DICOM PS3.3 2021e - Information Object Definitions

C.36.20 RT Radiation Record Set Module

The RT Radiation Record Set Module contains treatment-modality-independent information about a set of RT Radiation Records.

The RT Radiation Record Set may refer to an RT Radiation Set SOP Instance that has been used to define the treatment delivery. It may also record ad hoc delivery.

Table C.36.20-1. RT Radiation Record Set Module Attributes

Attribute Name

Tag

Type

Attribute Description

Include Table 10.9.2-1, “Extended Content Identification Macro Attributes”

Treatment Session UID

(300A,0700)

1

A unique identifier of the RT Treatment Session to which this Instance belongs.

Referenced RT Radiation Set Sequence

(300A,0702)

1C

The RT Radiation Set that contains the RT Radiation Instance(s) referenced by the Instances of the Referenced RT Radiation Record Sequence (300A,0703).

Required if an RT Radiation Set Instance provided instructions to the treatment delivery system.

Only a single Item shall be included in this Sequence.

>Include Table 10-11, “SOP Instance Reference Macro Attributes”

RT Radiation Set Usage

(300A,0707)

1

A general indication of how the referenced RT Radiation Set was used.

The Defined Terms are specified in Section C.36.10.1.1.

This value may differ from the RT Radiation Set Intent (300A,0637) within the Instance referenced by the Referenced RT Radiation Set Sequence (300A,0702).

See Section C.36.20.1.4.

Referenced RT Radiation Record Sequence

(300A,0703)

1

RT Radiation Record SOP Instance(s) representing the record of the current treatment set that has been delivered.

One or more Items shall be included in this Sequence.

See Section C.36.20.1.1.

>Include Table 10-11, “SOP Instance Reference Macro Attributes”

RT Radiation Set Delivery Number

(300A,0704)

1C

Count of the delivery of the referenced RT Radiation Set as represented by the current SOP Instance.

Required if Referenced RT Radiation Set Sequence (300A,0702) is present and RT Radiation Set Usage (300A,0707) is TREATMENT. May be present otherwise.

See Section C.36.20.1.2.

Clinical Fraction Number

(300A,0705)

1C

Count of the RT Treatment Fractions that have been delivered, irrespective of the RT Radiation Set(s) used.

Required if Referenced RT Radiation Set Sequence (300A,0702) is present and RT Radiation Set Usage (300A,0707) is TREATMENT. May be present otherwise.

See Section C.36.20.1.2.

RT Treatment Fraction Completion Status

(300A,0706)

1

Defines if the current SOP Instance records a complete treatment delivery of a RT Treatment Fraction.

Enumerated Values:

COMPLETE

PARTIAL

See Section C.36.20.1.3.


C.36.20.1 RT Radiation Record Set Attribute Descriptions

C.36.20.1.1 Referenced RT Radiation Record Sequence

All SOP Instances referenced in this Sequence shall be recorded by the same treatment device (specified by the Treatment Device Identification Macro within the RT Delivery Device Common Module).

An RT Radiation Record instance shall be referenced in exactly one RT Radiation Record Set instance.

The Treatment Session UID within the RT Radiation Record Set shall be identical to those in the Referenced RT Radiation Record instances.

The SOP Classes referenced in this Sequence shall contain the following Modules:

C.36.20.1.2 RT Radiation Set Delivery Number and Clinical Fraction Number

The Clinical Fraction Number (300A,0705) tracks the clinical progress of treatment delivery.

It is a counter that represents an ordinal count of deliveries of fractions within a radiotherapy treatment serving a given combination of prescriptions.

When it is used prospectively in instructions, the value indicates the ordinal count of the treatment fraction to be delivered in the upcoming treatment session. When the upcoming delivery of therapeutic radiation is intended to consist of the delivery of a complete RT Radiation Set serving the same combination of RT Prescriptions as the previous fraction, the value is incremented. When the upcoming delivery of therapeutic radiation is intended to resume the delivery of a previously incomplete fraction, the value is not incremented, i.e. the value is the same as that of the resumed fraction.

When it is used retrospectively in recording, the value indicates the ordinal count of the treatment fraction which has been delivered.

The RT Radiation Set Delivery Number (300A,0704) tracks the number of times a fraction specified by the referenced RT Radiation Set Instance has been delivered.

