Finding/diagnosis definitions
A finding/diagnosis definition is the shared anchor for one concept, such as pulmonary nodule or acute pyelonephritis. When a radiologist, a technologist, or an AI describes a pulmonary nodule seen on a patient’s exam, that description can refer to the definition, tying this specific pulmonary nodule to all the relevant context about pulmonary nodules.
What a definition carries
- Identity. A name, synonyms, and a written definition.
- Attributes. The things that characterize an instance, each with its allowed values or units: whether it is present; categorical descriptors such as composition; measurements such as mean diameter.
- Where it occurs. Its anatomic scope: lung for a pulmonary nodule.
- How it is seen. The modalities that show it: CT for a pulmonary nodule.
- Codes. Its identities in outside terminologies, such as RadLex and SNOMED CT.
- Relationships. How it relates to other definitions: a part-solid pulmonary nodule is a subtype of pulmonary nodule; a pulmonary nodule is assessed by Lung-RADS; a diagnosis may manifest as it.
Two collections, one kind of content
Open Imaging Finding Models are an inclusive collection maintained by the OIDM project. They are meant for rapid, community-based prototyping, and anyone can propose changes. A definition can start as little more than a name and a description and improve over time.
ACR/RSNA Common Data Elements are the well-reviewed collection, maintained by the American College of Radiology and the Radiological Society of North America and published through radelement.org.
The two describe the same ideas and will share the same schema. Finding models are the beta channel, with rapid additions and updates; Common Data Elements are the release channel, reviewed and stable. They stay cross-linked: when a definition migrates into the CDEs, it is still maintained as a finding model and carries a reference to its CDE identity.
Where both are going
Both collections are document-oriented today. Both are moving onto the next-generation schema, a graph of interconnected concepts being developed in the ACR/RSNA CDE project, so that applications can use them together. That move is an immediate priority.