Imaging Object Change Management - Detailed Proposal
1. Proposed Workitem:
- Proposal Editor: Kevin O'Donnell
- Whitepaper Editor: Kinson Ho (Agfa)
- David Heaney? (McKesson)
- Domain: Radiology, Cardiology
Summary
<Summarize in a few lines the existing problem . E.g. "It is difficult to monitor radiation dose for individual patients and almost impossible to assemble and compare such statistics for a site or a population.">
<Demonstrate in a line or two that the key integration features are available in existing standards. E.g. "DICOM has an SR format for radiation dose events and a protocol for exchanging them.">
<Summarize in a few lines how the problem could be solved. E.g. "A Radiation Dose profile could require compliant radiating devices to produce such reports and could define transactions to actors that collect, analyze and present such information.">
<Summarize in a line or two market interest & available resources. E.g. "Euratom and ACR have published guidelines requiring/encouraging dose tracking. Individuals from SFR are willing to participate in Profile development.">
<Summarize in a line or two why IHE would be a good venue to solve the problem. E.g. "The main challenges are dealing with the chicken-and-egg problem and avoiding inconsistent implementations.">
- A whitepaper from IHE to document the detailed use cases could be an excellent companion piece of work to the DICOM work item
- Doing the whitepaper now would help inform/direct the DICOM work
- If both are successful, a profile could be built from the completed use cases and mechanisms.
2. The Problem
As the preferred protocol for distributing and storing medical imaging, vast numbers of DICOM objects are created and distributed every day.
For various reasons, it is common to create and distribute multiple copies of instances:
- Providing copies to other sites (or departments) caring for the same patient
- Sending copies for processing (3D, CAD, Clinical Analysis)
- Local caching of instances to compensate for network performance
- Mirroring instances on a Fail-over/Backup server
- Use of multiple "peer" archives
- Migrating to a new PACS system
For various reasons, it is also common to modify instances:
- Correction/update of demographics
- Splitting/combining studies
- Updating references to other related instances
- Taking “bad” images out of circulation
- Coercing instances to fit into local data models/workflow
- Permanently delete old images as may be required by institutional record retention policies
The combination of needing to distribute copies of instances and needing to modify instances leads to copies which are inconsistent which in turn creates the potential for confusion, error or loss of data.
It would be useful to have reliable, efficient mechanisms to know whether two copies of an instance have diverged, what has changed and if and how to synch them.
3. Key Use Case
Central Archive, Local PACS
- i.e. Infoway model
Local Cache
- A group of three hospitals each have local PACS.
- When a patient is transfered to another hospital (e.g. for specialist care), a copy of recent images are transfered to the second hospital.
- The first hospital identifies a demographic change and updates their Master Copy of the images.
- ?? What happens at the second hospital, how??
Features
- delete,
- Undelete,
- superseed/replace,
- Update Patient Demographics,
- Update Procedure Information,
- Merge Patient Records,
- Link/unlink Patient Records,
- Update Study Level Attribute,
- Update Series Level Attributes, and
- Update Image Level Attributes;
- Subscribe/unsubscribe to change notification
- Revision Log
4. Standards & Systems
- DICOM is considering a work item for Data Consistency that could provide mechanisms.
5. Technical Approach
<This section can be very short but include as much detail as you like. The Technical Committee will flesh it out when doing the effort estimation.>
<Outline how the standards could be used/refined to solve the problems in the Use Cases. The Technical Committee will be responsible for the full design and may choose to take a different approach, but a sample design is a good indication of feasibility.>
<If a phased approach would make sense indicate some logical phases. This may be because standards are evolving, because the problem is too big to solve at once, or because there are unknowns that won’t be resolved soon.>
Existing actors
<Indicate what existing actors could be used or might be affected by the profile.>
New actors
<List possible new actors>
Existing transactions
<Indicate how existing transactions might be used or might need to be extended.>
New transactions (standards used)
<Describe possible new transactions (indicating what standards would likely be used for each. Transaction diagrams are very helpful here. Feel free to go into as much detail as seems useful.>
Impact on existing integration profiles
<Indicate how existing profiles might need to be modified.>
New integration profiles needed
<Indicate what new profile(s) might need to be created.>
Breakdown of tasks that need to be accomplished
<A list of tasks would be helpful for the technical committee who will have to estimate the effort required to design, review and implement the profile.>
6. Support & Resources
<List groups that have expressed support for the proposal and resources that would be available to accomplish the tasks listed above.>
7. Risks
<List technical or political risks that will need to be considered to successfully field the profile.>
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):
- 35% for ...
Responses to Issues:
- See italics in Risk and Open Issue sections
Candidate Editor:
- TBA