Modality Worklist
A Modality Worklist is the DICOM service that lets an imaging device query a scheduled list of patients and procedures from a worklist provider, so demographics do not have to be typed in again at the scanner.
What Modality Worklist means in practice
The modality asks for the day's scheduled procedures and receives the patient identifiers, accession number and procedure details already recorded upstream. Beyond saving time, this is the mechanism that keeps identifiers consistent: a study acquired from a worklist entry carries the same patient ID and accession number as the order it came from, so it files correctly without manual reconciliation.
Source
This definition follows NEMA PS3.4 Annex K — Basic Worklist Management Service, published by NEMA as part of the DICOM standard.
Related terms
C-STORE
C-STORE is the DICOM network service used to transfer a composite object — an image or similar instance — from one device to another, and it is the operation behind "sending a study" to a PACS.
PACS
A PACS is a system that stores, retrieves, distributes and displays medical images, connected to imaging modalities and viewing workstations over a DICOM network.
Patient, Study, Series and Instance
DICOM organises imaging data in a four-level hierarchy: a Patient has Studies (one imaging visit each), a Study has Series (one acquisition run each), and a Series has Instances (the individual images or objects).
Related on this site: Worklist and console integration.