This is the CodeSystem that contains all the codes in RadLex radiology lexicon (http://radlex.org) and RadLex radiology lexicon (http://radlex.org). E.g. what you have to deal with if you get resources containing codes in either of them
Generated Narrative: CodeSystem d90c6776-070a-4707-b535-0a35f2e2298a-464
This code system http://hl7.org/fhir/comparison/CodeSystem/d90c6776-070a-4707-b535-0a35f2e2298a-464 defines codes, but no codes are represented here
http://hl7.org/fhir/comparison/CodeSystem/d90c6776-070a-4707-b535-0a35f2e2298a-464