DICOM tags to use to mark instances for inclusion in a particular project

49 views
Skip to first unread message

Philippe Després

unread,
Mar 28, 2019, 1:03:46 PM3/28/19
to Orthanc Users
Hi, 

I posted this question on the comp.protocol.dicom group (sorry for cross-posting) but this might prompt a response from the Orthanc community:

what would be the DICOM tags to use to mark instances for inclusion in a particular project. Say I want to tag instances with a project code (e.g. "MyProject") to easily retrieve all images/SR belonging to this collection? 

I plan on using the studies/{id}/modify method to tag studies belonging to a particular project.

I search the forum but could not find a satisfying answer. 

Best, 

Philippe 

Luiz Eduardo Guida Valmont

unread,
Mar 28, 2019, 1:23:17 PM3/28/19
to Philippe Després, Orthanc Users
Hi, Philippe!

I understand your tag to be very specific. Because of that, I suggest you work with private tags. I apologise if you're aware of that which I'm about to write, but I struggled a lot with it in the past so I'll try to save you some time.

You'll want to define a custom dictionary in Orthanc configuration. Suppose your company name is ACME. The Dictionary tag in Orthanc.json would read something like this:
{
  ...
  "Dictionary": {
    "2345,FA01": [ "<VR>", "ProjectCode", 1, 1, "ACME" ]
  }
  ...
}
NOTE: VR is the Value Representation, the type of the ProjectCode tag

Then you'll want to place TWO tags in your image:
  • The reservation tag formatted as "2345,00FA": the 2345 is the same as the group number from the tag itself, whereas the 00FA element tells us you're reserving from "2345,FA00" to "2345,FAFF"
  • The tag per se, as presented above
Don't forget to pick an odd group number (odd groups are reserved for private tagging). If you can predict through reasearch/collection which private tags are already used, you might be better off to selecting a group number that won't give you headaches down the road.

Still, if say "5555,AAxx" is already reserved, you can resort to "5555,ABxx" without a problem.

Let me know if you have any further questions.

Best,
--
Luiz Eduardo

Reply all
Reply to author
Forward
0 new messages