Body region
A coarse anatomic grouping, one level above an organ and well above a named structure. Regions do three jobs in OIDM: they classify an anatomic location, they carry broad anatomy on a finding model where precise anatomy belongs in anatomic_locations, and they provide the fallback when a finding names no anatomic structure at all.
The fallback rule is explicit. Only findings with no anatomic noun, such as “soft tissue mass” or “generalized osteoporosis,” fall back to the exam-scoped coarse region, and the grain is “the coarse region, not a soft-tissue substructure.” The rule also states that “organ always wins over exam-region” whenever the finding has a real target organ, including edge-of-exam cases: “no consolidation” on an abdominal CT codes to lung, never to abdomen.1
Synonyms and near-synonyms
- Region and anatomic region are the same thing;
regionis the field name on a location. - Body system is orthogonal. Cardiovascular is a system, thorax is a region.
- Category in a finding taxonomy row is described as “an independent anatomic grouping” and behaves like a region but is not the same list.
- Exam-scoped region means a region chosen from the exam type rather than from the report text.
Identifier form
No identifier. Regions are enumerated strings, and the fallback rule maps each one to a RadLex RID, for example abdomen to RID56, thorax to RID1243, head to RID9080.1
Where it is used
Data model, Finding model format, and Imaging Problem List viewer.
Conflicts
Four different region lists are in use and none is a superset of the others. The anatomic-locations package enumerates Head, Neck, Thorax, Abdomen, Pelvis, Upper Extremity, Lower Extremity, Breast, and Body.2 The documented finding-model metadata field uses head, neck, chest, breast, abdomen, pelvis, spine, upper_extremity, lower_extremity, and whole_body, with legacy title-cased values normalizing and the legacy alias ALL mapping to whole_body.3 The extraction schema uses chest, abdomen, pelvis, head, neck, spine, upper extremity, lower extremity, and breast.4 The viewer filters on Chest, Abdomen, Pelvis/GU, Musculoskeletal, and Head/Neck. Thorax and chest, and the presence or absence of spine, are the recurring mismatches.