K.4.1.1 C-FIND Service Parameters

K.4.1.1.1 SOP Class UID

The SOP Class UID identifies the Worklist Information Model against which the C-FIND is to be performed. Support for the SOP Class UID is implied by the Abstract Syntax UID of the Presentation Context used by this C-FIND operation.

K.4.1.1.2 Priority

The Priority Attribute defines the requested priority of the C-FIND operation with respect to other DIMSE operations being performed by the same SCP.

Processing of priority requests is not required of SCPs. Whether or not an SCP supports priority processing and the meaning of the different priority levels shall be stated in the Conformance Statement of the SCP.

K.4.1.1.3 Identifier

Both the C-FIND request and response contain an Identifier encoded as a Data Set (see PS 3.5).

K.4.1.1.3.1 Request Identifier Structure

An Identifier in a C-FIND request shall contain

— Key Attributes values to be matched against the values of Attributes specified in that SOP Class.

— Conditionally, the Attribute Specific Character Set (0008,0005). This Attribute shall be included if expanded or replacement character sets may be used in any of the Attributes in the Request Identifier. It shall not be included otherwise.

Note: This means that Specific Character Set (0008,0005) is included if the SCU supports expanded or replacement character sets in the context of this service. It will not be included if expanded or replacement character sets are not supported by the SCU.

— Conditionally, the Attribute Timezone Offset From UTC (0008,0201). This Attribute shall be included if Key Attributes of time are to be interpreted explicitly in the designated local time zone. It shall not be present otherwise, i.e., it shall not be sent with a zero-length value.

The Key Attributes and values allowable for the query shall be defined in the SOP Class definition for the corresponding Worklist Information Model.

K.4.1.1.3.2 Response Identifier Structure

The C-FIND response shall not contain Attributes that were not in the request or specified in this section.

An Identifier in a C-FIND response shall contain:

— Key Attributes with values corresponding to Key Attributes contained in the Identifier of the request (Key Attributes as defined in K.2.2.1.)

— Conditionally, the Attribute Specific Character Set (0008,0005). This Attribute shall be included if expanded or replacement character sets may be used in any of the Attributes in the Response Identifier. It shall not be included otherwise. The C-FIND SCP is not required to return responses in the Specific Character Set requested by the SCU if that character set is not supported by the SCP. The SCP may return responses with a different Specific Character Set.

Note: This means that Specific Character Set (0008,0005) is included if the SCP supports expanded or replacement character sets in the context of this service. It will not be included if expanded or replacement character sets are not supported by the SCP.

— Conditionally, the Attribute Timezone Offset From UTC (0008,0201). This Attribute shall be included if any Attributes of time in the Response Identifier are to be interpreted explicitly in the designated local time zone. It shall not be present otherwise, i.e., it shall not be sent with a zero-length value.

— Conditionally, the Attribute HL7 Structured Document Reference Sequence (0040,A390) and its subsidiary Sequence Items. This Attribute shall be included if HL7 Structured Documents are referenced within the Identifier, e.g., in the Pertinent Documents Sequence (0038,0100).

K.4.1.1.4 Status

Table K.4.-1 defines the status code values which might be returned in a C-FIND response. Fields related to status code values are defined in PS 3.7.

Table K.4-1C-FIND RESPONSE STATUS VALUES

Service Status Further Meaning Status Codes Related Fields
Failure Refused: Out of Resources A700 (0000,0902)
Identifier Does Not Match SOP Class A900 (0000,0901) (0000,0902)
Unable to process Cxxx (0000,0901) (0000,0902)
Cancel Matching terminated due to Cancel request FE00 None
Success Matching is complete - No final Identifier is supplied. 0000 None
Pending Matches are continuing - Current Match is supplied and any Optional Keys were supported in the same manner as Required Keys. FF00 Identifier
Matches are continuing - Warning that one or more Optional Keys were not supported for existence for this Identifier. FF01 Identifier

Note: Status Codes are returned in DIMSE response messages (See PS 3.7). The code values stated in column "Status Codes" are returned in Status Command Element (0000,0900).