Материал: part02

Page 86​ DICOM PS3.2 2020a - Conformance​

Table B.1-2 provides an overview of the Media Storage Application Profiles supported by Example-Integrated-Modality.​

Table B.1-2. Media Services​

B.2 Table of Contents​

A table of contents shall be provided to assist readers in easily finding the needed information.​

B.3 Introduction​

B.3.1 Revision History​

Table B.3.1. Revision History​

B.3.2 Audience, Remarks, Terms and Definitions, Basics of DICOM Communication, Abbrevi-​ ations, References​

See example text in Section A.3.​

B.3.3 Additional Remarks for This Example​

ThisdocumentisasampleDICOMConformanceStatementcreatedforDICOMPS3.2.Itistobeusedsolelyasanexampletoillustrate​ howtocreateaDICOMConformanceStatementforanacquisitionmodality.Thesubjectofthedocument,EXAMPLE-INTEGRATED-​ MODALITY, is a fictional product.​

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B.4 Networking​

B.4.1 Implementation Model​

B.4.1.1 Application Data Flow​

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​ timeintervals.Whenthe"AcquireImages"localreal-worldactivityisperformedtheWorkflowApplicationEntitycreatesandupdates​ 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.​

•​TheHardcopyApplicationEntityprintsimagesonaremoteAE(Printer).Itisassociatedwiththelocalreal-worldactivity"FilmImages".​ "Film Images" creates a print-job within the print queue containing one or more virtual film sheets composed from images selected​ by the user.​

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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​ processingiscancelediftheconfigurablelimitofitemsisreached.Theresultswillbedisplayedinaseparatelist,whichwillbecleared​ 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​

1. Query Worklist

2.Receive Worklist

3.Select Work item (MSPS)

4.Start Acquisition (Create MPPS)

5.Acquire Images

6.Complete Acquisition (Finalize MPPS)

7.Print Acquired Images (optional)

8.Store Acquired Images &GSPS

9.Commit Acquired Images & GSPS

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​

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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.​

B.4.2 AE Specifications​

B.4.2.1 Storage Application Entity Specification​

B.4.2.1.1 SOP Classes​

EXAMPLE-INTEGRATED-MODALITY provides Standard Conformance to the following SOP Classes:​

Table B.4.2-1. SOP Classes for AE Storage​

B.4.2.1.2 Association Policies​

B.4.2.1.2.1 General​

The DICOM standard application context name for DICOM is always proposed:​

Table B.4.2-2. DICOM Application Context for AE Storage​

EXAMPLE-INTEGRATED-MODALITY initiates one Association at a time for each destination to which a transfer request is being​ processed in the active job queue list. Only one job will be active at a time, the other remains pending until the active job is completed​ or failed.​

Table B.4.2-3. Number of Associations Initiated for AE Storage​

Maximum number of simultaneous Associations​ 1 (configurable)​

EXAMPLE-INTEGRATED-MODALITYacceptsAssociationstoreceiveN-EVENT-REPORTnotificationsfortheStorageCommitment​

Push Model SOP Class.​

Table B.4.2-4. Number of Associations Accepted for AE Storage​

Maximum number of simultaneous Associations​ 5 (configurable)​

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B.4.2.1.2.3 Asynchronous Nature​

EXAMPLE-INTEGRATED-MODALITYdoesnotsupportasynchronouscommunication(multipleoutstandingtransactionsoverasingle​

Association).​

Table B.4.2-5. Asynchronous Nature as a SCU for AE Storage​

B.4.2.1.3 Association Initiation Policy​

B.4.2.1.3.1 Activity - Send Images​

B.4.2.1.3.1.1 Description and Sequencing of Activities​

A user can select images and presentation states and request them to be sent to multiple destinations (up to 3). Each request is for-​ warded to the job queue and processed individually. When the "Auto-send" option is active, each marked instance or marked set of​ instances stored in database will be forwarded to the network job queue for a pre-configured auto-send target destination. Which in-​ stances will be automatically marked and the destination where the instances are automatically sent to can be configured. The "Auto-​ send" is triggered by the Close Patient user application.​

The Storage AE is invoked by the job control interface that is responsible for processing network archival tasks. The job consists of​ data describing the instances marked for storage and the destination. An internal daemon process triggered by a job for a specific​ network destination initiates a C-STORE request to store images. If the process successfully establishes an Association to a remote​ Application Entity, it will transfer each marked instance one after another via the open Association. Status of the transfer is reported​ through the job control interface. Only one job will be active at a time. If the C-STORE Response from the remote Application contains​ a status other than Success or Warning, the Association is aborted and the related Job is switched to a failed state. It can be restarted​ any time by user interaction or, if configured, by automated retry.​

The Storage AE attempts to initiate a new Association in order to issue a C-STORE request. If the job contains multiple images then​ multiple C-STORE requests will be issued over the same Association.​

If the Remote AE is configured as an archive device the Storage AE will, after all images and presentation states have been sent,​ transmit a single Storage Commitment request (N-ACTION) over the same Association. Upon receiving the N-ACTION response the​ Storage AE will delay releasing the Association for a configurable amount of time. If no N-EVENT-REPORT is received within this​ time period the Association will be immediately released (i.e., notification of Storage Commitment success or failure will be received​ over a separate association). However, the Storage AE is capable of receiving an N-EVENT-REPORT request at any time during an​ association provided a Presentation Context for the Storage Commitment Push Model has been successfully negotiated (i.e., the N-​ ACTION is sent at the end of one association and the N-EVENT-REPORT is received during an association initiated for a subsequent​ send job or during an association initiated by the Remote AE for the specific purpose of sending the N-EVENT-REPORT).​

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