How to build relationship between '$.procedureCode' and '$.reasonCode' on imagingstudy

There are ‘$.procedureCode’ and ‘$.reasonCode’ on resource imagingstudy. If each reasonCode based on one procedureCode, How to build the relationship? Add extension in ‘$.reasonCode’ to set its procedureCode?

Is this a situation where there are 100s of procedure codes and a large number of reason codes, but there’s a relationship where certain procedures must be supported by a particular subset of reasons?

Yes, If each reason based on a certain procedure, How to build the relationship with ‘$.procedureCode’ and ‘$.reasonCode’ on resource imagingstudy?

The relationship on the ImagingStudy is implicit in the fact they’re on the same study. However, if you want to define what combinations are allowed, there isn’t really a clean way to do that right now. You could possibly extend ConceptMap to support the use-case, though that’s not really what it’s for.

The multiple procedure codes in ImagingStudy are to handle the fact that a CT of the head, CT of the neck and CT of the chest might be ordered as three procedures. These would be typically tied to a single reason for performing the exam.

When the patient is on the gantry, the technologist will just run it as one continuous image collection, resulting in one DICOM Study (which shows up in FHIR as one ImagingStudy).

I can’t immediately think of a situation where a single ImagingStudy is the result of multiple unrelated procedures, each with a different motivation.