DICOM Working Group 10 London, 23 June 2003 Integrating Imaging and Reporting using DICOM SR and HL7

1
DICOM Working Group 10London, 23 June
2003Integrating Imaging and Reporting using
DICOM SR and HL7 CDA

• Fred M. Behlen, Ph.D.
• Co-Chair, DICOM WG20 / HL7 IISIGMember, HL7
  Structured Document TC

LAItechnology
Longitudinal Application Integration Solutions
for Health Records
2
Use Cases for CDA inDICOM Application Domains

• Report created in DICOM SR, transformed to CDA
  for export
• Report created in CDA, including image references
  and annotation
• DICOM evidence production requires input from
  external CDA documents
• Imaging application needs to present rendered CDA
  content

3
1. Report created in SR, trans-formed to CDA for
export

• SR Reporting application tightly integrated with
  image viewing and annotation application
• CDA document references SR source document
• Need
• SR-to-CDA standards and tools
• Constraints on SR for reliable transformation
• Trial transformations of existing SR Templates
• Rules defining boundaries for new templates
• Robust CDA reference pointers to DICOM objects
  (WADO DIMSE access)

4
2. Report created in CDA

• Image viewing and CDA reporting may be different
  applications, on the same or different platforms
• Reporting including image references and
  annotation is done in CDA document
• Reporting application may require access to DICOM
  SR evidence documents
• Potential encapsulation of CDA in DICOM for
  management with other DICOM objects?
• Need
• Messaging between image viewing and CDA reporting
  application
• Robust CDA reference pointers to DICOM objects
  (WADO DIMSE access)

5
3. Import CDA data for DICOM evidence production

• CDA Structured content needs to be imported into
  DICOM application
• Requires a query and retrieve mechanism from
  DICOM appli-cation to CDA repository (crosses
  DICOM/HL7 boundary)
• May overlap with Relevant Patient Information
  Query
• CDA content may include image references
• Need
• May not require additional standards work if RPIQ
  is used
• If RPIQ is not used, then need to define Q/R
  mechanism and possible encapsulation in DICOM
  environment
• Even if RPIQ is used, Query/display may be
  required
• Need to define templates for specific content
  extracts from CDA

6
4. Display rendered CDA

• CDA content not required in DICOM application
• Requires a query/display mechanism from DICOM
  application to CDA repository
• CDA content may include image references
• Need
• Query facilities already planned as IHE CDA
  Query/Display
• Display may need to extract DICOM image reference
  and annotation from CDA document for rendering in
  diagnostic quality display

7
Use Cases for CDA

• Report created in DICOM SR, transformed to CDA
  for export? Subspecialty domains only
• Report created in CDA, including image references
  and annotation
• DICOM evidence production requires input from
  external CDA documents? May be served by RPIQ
• Imaging application needs to present rendered CDA
  content ? No additional standards work required

8
CDA Reporting Integration

• Create authenticated reports directly in target
  format
• CDA Release 2 (first committee ballot August
  2003) has equivalent of DICOM SCOORD and image
  referencing
• Image viewing and reporting done in different
  appli-cations, on same or different (adjacent)
  platforms
• Network communications model serves both cases

9
CDA Reporting Integration
Communications over TCP/IP(to server if
Web-based)
Image Viewing Application
Reporting Application
Measurements, Annotation
Display control optional (User, Patient and
Exam context)
10
CDA Reporting Integration
Communications over TCP/IP(to server if
Web-based)
Image Viewing Application
Reporting Application
Measurements, Annotation
Display control optional (User, Patient and
Exam context)

• Display control.
• Use CCOW?
• DICOM Normalized Services?
• OLE automation?
• Special-purpose XML messaging?

• Measurements and Annotation
• DICOM Application Event Notification Service
  (Supp. 66)?
• HL7 V.3 Messaging?
• Special-purpose XML messages?

11
Display control optional

• CCOW
• Expensive
• High entry level
• DICOM Normalized Services
• New standards development
• Costly implementation
• Requires reporting vendor to adopt and support
  DICOM protocol stack and tools
• OLE Automation
• Microsoft Windows only
• May not work / security problems over network
• Special-purpose XML messaging?
• New to DICOM, but IHE audit trail uses similar
  approach
• Uses same connection as XML measurement/annotation

12
Measurements Annotation

• DICOM Application Event Notification Service
  (Supp. 66)?
• Annotation in SR document fragments
• Costly implementation on reporting system end
• Requires reporting vendor to adopt and support
  DICOM protocol stack and tools
• HL7 V.3 Messages?
• Standards development required, not really HL7
  application domain
• Special-purpose XML messaging?
• Annotation in CDA document fragments
• New to DICOM, but IHE audit trail uses similar
  approach
• Uses same connection as XML measurement/annotation

13
Special-purpose XMLmessaging?

• Point-to-point TCP/IP socket connection
• Could be secured using TLS Record Layer Protocol
  if desired
• W3C XML Schema validation of messages
• Single Schema for messages in each direction
• Event notification function only, minimal
  protocol overhead
• Instance UID allows receiver to ignore duplicate
  sends, but otherwise no flow control

14
Conclusion Viable Protocols

• DICOM Normalized services
• Standards exist (Supp. 66) for event logging
• Standards development
• SR root templates for annotation measurements
• SR-to-CDA mapping for annotation measurements
• CDA Diagnostic Imaging Report document
  specification
• Special-purpose XML protocol
• Standards development
• XML message schemas for annotation measurements
• Socket transport specification
• CDA Diagnostic Imaging Report document
  specification
• ? More work for standards developers, less work
  for implementers

15
Open Issues

• If XML protocol, where would it go in the
  Standard?
• A new Part?
• An Annex?
• Where would the CDA Imaging Report document
  profile go?
• The IHE Technical Framework?
• An HL7 Informative Document?
• To become a balloted Template when (someday) HL7
  Templates are available?
• A DICOM standard?

16
A Possible Schedule
17
Accelerated Schedule