DICOM PS3.3 2021e - Information Object Definitions

C.36.24 RT Radiation Set Delivery Instruction Module

The RT Radiation Set Delivery Instruction Module contains information required by a Treatment Delivery System (TDS) to deliver an external beam radiotherapy treatment.

The Module provides data which are not part of the RT Radiation Set and referenced SOP Instances that were issued at the time of treatment planning. The content does not alter the planned amount and location of dose.

The Module provides data which are specific to the upcoming RT Treatment Session, such as the RT Radiation Set to be delivered, the fraction numbers, information about the continuation of delivery, etc. If more than one RT Radiation Set will be delivered in the upcoming RT Treatment session, treatment delivery of each RT Radiation Set will be specified by a separate instance containing this Module.

Typically, this information is supplied by a Treatment Management System to the TDS when it creates an RT Radiation Set Delivery Instruction SOP Instance so that the TDS does not require any additional information beyond the current RT Treatment Session.

The content of the RT Radiation Set Delivery Instruction Module applies to all or a subset of the RT Radiations specified in the referenced RT Radiation Set.

Table C.36.24-1. RT Radiation Set Delivery Instruction Module Attributes

Attribute Name

Tag

Type

Attribute Description

Referenced RT Radiation Set Sequence

(300A,0702)

1

Reference to a Radiation Set SOP Instance containing the Radiations to which the current SOP Instance applies.

Only a single Item shall be included in this sequence.

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

Treatment Device Identification Sequence

(300A,063A)

2

Identifies the treatment device intended to be used for delivering the RT Radiation.

See C.36.24.1.1.

Zero or one Item shall be included in this Sequence.

>Include Table C.36.2.2.1-1 “Treatment Device Identification Macro Attributes”.

RT Radiation Set Delivery Usage

(300A,079E)

1

The intended usage of the RT Radiation Set.

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).

The Defined Terms are specified in C.36.10.1.1.

RT Radiation Set Delivery Number

(300A,0704)

1C

A number that indicates the RT Treatment Fraction of the referenced RT Radiation Set Instance to be delivered.

Required if RT Radiation Set Delivery Usage (300A,079E) is TREATMENT. May be present otherwise.

See C.36.20.1.2.

Clinical Fraction Number

(300A,0705)

1C

A number that indicates the RT Treatment Fraction to be delivered.

Required if RT Radiation Set Delivery Usage (300A,079E) is TREATMENT. May be present otherwise.

See C.36.20.1.2.

RT Radiation Task Sequence

(300A,0797)

1

Subset of RT Radiations to be delivered and/or to have quality assurance procedures applied.

One or more Items shall be included in this Sequence.

All RT Radiation SOP Instances in the referenced RT Radiation Set shall either be in this Sequence or the Omitted Radiation Sequence (300A,0787). Correspondingly the sum of the number of Items in this Sequence and the number of Items in the Omitted Radiation Sequence (300A,0787) shall be the number of RT Radiation SOP Instances in the referenced RT Radiation Set.

If a complete fraction (no continuation of a previously interrupted treatment) is to be delivered, the number of Items in the Sequence shall be the number of RT Radiation SOP Instances in the referenced RT Radiation Set. The Omitted Radiation Sequence (300A,0787) will not be present in this case.

Note

The number of RT Radiation SOP Instances in the referenced RT Radiation Set is the number of SOP Instances contained in the Referenced RT Radiation Sequence (300A,0630) of the Radiation Set SOP Instance referenced in the Referenced RT Radiation Set Sequence (300A,0702).

>Referenced RT Radiation Sequence

(300A,0630)

1

Reference to a single RT Radiation SOP Instance containing the parameters to be used for the delivery of the RT Radiation.

The reference shall contain an RT Radiation SOP Instance that has been referenced in the RT Radiation Set SOP Instance in the Referenced RT Radiation Set Sequence (300A,0702).

