This is the ValueSet that contains all the codes in Anatomical Region (http://hl7.eu/fhir/imaging-manifest-r5/ValueSet/im-anatomical-region-valueset) and Anatomical Region (http://hl7.eu/fhir/imaging-manifest-r5/ValueSet/im-anatomical-region-valueset). E.g. what you have to deal with if you get resources containing codes in either of them