DICOM PS3.2 2019a - Conformance

B.4 Networking

B.4.1 Implementation Model

B.4.1.1 Application Data Flow

Application Data Flow Diagram

Figure B.4.1-1. Application Data Flow Diagram


  • The Storage Application Entity sends images and Presentation States to a remote AE. It is associated with the local real-world activity "Send Images & GSPS". "Send Images & GSPS" is performed upon user request for each study completed or for specific images selected. When activated by user's settings (auto-send), each marked set of images and associated Presentation States can be immediately stored to a preferred destination whenever a Patient/Study is closed by the user. If the remote AE is configured as an archive device the Storage AE will request Storage Commitment and if a commitment is successfully obtained will record this information in the local database.

  • The Workflow Application Entity receives Worklist information from and sends MPPS information to a remote AE. It is associated with the local real-world activities "Update Worklist" and "Acquire Images". When the "Update Worklist" local real-world activity is performed the Workflow Application Entity queries a remote AE for worklist items and provides the set of worklist items matching the query request. "Update Worklist" is performed as a result of an operator request or can be performed automatically at specific time intervals. When the "Acquire Images" local real-world activity is performed the Workflow Application Entity creates and updates Modality Performed Procedure Step instances managed by a remote AE. Acquisition of images will result in automated creation of an MPPS Instance. Completion of the MPPS is performed as the result of an operator action.

  • The Hardcopy Application Entity prints images on a remote AE (Printer). It is associated with the local real-world activity "Film Images". "Film Images" creates a print-job within the print queue containing one or more virtual film sheets composed from images selected by the user.

B.4.1.2 Functional Definition of AEs

B.4.1.2.1 Functional Definition of Storage Application Entity

The existence of a send-job queue entry with associated network destination will activate the Storage AE. An association request is sent to the destination AE and upon successful negotiation of a Presentation Context the image transfer is started. If the association cannot be opened, the related send-job is set to an error state and can be restarted by the user via job control interface. By default, the Storage AE will not try to initiate another association for this send-job automatically. However, an automatic retry (retry-timer, retry­count) can be configured by a CSE.

B.4.1.2.2 Functional Definition of Workflow Application Entity

Worklist Update attempts to download a Worklist from a remote node. If the Workflow AE establishes an Association to a remote AE, it will transfer all worklist items via the open Association. During receiving the worklist response items are counted and the query processing is canceled if the configurable limit of items is reached. The results will be displayed in a separate list, which will be cleared with the next Worklist Update.

The Workflow AE performs the creation of a MPPS Instance automatically whenever images are acquired. Further updates on the MPPS data can be performed interactively from the related MPPS user interface. The MPPS "Complete" or "Discontinued" states can only be set from the user interface.

B.4.1.2.3 Functional Definition of Hardcopy Application Entity

The existence of a print-job in the print queue will activate the Hardcopy AE. An association is established with the printer and the printer's status determined. If the printer is operating normally, the film sheets described within the print-job will be printed. Changes in printer status will be detected (e.g., out of film) and reported to the user. If the printer is not operating normally, the print-job will set to an error state and can be restarted by the user via the job control interface.

B.4.1.3 Sequencing of Real-World Activities

Sequencing Constraints

Figure B.4.1-2. Sequencing Constraints


Under normal scheduled workflow conditions the sequencing constraints illustrated in Figure B.4.1-2 apply:

  1. Query Worklist

  2. Receive Worklist of Modality Scheduled Procedure Steps (MSPS)

  3. Select Workitem (MSPS) from Worklist

  4. Start acquisition and create MPPS

  5. Acquire Images

  6. Complete acquisition and finalize MPPS

  7. Print acquired images (optional step)

  8. Store acquired images and any associated Grayscale Softcopy Presentation State (GSPS) instances.

  9. If the Image Manager is configured as an archive device the Storage AE will request Storage Commitment for the images and associated GSPS instances.

Other workflow situations (e.g., unscheduled procedure steps) will have other sequencing constraints. Printing could equally take place after the acquired images have been stored. Printing could be omitted completely if no printer is connected or hard copies are not required.

DICOM PS3.2 2019a - Conformance