This page is part of the MII Implementation Guide Bildgebung (v2027.0.0-ballot.1: Release) based on FHIR (HL7® FHIR® Standard) R4. This is the current published version. For a full list of available versions, see the Directory of published versions

Code Systems

This page describes the terminologies used by the Bildgebung module and the code systems the module defines. The complete, automatically generated list of all code systems can be found in the artifact overview.

DICOM

DICOM is the leading standard protocol for managing and transmitting medical image data. It is used to identify and transfer imaging studies and forms the basis for the data referenced in ImagingStudy profiles.

For the following tags, dedicated code systems were created so that tags with enumerated values can be represented in a queryable way:

(0018,0020) Scanning Sequence -> ImagingStudy extension MR scanningSequence
(0018,0021) Sequence Variant -> ImagingStudy extension MR scanningSequenceVariant
(0008,0008) Image Type -> ImagingStudy extension instance details imageType
(0054,1000) Series Type -> ImagingStudy extension PT seriesType

For the transducer type of the US modality, a dedicated code system was also created to list the codes semantically correctly according to the FHIR standard:

(0018,6031) Transducer Type -> ImagingStudy extension US transducerType

SNOMED CT

SNOMED CT is used to code clinical concepts related to imaging procedures, including the indications for an examination, the type of procedure performed and the findings observed. For mapping the body region represented in DICOM to the SNOMED standard, a table exists: https://dicom.nema.org/medical/dicom/current/output/chtml/part16/chapter_L.html

LOINC & RadLex

LOINC is used to code observations and results of imaging procedures, particularly in connection with the DiagnosticReport profile. RadLex is a comprehensive lexicon specific to radiology containing terms for imaging procedures, anatomical structures, findings and imaging techniques. An existing mapping of RadLex codes to the more widely used LOINC standard is available at: https://playbook.radlex.org/playbook/SearchRadlexAction

Further code systems used

• identifierType: https://terminology.hl7.org/6.0.2/CodeSystem-v2-0203.html
• diagnosticServiceSectionId: https://terminology.hl7.org/6.0.2/CodeSystem-v2-0074.html
• observationType: https://terminology.hl7.org/6.0.2/CodeSystem-v2-0936.html
• Observation Category Codes: https://terminology.hl7.org/6.0.2/CodeSystem-observation-category.html

Units of measurement for measured values MUST be given in UCUM units so that results can be converted into one another. Validators can be used to ensure that the units used are valid.