HL7

Health Level Seven — the messaging standard hospitals use for orders and patient data alongside DICOM.

HL7 is the messaging standard that carries non-image data around a hospital — patient demographics, orders, and reports — while DICOM carries the images. The two must agree: when an HL7 order and the DICOM header disagree on, say, patient name or accession number, reconciliation fixes the DICOM tags to match the authoritative RIS record.