DICOM PS3.17 2019a - Explanatory Information

ZZZ Content Assessment (Informative)

The following use cases exemplify the use of Content Assessment Results IOD.

ZZZ.1 RT Plan Treatment Assessment Use Case

A RT Plan SOP Instance is sent from a Treatment Planning System (TPS) to a Quality Assurance (QA) Application and to the Treatment Management System (TMS). The TMS de-composes the content for internal storage. At the time of treatment the TMS re-composes the Instance and sends it to the operator console of the linear accelerator. However, during re-composition an error occurs and one jaw specification is omitted from the recomposed Instance and the Beam Dose in the Fraction Scheme Module is set to 0.0.

The operator console requests the QA Application to perform an assessment to compare the copy of the Instance received from the operator console with the copy of the Instance received earlier from the TPS. The QA Application retrieves the Instance from the operator console. The QA Application also performs an assessment by re-calculation of the dosimetric parameters in the assessed plan. Although the Beam Meterset in the assessed plan (from the operator console) is the same as the Beam Meterset in the comparison plan (from the TPS) , the Beam Meterset re-calculated by the QA Application is different due to the missing jaw. Further on it is detected, that all Beam Dose values have the value 0.0.

Beam Meterset for the current treatment device in this example is expressed in Monitor Units.

Table ZZZ.1-1. Content Assessment Results Module Example of a RT Plan Treatment Assessment

Nesting

Attribute Name

Tag

VR

Value

Assessment Label

(0082,0023)

LO

Pre-Treatment Assessment of Fraction 7

Assessment Type Code Sequence

(0082,0021)

SQ

%item

>Code Value

(0008,0100)

SH

121373

>Coding Scheme Designator

(0008,0102)

SH

DCM

>Code Meaning

(0008,0104)

LO

RT Pre-Treatment Consistency Check

%enditem

%endsq

(Assessment Type Code Sequence)

Assessment Set ID

(0082,0016)

LO

ID12345

Assessment Requester Sequence

(0082,0017)

SQ

%item

>Observer Type

(0040,A084)

CS

DEV

>Station Name

(0008,1010)

SH

CONSOLE 1

>Device UID

(0018,1002)

UI

1.2.3.4.5.6.7.8.9.10

>Manufacturer

(0008,0070)

LO

Fancy Linac Inc.

>Manufacturer's Model Name

(0008,1090)

LO

Linear Accelerator Console

>Institution Name

(0008,0080)

LO

RT Clinic 1

>Institution Code Sequence

(0008,0082)

SQ

%item

>>Code Value

(0080,0100)

SH

Clinic1

>>Coding Scheme Designator

(0008,0102)

SH

99MyCounty

>>Code Meaning

(0008,0104)

LO

RT Clinic 1

%enditem

%endsq

(>Institution Code Sequence)

%enditem

%endsq

(Assessment Requester Sequence)

Assessed SOP Instance Sequence

(0082,0004)

SQ

%item

>Referenced SOP Class UID

(0008,1150)

UI

1.2.840.10008.5.1.4.1.1.481.5 (RT Plan Storage)

>Referenced SOP Instance UID

(0008,1155)

UI

1.2.3.4.5.300

%enditem

>Referenced Comparison SOP Instance Sequence

(0082,0005)

SQ

%item

>>Referenced SOP Class UID

(0008,1150)

UI

1.2.840.10008.5.1.4.1.1.481.5 (RT Plan Storage)

>>Referenced SOP Instance UID

(0008,1155)

UI

1.2.3.4.5.300

%enditem

%endsq

(>Referenced Comparison SOP Instance Sequence)

%enditem

%endsq

(Assessed SOP Instance Sequence)

Assessment Summary

(0082,0001)

CS

FAILED

Assessment Summary Description

(0082,0003)

UT

Plan Checker result: Failed!

The assessed RT Plan does not match the reference RT Plan it is compared to. One or more relevant Attributes are not equal. Monitor Unit values and Beam Doses have unreasonable values.