When it is used prospectively in instructions, the value indicates the ordinal count of the treatment to be delivered by a referenced RT Radiation Set Instance. When the upcoming delivery of therapeutic radiation is intended to consist of the delivery of a complete RT Radiation Set, the value for that RT Radiation Set is incremented. When the upcoming delivery of therapeutic radiation is intended to resume the delivery of a previously incomplete fraction, the value is not incremented, i.e. the value is the same as that of the resumed fraction.

When it is used retrospectively in recording, the value indicates the ordinal count of deliveries by a referenced RT Radiation Set Instance.

Note

  1. If the same RT Radiation Set is used for all treatments, the values of RT Radiation Set Delivery Number (300A,0704) and the Clinical Fraction Number (300A,0705) have the same values.

  2. For some adaptive treatment approaches, details of the device parameters may be altered at the treatment session to accommodate the current position and shape of the patient. In this case, a new RT Radiation Set SOP Instance is used for the subsequent RT Treatment Fractions serving the same set of RT Prescriptions and the RT Radiation Set Delivery Number (300A,0704) re-starts at 1.

  3. The Clinical Fraction Number (300A,0705) is continuously incremented to reflect the clinical progress of a therapeutic series of treatments. In the RT Radiation Record Set for the last of the intended RT Treatment Fractions, this value will usually be equal to the Number of Fractions (3010,007D) present in the corresponding RT Prescription(s).

Example

RT Radiation Set P contains RT Radiations A, B; Adapted RT Radiations indicated by (') and (") ; RT Radiation Sets created are P, P' and P''.

Table C.36.20-2. Delivery of Multiple RT Radiation Set Instances

Treatment Session

RT Radiation Set

Delivered RT Radiations

Clinical Fraction Number (300A,0705)

RT Radiation Set Delivery Number (300A,0704)

1

P

A,B

1

1 (of P)

2

P

A,B

2

2 (of P)

3

P'

A',B'

3

1 (of P')

4

P'

A',B'

4

2 (of P')

5

P''

A'',B''

5

1 (of P'')

6

P

A,B

6

3 (of P)


Delivery of a Single RT Radiation Set Instance with Adaptive Treatments

Figure C.36.20-1. Delivery of a Single RT Radiation Set Instance with Adaptive Treatments


C.36.20.1.3 Complete Versus Partial Fraction

When there is an RT Radiation Record Instance present for all of the RT Radiation Instances for this RT Treatment Fraction and they all have a Treatment Delivery Continuation Flag (300A,0708) of NO and have an RT Treatment Termination Status (300A,0714) of NORMAL the value of RT Radiation RT Treatment Fraction Completion Status (300A,0706) shall be COMPLETE. The expression "all of the RT Radiation Instances" refers to the referenced Instances in the RT Radiation Set, to which this current RT Radiation Record Set refers.

Otherwise the value of RT Treatment Fraction Completion Status (300A,0706) shall be PARTIAL.

Example

RT Radiation Set P contains RT Radiations A and B.

RT Radiation Record Sets created are W, X, Y, and Z.

Table C.36.20-3. Delivery of a Single RT Radiation Set Instance with Partial Treatments

Treatment Session

RT Radiation Set

Delivered RT Radiations

Treatment Delivery Continuation Flag (300A,0708)

RT Treatment Termination Status (300A,0714)

RT Radiation Record Set

RT Treatment Fraction Completion Status (300A,0706)

Clinical Fraction Number (300A,0705)

RT Radiation Set Delivery Number (300A,0704)

1

P

A

NO

NORMAL

W

PARTIAL

1

1

B

NO

ABNORMAL

2

P

B

YES

NORMAL

X

PARTIAL

1

1

A

NO

NORMAL

Y

COMPLETE

2

2

B

NO

NORMAL

3

P

A

NO

NORMAL

Z

COMPLETE

3

3

B

NO

NORMAL


C.36.20.1.4 RT Radiation Set Usage

A typical example for different values of RT Radiation Set Usage (300A,0707) in the current RT Radiation Record Set SOP Instance versus in the SOP Instance referenced by the Referenced RT Radiation Set Sequence (300A,0702) is as follows: The treatment defined by the RT Radiation Set SOP Instance, in which RT Radiation Set Usage (300A,0707) has the value TREATMENT, may be sent to the treatment device and applied for quality assurance without a patient being present. In this case, RT Radiation Set Usage (300A,0707) in the current SOP Instance has the value PLAN_QA.

DICOM PS3.3 2021e - Information Object Definitions