Q.4.2 Service Definition

Two peer DICOM AEs implement this Relevant Patient Information Query Service Class with one serving in the SCU role and one serving in the SCP role. The SOP Class is implemented using the DIMSE-C C-FIND service as defined in PS 3.7.

Only a baseline behavior of the DIMSE-C C-FIND is used in this Service Class.

A C-FIND service conveys the following semantics:

— The SCU requests that the SCP perform a match for the Matching Keys and return values for the Return Keys that have been specified in the Identifier of the request, against the Relevant Patient Information that the SCP possesses.

Note: In this Annex, the term "Identifier" refers to the Identifier service parameter of the C-FIND service as defined in PS 3.7.

— The SCP generates a C-FIND response for at most one match with an Identifier containing the values of all Matching Key Attributes and all known Return Key Attributes requested. The response contains one relevant patient information instance in the form that matches the Template that was requested. This response shall contain a status of Pending.

— When the process of matching is complete, with zero or one match, a C-FIND response is sent with a status of Success and no Identifier.

— A Failed response to a C-FIND request indicates that the SCP is unable to process the request. This shall be used to indicate that the requested template is not supported by the SCP, or that more than one match was found by the SCP.

— The SCU may cancel the C-FIND service by issuing a C-FIND-CANCEL request at any time during the processing of the C-FIND service. The SCP will interrupt all matching and return a status of Canceled.

Note: The SCU needs to be prepared to receive C-FIND responses sent by the SCP until the SCP finally processes the C-FIND-CANCEL request.