Number of Assessment Observations

(0082,0006)

UL

3

Assessment Observations Sequence

(0082,0007)

SQ

%item

>Observation Significance

(0082,0008)

CS

MAJOR

>Observation Basis Code Sequence

(0082,0022)

SQ

%item

>>Code Value

(0008,0100)

SH

121375

>>Coding Scheme Designator

(0008,0102)

SH

DCM

>>Code Meaning

(0008,0104)

LO

Assessment By Comparison

%enditem

%endsq

(>Assessment Basis Code Sequence)

>Observation Description

(0082,000A)

UT

Attribute value of Leaf/Jaw Positions is not equal.

>Structured Constraint Observation Sequence

(0082,000C)

SQ

%item

>>Selector Attribute Name

(0082,0018)

LO

Leaf/Jaw Positions

>>Selector Attribute VR

(0072,0050)

CS

DS

>>Selector Attribute

(0072,0026)

AT

300A011C

>>Selector Value Number

(0072,0028) )

US

1

>>Selector Sequence Pointer

(0072,0052)

AT

300A00B0\300A0111\300A011A

>>Selector Sequence Pointer Items

(0074,1057)

IS

1\2\2

>>Constraint Type

(0082,0032)

CS

EQUAL

>>Constraint Violation Significance

(0082,0036)

CS

FAILURE

>>Constraint Value Sequence

(0082,0034)

SQ

%item

>>>Selector DS Value

(0072,0072)

DS

-75.000\75.000

%enditem

%endsq

(>>Constraint Value Sequence)

>>Assessed Attribute Value Sequence

(0082,0010)

SQ

%item

>>>Selector DS Value

(0072,0072)

DS

-75.000

%enditem

%endsq

(>>Assessed Attribute Value Sequence)

%enditem

%endsq

(>Constraint Observation Sequence)

%enditem

%item

>Observation Significance

(0082,0008)

CS

MAJOR

>Observation Basis Code Sequence

(0082,0022)

SQ

%item

>>Code Value

(0008,0100)

SH

121376

>>Coding Scheme Designator

(0008,0102)

SH

DCM

>>Code Meaning

(0008,0104)

LO

Assessment By Quality Rules

%enditem

%endsq

(>Assessment Basis Code Sequence)

>Observation Description

(0082,000A)

UT

Monitor Units re-calculation failed. The re-calculation of the beam meterset resulted in a different value (76MU) than the value in the assessed RT Plan. This value is outside the tolerance of reasonable differences acceptable on re-calculation.

>Structured Constraint Observation Sequence

(0082,000C)

SQ

%item

>>Selector Attribute Name

(0082,0018)

LO

Beam Meterset

>>Selector Attribute VR

(0072,0050)

CS

DS

>>Selector Attribute

(0072,0026)

AT

300A0086

>>Selector Value Number

(0072,0028) )

US

1

>>Selector Sequence Pointer

(0072,0052)

AT

300A0070\300C0004

>>Selector Sequence Pointer Items

(0074,1057)

IS

1\1

>>Constraint Type

(0082,0032)

CS

RANGE_INCL

>>Constraint Violation Significance

(0082,0036)

CS

FAILURE

>>Constraint Value Sequence

(0082,0034)

SQ

%item

>>>Selector DS Value

(0072,0072)

DS

68

%enditem

%item

>>>Selector DS Value

(0072,0072)

DS

84

%enditem

%endsq

(>>Constraint Value Sequence)

>>Assessed Attribute Value Sequence

(0082,0010)

SQ

%item

>>>Selector DS Value

(0072,0072)

DS

108

%enditem

%endsq

(>>Assessed Attribute Value Sequence)

%enditem

%endsq

(>Constraint Observation Sequence)

%enditem

%item

>Observation Significance

(0082,0008)

CS

MODERATE

>Observation Basis Code Sequence

(0082,0022)

SQ

%item

>>Code Value

(0008,0100)

SH

121376

>>Coding Scheme Designator

(0008,0102)

SH

DCM

>>Code Meaning

(0008,0104)

LO

Assessment By Quality Rules

%enditem

%endsq

(>Observation Basis Code Sequence)

>Observation Description

(0082,000A)

UT

The Beam Dose value of all Beams is zero, but Beam Meterset is non-zero.

%enditem

%endsq

(Assessment Observations Sequence)


DICOM PS3.17 2019a - Explanatory Information