devices
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Work in Progress
• CT Protocol Storage
- (Sup121)
• Multi-Energy CT Storage
- (Sup188)
• Protocol Approval
- (Sup192)
• Simplified Echo SR
- (Sup169)
• Patient Dose SR
- (Sup191)
• Contrast Injection SR
- (Sup164)
• Web Services Redoc
- (Part 18)
• HEVC H265 Video Coding
- (Sup195)
• Curved MPR Presentation State
- (Sup182)
• Volume Rendering Presentation State
- (Sup190)
• Second Generation Radiotherapy Prescription
- (Sup147)
Maintaining Stability
• No “Versioning”
‒ It’s just “DICOM”
Not “DICOM 3.1”, “3.2”, “2015b”, etc.
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DICOM SOP Class
Service + Object = Service Object Pair
(Storage + MR Image = MR Image Storage)
MR Image Storage SOP Class
SCU
SCP
• SCU – Service Class User
‒ the system that uses the service (client)
• SCP – Service Class Provider
‒ the system that provides the service (server)
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Other Examples
SOP Class services and objects
‒ Store a CT image
‒ Store an XR image
‒ Find the studies for a patient
‒ Find the worklist for a modality
‒ Move a set of images
‒ Create an image print job
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Maintaining Stability
• No “Versioning”
‒ It’s just “DICOM”
Not “DICOM 3.1”, “3.2”, “2015b”, etc.
• DICOM evolves by adding new “SOP Classes”
‒ New SOP Classes are added
‒ Old SOP Classes don’t “break”
‒ Most applications continue to support older SOP Classes
when supporting new ones
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Conformance vs Publication
• DICOM Conformance is to SOP Classes
– not to a version of the Standard
• New DICOM editions are published (e.g. 2016c)
‒ SOP Classes are added but not changed incompatibly
• Each SOP Class is stable
‒ forward and backward compatible across all editions
‒ any data elements added are optional
• Products conforming to the same SOP Class interoperate
‒ Humans compare DICOM Conformance Statements (DCS)
‒ Machines do Association Negotiation
Information Model Stability
• New SOP Classes and
Information Objects conform to
existing information/real-world
model
• Allows reuse in implementation
• Leverage standard modules in toolkits
• PACS can handle new objects with
minimal change
• Avoid temptation to “improve”
DICOM Overview
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Stability and Maintenance
• Rule #1: Don’t break existing implementations
In existing SOP Classes:
‒ Clarify but don’t change meaning
‒ Add new codes, attributes, or behaviors BUT
products are not required to support and
can safely ignore them.
‒ Exception: fix something that is already broken
• The Caveat
‒ Vendors are still responsible to monitor CPs
and fix their products when they are deficient
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Translations of DICOM
• Translation is beneficial
‒ DICOM is a large, complex technical document
‒ Help implementers & users to understand & adopt
• Deviations in translation text are unavoidable
‒ Even DICOM Work Groups extensively debate text; any
translator will unintentionally miss details of meaning
‒ Concepts may have no easy translation
‒ Translations necessarily lag behind the current continuous
maintenance normative text
‒ DICOM Std Cmte does not validate or approve translations
• Deviations bring confusion and non-conformities
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DICOM Policy on Translation
• One normative global specification of DICOM
‒ The English language edition produced by the
DICOM Standards Committee is normative
‒ Assures world-wide clinical interoperability for
patient safety
‒ Enables global market for conformant equipment
• Translations are non-normative
‒ Standard disclaimer text – “Best effort”
discrepancies from normative text may exist
‒ Where discrepancies exist, refer to the original text
• May publish translations on DICOM web site
‒ Possible hyperlinks to normative text
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Translation Disclaimer
…
The normative DICOM Standard is published in
English, and is available free on the official website at
http://dicom.nema.org/standard.html.
…
In the event of any difference between this translation
and the DICOM Standard published in English by
NEMA, the English version is normative and takes
precedence.
…
- http://dicom.nema.org/translation.html
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Licensing
• NEMA holds the copyright
• Must obtain permission to translate / publish
• Preconditions:
‒ Non-normative
‒ Include standard disclaimer cover page in English and
the translated language in the publication
• Licenses are non-exclusive
‒ Previous licenses granted to organizations in Japan
and China
‒ Other organizations working on Chinese translation
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XML / Web publication
• DICOM Standard is maintained in DocBook XML and
published free on the Web in multiple formats:
‒ PDF - the official version
‒ XML - for automatic update of tools
‒ HTML - for easy use with hyperlinks to references
‒ MS Word - for extraction into project
documentation
• Re-published several times per year to incorporate all
approved Supplements and Change Proposals
•
http://dicom.nema.org/standard.html
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Internationalization (i18n) and
Localization (L10n)
• DICOM is an internationalized standard
• DICOM supports localization
‒ Address national/local health and workflow policies
without deviating from the Standard
‒ Locally specify code sets (e.g., procedure codes)
‒ Locally profile data element usage (optional -> required)
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Meeting local needs
Address language, culture, regulation, local medical and
administrative practices through two mechanisms:
1. Maintenance pathway
‒ Use the DICOM Maintenance process to update / extend
DICOM directly
‒ Ensures all relevant parts of DICOM are addressed
‒ Avoids conflict with future updates to DICOM
2. Profiling pathway
‒ Add supplemental requirements without conflicting
(“Yes, and ALSO…”)
‒ Separate Document from referenced Standard, managed /
published by the profiling authority
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i18n Maintenance
• When gaps identified, address as maintenance
‒ Supplement 9 – Multi-byte Character Sets
‒ CP1234 – Change Proposal to support GBK
• WG-6 ensures appropriate use of the Standard
‒ Make sure nothing breaks…
• Maintenance makes feature available globally;
encourages broad adoption
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Participate !
• DICOM invites new members
& contributors
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Application process
Patent disclosure policy
dicom.nema.org
[email protected]
• Great opportunity to learn
• Great opportunity to contribute
Industry-wide Collaboration
DICOM Standards Committee
“the Board of Directors”
‒ 19 clinical user organization members
 radiology, cardiology, dentistry, pathology, ophthalmology,
informatics, …
‒ 27 manufacturer members
‒ 11 associations and governmental bodies
 from Brazil, Canada, China, Europe, India, Japan, USA, …
Author Contacts
• Kevin O’Donnell
‒ [email protected]
‒ Toshiba Medical Research Institute – USA, Inc.
706 Deerpath Drive,
Vernon Hills, IL
USA 60061
Thank you for your attention!
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