Only a single Item shall be included in this sequence.

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

>RT Delivery Start Patient Position Sequence

(300A,0789)

2

The position of the patient at the start of delivery of the RT Radiation referenced in the RT Radiation Sequence (300A,0630).

The content of this Sequence shall take precedence over the treatment positions specified in the referenced RT Radiation.

Zero or one Item shall be included in this Sequence.

>>Include Table C.36.2.3.2-1 “RT Patient Position Macro Attributes”.

>Treatment Delivery Continuation Flag

(300A,0708)

1

Whether the task defines a continuation of a previously interrupted treatment delivery of the referenced RT Radiation.

Enumerated Values:

YES

The task represents a continuation.

NO

The task represents a treatment delivery that starts at the first RT Control Point.

>Continuation Start Meterset

(0074,0120)

1C

Meterset within the RT Radiation referenced in the Referenced RT Radiation Sequence (300A,0630) at which treatment delivery starts.

The Meterset is expressed in units specified by Radiation Dosimeter Unit Sequence (300A,0658) in the referenced RT Radiation SOP Instance.

Required if Treatment Delivery Continuation Flag (300A,0708) is YES.

>Continuation End Meterset

(0074,0121)

1C

Meterset within the RT Radiation referenced in the Referenced RT Radiation Sequence (300A,0630) at which treatment delivery ends.

The Meterset is expressed in units specified by Radiation Dosimeter Unit Sequence (300A,0658) in the referenced RT Radiation SOP Instance.

Required if Treatment Delivery Continuation Flag (300A,0708) is YES and the Continuation End Meterset (0074,0121) is not equal to the Meterset of the last RT Control Point in the referenced RT Radiation SOP Instance.

>Radiation Order Index

(300A,0786)

2

Index defining the order in which the RT Radiations are to be delivered.

The value shall start at 1, and increase monotonically by 1.

>Referenced RT Treatment Preparation Sequence

(300A,078B)

2

Reference to a RT Treatment Preparation SOP Instance that applies to this delivery.

Only a single Item shall be included in this Sequence.

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

>Include Table 10-28 “Device Motion Control Macro Attributes”.

Omitted Radiation Sequence

(300A,0787)

1C

Subset of RT Radiations that are not to be delivered.

The delivery system shall not deliver any RT Radiations referenced in this Sequence.

Required if one or more RT Radiation SOP Instances contained in the referenced RT Radiation Set are not to be delivered.

One or more Items shall be included in this Sequence.

>Referenced RT Radiation Sequence

(300A,0630)

1

The RT Radiation SOP Instance that is not to be delivered.

The reference shall contain an RT Radiation SOP Instance that has been referenced in the RT Radiation Set SOP Instance in the Referenced RT Radiation Set Sequence (300A,0702).

Only a single Item shall be included in this sequence.

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

>Reason for Omission Code Sequence

(300A,0788)

1

Reason the RT Radiation is not to be delivered.

Only a single Item shall be included in this sequence.

>>Include Table 8.8-1 “Code Sequence Macro Attributes”.

DCID 9576 “Reasons for RT Radiation Treatment Omission”.

>Asserter Identification Sequence

(0044,0103)

1

The person or device making the assertion that the RT Radiation is omitted.

Only a single Item shall be included in this sequence.

>>Include Table C.17-3b “Identified Person or Device Macro Attributes”.

Organizational Role BCID 9562 “Radiotherapy Treatment Delivery Person Roles”.

>Reason for Omission Description

(300C,0113)

3

User-defined description of why the RT Radiation is not to be delivered.


C.36.24.1 Radiation Set Delivery Attribute Description

C.36.24.1.1 Treatment Device Identification Sequence

The RT Radiation Set Delivery Instruction Module may specify a treatment device to be used for radiation delivery. This treatment device may differ from the device specified in the referenced RT Radiation Instances.

DICOM PS3.3 2021e - Information Object Definitions