Thanks Nick The question here really isn't about the semantics of the DICOM identifiers, though I thank you for reviewing those. The question is about how these interact with an openEHR system and with other users of the archetype
One interesting aspect concerning the OIDs is that though they are supposed to be globally unique, unless you have a oid root <--> issuing system registry, you still need to track the issuing system (and I've never heard of such a registry in practice) Grahame On Tue, Jan 18, 2011 at 8:24 PM, Nick Brown <nbrown.mimic at btinternet.com>wrote: > Hi Grahame > > DICOM UIDs are globally unique ISO OIDS expressed in a specified text > format. Also specified in an ISO standard called GUSI (Globally Unique > String Identifiers). So storing them as ASCII text strings of max length 64 > bytes is actually how DICOM uses them. > > Within a department each four digit identifiers called Accession numbers > are used as identifiers usually to identify a folder that holds the results > arising from a specific request for an imaging procedure to be performed. > When they get to 9999 they start again at 0001. > > The IHE SWF Profile specifies a way to use DICOM and HL7 date elements to > manage the process of creating results as a result of a request. It used > DICOM UIDs to identify various data objects including any image data objects > that are produced. DICOM has its own way of searching for images which > requires a set of UIDs to identify the image and where it can be found. > These were originally designed for use within a department but are now being > used for communication between departments. > > All data DICOM data object have to use the image data object structure even > reports or notes. > > Hope this helps > > I am copying the supplier co-chair of the British Institute of Radiology > (BIR) Medical Imaging and Radiation oncology committee who is a past > director of an organsiation called PACSnet and is a key expert on these > matters. > > BTW so far as I know DICOM does not support the concept of different > revisions of the same data object. (Called a SOP instance in DICOM speak.) > > > Best wishes > Nick > > --- On *Tue, 18/1/11, Grahame Grieve <grahame at kestral.com.au>* wrote: > > > From: Grahame Grieve <grahame at kestral.com.au> > Subject: Use of Identifiers in archetypes > To: "For openEHR technical discussions" <openehr-technical at openehr.org> > Date: Tuesday, 18 January, 2011, 4:31 > > hi Tom > > I was working with Heather today on the imaging exam archetype. Two > different considerations associated with identifiers came up during our > work. > > The first is that in the archetype design we came up with (still be posed > on CKM yet), there's a lot of identifiers present. These identifiers are > required to deal with the interoperability aspects of the imaging exam > report (i.e. PACS reigsters images with RIS, RIS provides report to > EHR, EHR tracks identifiers so it can provide links to RIS/PACS > resources as required). In particular, in several places there's slots > for various DICOM UIDs. To me, these are IT issues, not clinical > issues, so they shouldn't be part of the archetype design (on the basis > that archetypes are *clinica* knowledge)- but I do know that we > absolutely need these identifiers. Is there a policy about this? > Note that I ask this question with wider issues about whether IT and > interoperability concerns should be explicitly represented in archetypes. > > The second question is that there seemed to be some operating > guidance to archetype designers to use the Text data type rather than > the Identifier type for these fields talked about above on the basis that > they are "foreign" identifiers. There didn't seem to be particular > consensus on where this policy came from (and I don't want to point > fingers...) but it seems pretty nuts to me. These things should be > identifiers, and we should insist on tracking the issuer of them (though > I couldn't care less about the type, and indeed, the presence of type > on DV_Identifier represents confused modeling). In our archetype, we > changed all the identifiers from Text to Identifier. Is there any rules > about this? > > Grahame > _______________________________________________ > openEHR-technical mailing list > openEHR-technical at openehr.org<http://mc/compose?to=openEHR-technical at > openehr.org> > http://lists.chime.ucl.ac.uk/mailman/listinfo/openehr-technical > > > _______________________________________________ > openEHR-technical mailing list > openEHR-technical at openehr.org > http://lists.chime.ucl.ac.uk/mailman/listinfo/openehr-technical > > -- ------------- Grahame Grieve, Health Intersections Pty Ltd. grahame at healthintersections.com.au | http://www.healthintersections.com.au -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.openehr.org/mailman/private/openehr-technical_lists.openehr.org/attachments/20110118/19af72ab/attachment.html>
