DD.3.2.2 N-GET

The N-GET is used to get the verification status and results of the applicable Machine Verification SOP Class.

DD.3.2.2.1 Verification Parameters Selector Attribute Macro

Table DD.3.3.2.2.1-1 describes N-GET support requirements for the Selector Attribute Macro. See Section 5.4 for requirements type code meaning.

Table DD.3.2.2.1-1 VERIFICATION PARAMETERS SELECTOR ATTRIBUTE MACRO

Attribute Name Tag Req. Type N-GET (SCU/SCP)
Selector Attribute (0072,0026) -/1
Selector Value Number (0072,0028) -/1
Selector Sequence Pointer (0072,0052) -/1
Selector Sequence Pointer Private Creator (0072,0054) -/1
Selector Sequence Pointer Items (0074,1057) -/1
Selector Attribute Private Creator (0072,0056) -/1

DD.3.2.2.2 Attributes

The attribute list of the N-GET for the RT Conventional Machine Verification SOP Class and RT Ion Machine Verification SOP Class is shown in Table DD.3.2.2.2-1. See Section 5.4 for usage notation.

Table DD.3.2.2.2-1

N-GET ATTRIBUTE LIST– RT CONVENTIONAL MACHINE VERIFICATION SOP CLASS AND RT ION MACHINE VERIFICATION SOP CLASS

Attribute Name Tag Usage SCU/SCP
Referenced RT Plan Sequence (300C,0002) -/1
>Referenced SOP Class UID (0008,1150) -/1
>Referenced SOP Instance UID (0008,1155) -/1
Referenced Fraction Group Number (300C,0022) -/1
Patient ID (0010,0020) -/1
Include ‘Issuer of Patient ID Macro’ DICOM Supplement 96 Table UUU.2.5-2e
Treatment Verification Status (3008,002C) -/1
Failed Parameters Sequence (0074,1048) -/2 (zero or more items shall be included in this Sequence)
>Include ‘Verification Parameters Selector Attribute Macro’ Table DD.3.2.2.1-1
Overridden Parameters Sequence (0074,104A) -/2 (zero or more items shall be included in this Sequence)
>Include ‘Verification Parameters Selector Attribute Macro’ Table DD.3.2.2.1-1
>Operators’ Name (0008,1070) -/2
>Override Reason (3008,0066) -/2
All other attributes - 3/2

DD.3.2.2.3 Status

The status values which are specific for these SOP Classes are defined as follows:

Table DD.3.2.2.3-1

RT CONVENTIONAL MACHINE AND RT ION MACHINE VERIFICATION SOP CLASS N-GET STATUS VALUES

Status Meaning Code
Success Treatment Verification Status of the applicable Machine Verification instance successfully returned. 0000
Failure No such object instance – applicable Machine Verification instance not found C112

DD.3.2.2.4 Behavior

The SCU uses N-GET to retrieve from the SCP the verification status and results of the applicable Machine Verification SOP Instance.

The SCP shall return the Treatment Verification Status (3008,002C) attribute as well as the status code of the requested SOP Instance update. Treatment Verification Status shall have one of the following values:

VERIFIED = treatment verified

VERIFIED_OVR = treatment verified with at least one out-of-range value overridden

NOT_VERIFIED = verification of treatment was not successful

The VERIFIED state indicates that all required parameters have been checked and no out-of-range values have been detected. The VERIFIED_OVR state indicates that the treatment failed to verify due to one or more out-of-range values which were then overridden. NOT_VERIFIED indicates that one of more of the out-of-range values has not yet been overridden and the treatment cannot go ahead. This could be because at least one out-of-range value was detected, or one or more values required for verification were not supplied. The site- and vendor-specific configuration of the MPV determines the attributes and ranges required for successful verification.

If the Treatment Verification Status is VERIFIED_OVR, one or more parameter occurrences shall be returned in Overridden Parameters Sequence (0074,104A), otherwise the sequence shall be empty.

If the Treatment Verification Status is NOT_VERIFIED, one or more parameter occurrences shall be returned in Failed Parameters Sequence (0074,1048), otherwise the sequence shall be empty.

See PS 3.3 Section C.31.1.1 for specification of how the attribute tags and position within a sequence are encoded.

The SCP shall return the status code of the requested action. The meanings of success, warning and failure status codes are defined in Section DD.3.2.2.3.