ImagingStudy — detail: DICOM linkage

Bridge between the DICOM PACS (Picture Archiving and Communication System) and FHIR REST. ImagingStudy exposes a DICOM Study via the FHIR API without duplicating pixels.

DICOM <-> FHIR pivot

ImagingStudy does not transport pixels. It carries only the descriptive structure of a DICOM Study: Study Instance UID, Series, Instance UID. The pixels themselves stay in the PACS and are retrieved via WADO-RS (DICOMweb), QIDO-RS for search, STOW-RS for storage.

series/instance structure

• ImagingStudy = DICOM Study level. An urn:oid:UID identifier.
• series[] = DICOM Series level. A modality (MR, CT, US, XA, ...), a bodySite, a description.
• series.instance[] = DICOM SOP Instance level. A SOP Class UID + SOP Instance UID.

WADO-RS access

To retrieve pixels:

• GET {endpoint.address}/studies/{studyUID} — full DICOM Study as multipart/related (DICOM MIME).
• GET {endpoint.address}/studies/{studyUID}/series/{seriesUID}/instances/{instanceUID}/frames/1 — frame as JPEG/PNG/multipart.
• GET {endpoint.address}/studies/{studyUID}/metadata — DICOM metadata as JSON.

Example: brain MRI

{
  "resourceType": "ImagingStudy",
  "id": "study-mri-brain-001",
  "identifier": [{
    "system": "urn:dicom:uid",
    "value": "urn:oid:1.2.826.0.1.3680043.8.498.123456789"
  }],
  "status": "available",
  "modality": [{
    "system": "http://dicom.nema.org/resources/ontology/DCM",
    "code": "MR",
    "display": "Magnetic Resonance"
  }],
  "subject": { "reference": "Patient/marie-dupont" },
  "encounter": { "reference": "Encounter/enc-2026-05-18" },
  "started": "2026-05-18T10:30:00+02:00",
  "basedOn": [{ "reference": "ServiceRequest/sr-brain-mri-001" }],
  "referrer": { "reference": "Practitioner/dr-neurologue" },
  "interpreter": [{ "reference": "Practitioner/dr-radiologue" }],
  "endpoint": [{ "reference": "Endpoint/pacs-wadors-acme" }],
  "numberOfSeries": 4,
  "numberOfInstances": 752,
  "description": "Brain MRI 3T with contrast",
  "series": [{
    "uid": "1.2.826.0.1.3680043.8.498.123456789.1",
    "number": 1,
    "modality": {
      "system": "http://dicom.nema.org/resources/ontology/DCM",
      "code": "MR"
    },
    "description": "T1 axial",
    "numberOfInstances": 180,
    "bodySite": {
      "concept": { "coding": [{
        "system": "http://snomed.info/sct",
        "code": "12738006",
        "display": "Brain"
      }] }
    }
  }]
}

Common pitfalls

• Non-OID UID — DICOM mandates OID UIDs. Always use urn:dicom:uid + urn:oid: in value.
• No endpoint — without an Endpoint pointing to the PACS WADO-RS, the client has no way to access pixels.
• Missing series-level modality — each series must carry a modality, or viewers cannot decode it.
• Inconsistent numberOfInstances — verify the sum of series.instance against the declared total.

Related resources

• ImagingStudy — overview
• ImagingSelection
• ServiceRequest
• DiagnosticReport