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DICOM Conformance Statement (DCS) A Proven Power within DICOM. Dwight A. Simon, Medical Standards Director & Senior Integration Specialist Merge eFilm. A 10 year Proven track record of Power. It is Required It is a Public document
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DICOM Conformance Statement(DCS)A Proven Power within DICOM Dwight A. Simon, Medical Standards Director & Senior Integration Specialist Merge eFilm
A 10 year Proven track record of Power • It is Required • It is a Public document • It describes the DICOM Features / Functions implemented in a Product • It allows connectivity comparisons • It defines the information that is required to perform specific functions
Content of DCS Using 2003 Publication of Std • A brief introduction that is specified in general terms • A simple data flow diagram and description • The functional definition of each DICOM feature • More detail on specifics later • How this product communicates to another product
Content of DCS Using 2003 Std continued • Specification of any enhancements or changes to standard DICOM features • A list of configurable parameters • A list of character sets that are supported (i.e., Japanese or French) • Any codes and controlled terminology • A specification of all DICOM security features
Functional Definitions … more detail • Specification of each feature/function within the application • Utilizes specific terminology of DICOM • Benefit - defined in an unambiguous way • Disadvantage - must understand the terminology in order to get all the information one needs to: • Understand the products DICOM features • Compare this DICOM product with another
Almost Everyone follows the Templates from the Standard for writing a DCS • The common format is a huge benefit • Easy to find information, because always in same place • Easy to compare one DICOM product with another
Who has ability to use this information with a high degree of understanding? • Those that have taken DICOM training • Those that have read and understood the DICOM Standard • Unfortunately, the common healthcare user who does not have this background can probably only understand less than 40% of the information in the DCS
Presentation Context Table - Accepted Abstract Syntax Transfer Syntax Role Expanded Name UID Name List UID List Negotiation Study Root 1.2.840.10008.5.1.4.1. Implicit VR LE 1.2.840.10008.1.2 SCP None Query/Retrieve - FIND 2.2.1 Study Root 1.2.840.10008.5.1.4.1. Implicit VR LE 1.2.840.10008.1.2 SCP None Query/Retrieve - 2.2.2 MOVE Verification 1.2.840.10008.1.1 Implicit VR LE 1.2.840.10008.1.2 SCP None Presentation Context Tables Association Initiation Presentation Context Table - Proposed Abstract Syntax Transfer Syntax Role Expanded Name UID Name List UID List Negotiation X-ray RF Image 1.2.840.10008.5.1.4.1.1.12.2 Implicit VR LE 1.2.840.10008.1.2 SCU None Storage JPEG-14 1.2.840.10008.1.2.4.70 Lossless (70) Secondary 1.2.840.10008.5.1.4.1.1.7 Implicit VR LE 1.2.840.10008.1.2 SCU None Capture Image Explicit VR BE 1.2.840.10008.1.2.2 Storage Association Acceptance
Other Likely Unknown Terms • AE Specification • Application Entity Title • Application Profile • SOP Class • SOP Instance • Standard Extended SOP Class • Unique Identifier (UID)
After 10 yearsDICOM Conformance Statement has become even more Powerful • It includes an enhanced template • It has a wider range of examples that deal with the majority of possible DICOM features • It has grown from 50 pages to over 330 pages
Enhancement is called Supplement 64 • Already balloted and approved to become part of the DICOM Standard • Minor corrections and editing still to be done by Working Group 6 prior to making it a final document
Supplement 64 Enhancements (Sup64) • Will benefit the non-DICOM literate user directly • Will enable the DICOM literate user to more easily find and compare DICOM features • Will be additive to most of what is in the current 2003 publication
Sup64 – New Additions • DICOM Conformance Statement Overview • Includes a description of the implementation in "layman's terms“ • Requires that the tables for both Networking and Media Storage • List all used DICOM features (SOP Classes) • List be organized and grouped by categories
Sup64 – New Additions … continued • Requires a Table of Contents (some vendors already do this) • New "Introduction" section • The "Definitions, Terms and Abbreviations" item will be one key addition for the non-DICOM literate • If vendors do a good job with this item, then these users should be able to have an 80% or higher understanding of the DCS
Sup64 – New Additions … continued • Enhancements to "Sequencing of Real-World Activities" • Defines interactions between this product’s various DICOM connections and other products • It is strongly recommended to incorporate UML Sequence Diagrams • Sequence diagrams emphasize the sequence of the DICOM messages between two products • Even without a formal understanding of the Unified Modeling Language (UML) the average user should be able to interpret the diagrams
UML Sequencing Diagram StorageApplication Image / Info Manager 1. Open Association 2. C-STORE (CT Image) [1 to N images to be sent] 3. C-STORE (GSPS) [1 to N grayscale image consistency information sets to be sent] 4. N-ACTION (Storage Commitment Request for Images & GSPS) [Are they reliably stored] 5. N-EVENT-REPORT (Storage Commitment Response) [Each are or are not reliably stored] 6. Close Association
Sup64 – New Additions … continued • The "Configuration" section has also been enhanced. • Requires a much more definitive description of the configurable parameters that the application will utilize when it is running • The parameters refer to application name(s), networking relationships, remote application connectivity, node level security, etc. • There is a recommended set of operational parameters that are required to be represented
Sup64 – New Additions … continued • The powerful "Annexes" section helps define some of the operational aspects of the product • Within the Annexes one must describe • the data that is created, • put in the DICOM message and • sent to another product.
Sup64 – New Additions … continued • Within the Annexes" each piece of information (called an attribute) must be specified • by name and • DICOM identifier (called attribute tag), • range of values that might be present • type of value • person name • date • time • floating point double precision number • integer number
Sup64 – New Additions … continued • Within the Annexes each attribute must be defined • whether it will or will not exist within a DICOM message and under what conditions it will exist • If its value is present, then from where will it come • from user input • be generated automatically • come from functional information like a work list • be a configurable parameter.
Sup64 – New Additions … continued • other important items within "Annexes" • specification of attributes that are required • mapping of attributes between different information sets • HL7 mapped into a DICOM work list • DICOM work list mapped into a CT image • specify whether key attributes are allowed to be modified • patient name • patient identifier • study instance UID
Sup64 – New Additions … continued • A data dictionary of all private attributes • The support of coded terminology and/or templates, if utilized • The support for "Grayscale Image Consistency", if applicable • A definition of any enhancements or changes to standard DICOM features that have been implemented, including feature specialization or new private features • All private encoding of information that is support, if applicable
Sup64 – New Additions … continued • Many informative sections in PS3.2 • specifically to give examples of DICOM Conformance Statements for various types of products • a huge benefit to both the vendors and the users • for the vendors, they are used as a guideline for interpreting the DCS template for a specific kind of product • for the user, it will insure that multiple vendors with similar products will have DCSes that look alike.
DCS Examples available in Sup64 • A DICOM modality that has connectivity to an archive, a workflow manager and a print server, along with have the capability to create a DICOM generic CD-Rs • A product that interfaces to a Radiology Information System via DICOM • A DICOM image viewer that can handle a wide range of modality images, including radiation therapy planning information. It also can query and retrieve information from a remote application and can read both DICOM generic CD-R and DVD-RAM • A DICOM print server • A DICOM query/retrieve server
DICOM would truly only have Half the Power it currently has without the DICOM Conformance Statement!
With the Enhanced DICOM Conformance Statement • ability to better understand how products connect to each other via DICOM • what information they communicate and under what conditions • what information must be received for the application to function properly • how parameters must be configured to make the application function in specific ways • a formal way to describe the sequencing of messages between DICOM applications