XDS-I Registry Metadata Extensions - Detailed Proposal
1. Proposed Workitem: XDS-I Registry Metadata Extensions - Detailed Proposal
- Proposal Editor: David Heaney
- Editor: David Heaney
- Domain: Radiology
Summary
A lot of XDS Affinity Domains are extending the XDS Registry metadata to include certain radiology specific information: Study Instance UID, Accession Number, etc. Currently this is being done in a purely customized manner so for example, two Registries that have added support for Study Instance UIDs will not have done it in the exact same way.
This work item proposes that IHE Radiology define a standardized way of extending XDS metadata. For example, it could be specified that the DICOM attribute Tag number shall be used in a specific way if a DICOM attribute is to be used in the metadata.
To a large extent this work item will be dependent upon work done in IHE ITI as the ITI Technical Committee needs to define the generalized way in which XDS metadata can be extended. IHE ITI has indicated that they have already begun work on this effort. There is still work that IHE Radiology could do while waiting for the output of ITI, such as defining the list of common metadata attributes extensions desired for XDS Affinity Domains.
2. The Problem
A lot of XDS Affinity Domains are extending the XDS Registry metadata to include certain radiology specific information: Study Instance UID, Accession Number, etc. Currently this is being done in a purely customized manner so for example, two Registries that have added support for Study Instance UIDs will not have done it in the exact same way. If would be better if there was a standardized way of extending XDS metadata. For example, it could be specified that the DICOM attribute Tag number shall be used in a specific way if a DICOM attribute is to be used in the metadata.
3. Key Use Case
Metadata is typically being extended in order to improve performance. Putting key Study Level attributes in the XDS Registry means that many Study level query use cases can be supported by a Consumer only having to query the Registry rather than also having to query the Repositories to retrieve and parse the XDS-I.b Manifests to obtain Study Level information.
Typically XDS Affinity Domains want to extend their XDS Registry to support the following additional attributes:
- Study Instance UID
- Accession Number
- Study ID
4. Standards and Systems
The Supplement would define a standardized way in which XDS metadata can be extended for radiology related attributes.
5. Technical Approach
This work item would be dependent upon the ITI Technical Committee to define the standardized way in which XDS metadata can be extended. IHE Radiology would then leverage this work to define how XDS metadata can be extended for radiology related attributes.
Metadata extension effects more than just XDS and XDS-I, as there are other Profiles that utilize this metadata (XDR, XDM, etc.). So likely the best mechanism to address this work item would be to add an Annex to the Technical Framework defining how metadata should be extended. Other Profiles could then just be updated to include comments about metadata extension and a reference to this Annex.
6. Support & Resources
A number of groups have expressed interest in this proposal and are able to provide resources. Among these are:
- Canada Infoway SCWG5 DI members
- A number of Canadian XDS Affinity Domains
7. Risks
This work item has a dependency on work being done in the ITI Technical Committee.
8. Open Issues
<Point out any key issues or design problems. This will be helpful for estimating the amount of work and demonstrates thought has already gone into the candidate profile.>
9. Tech Cmte Evaluation
<The technical committee will use this area to record details of the effort estimation, etc.>
Effort Evaluation (as a % of Tech Cmte Bandwidth):
- 20% but needs more details on approach.
Responses to Issues:
- See italics in Risk and Open Issue sections
Candidate Editor:
- TBA