DICOM PS3.3 2021a  Information Object Definitions 

The Radiation Fraction Pattern Macro specifies the intended fraction pattern to be used to deliver the radiation treatment.
Table C.36.2.1.11. Radiation Fraction Pattern Macro Attributes
The Radiation Fraction Pattern describes the intended scheme, i.e., how fractions are to be distributed along calendar days for the actual radiation set.
Examples of Fraction Patterns:
1 fraction per day (Monday to Friday) , no fractions on Saturday and Sunday, 1 weekpattern:
Number of Fraction Pattern Digits Per Day (300A,0079) = 1
2 fractions per day (Monday to Friday) , no fractions on Saturday and Sunday 1 weekpattern:
Number of Fraction Pattern Digits Per Day (300A,0079) = 2
1 fraction per day (Monday, Wednesday, Friday) , no fractions on Saturday and Sunday 1 weekpattern:
Number of Fraction Pattern Digits Per Day (300A,0079) = 1
2 fractions per day (Monday, Wednesday, Friday) , one fraction on Saturday morning and Sunday afternoon 1 weekpattern:
Number of Fraction Pattern Digits Per Day (300A,0079) = 2
1 fraction per day every other day 2 weekpattern:
Number of Fraction Pattern Digits Per Day (300A,0079) = 1
The Intended Start Day of Week (3010,0086) specifies the day(s) of the week, when the first fraction of the treatment should be delivered. If more than one day is specified, one of the days may be selected to start the treatment.
The treatment then continues as specified in Fraction Pattern (300A,007B), irrespective of when the actual delivery starts.
Examples of Intended Start Day of Week and the relation to Fraction Pattern:
1 Start Day, one fraction per day
The treatment should start on Wednesday and be continued at Friday of the first week, followed by treatments at Monday, Wednesday, Friday the next week etc., until all fractions are delivered.
Number of Fraction Pattern Digits Per Day (300A,0079) = 1
Repeat Fraction Cycle Length (300A,007A) = 1
Start of any of 3 days, two fractions per day
The treatment will continue the next week with 2 fractions on Monday, Wednesday, Friday etc. until all fractions are delivered.
Number of Fraction Pattern Digits Per Day (300A,0079) = 1
Repeat Fraction Cycle Length (300A,007A) = 2
The treatment phase Macro contains the identification and additional information about an RT Treatment Phase.
Table C.36.2.1.21. RT Treatment Phase Macro Attributes
The Intended Phase Start Date (3010,004C) and Intended Phase End Date (3010,004D) contains the date when this treatment phase is intended to be started or completed. Do not confuse the content of this Attribute with the date when the treatment delivery is scheduled or when it actually starts or ends. The scheduled date is managed by workflow systems where definitive treatment session scheduling is maintained. The actual date of performed delivery will be available in the RT Radiation Record Instances. The actual dates may differ from the Intended Phase Start Date (3010,004C) and/or Intended Phase End Date (3010,004D).
The RT Treatment Phase Interval Macro contains the information about timerelationship between RT Treatment Phases. This consists of sets of pairwise relationships, declaring the relation of a earlier phase to a later, potentially overlapping, phase.
Table C.36.2.1.31. RT Treatment Phase Interval Macro Attributes
Intervals between treatment phases. Zero or more Items shall be included in this Sequence. See Section C.36.2.1.3.2. 

The RT Treatment Phase which provides the basis for this interval. This index corresponds to an Item in the Intended RT Treatment Phase Sequence (3010,004B). See Section C.36.2.1.3.1. 

The RT Treatment Phase which is related to the phase identified by Basis RT Treatment Phase Index (3010,003E). Each RT Treatment Phase Index value shall appear in this Attribute in only one Item within this Sequence. This index corresponds to an Item in the Intended RT Treatment Phase Sequence (3010,004B). See Section C.36.2.1.3.1. 

The anchor point of the interval specified in this Item with respect to the phase referenced by the Basis RT Treatment Phase Index (3010,003E). Enumerated Values: Required if a value is present in Minimum Number of Interval Days (3010,0050) or Maximum Number of Interval Days (3010,0051). 

The minimum number of days that the start of the related phase should follow the basis phase referenced in Basis RT Treatment Phase Index (3010,003E). Fractional values are allowed. Negative values are allowed if Temporal Relationship Interval Anchor (3010,004F) has a value of END. 

The maximum number of days that the start of the related phase should follow the basis phase referenced Basis RT Treatment Phase Index (3010,003E). Fractional values are allowed. Negative values are allowed if Temporal Relationship Interval Anchor (3010,004F) has a value of END. 
The RT Treatment Phase Interval Sequence (3010,004E) allows the definition of an interval between two treatment phases. RT Treatment Phases referenced by the Basis RT Treatment Phase Index (3010,003E) and the Related RT Treatment Phase Index (3010,003F) are related in terms of the number of days between them. Note that the number of days can also be negative and therefore the related treatment phase could start before the prior treatment phase starts respectively ends.
Each RT Treatment Phase identified by the Related RT Treatment Phase Index (3010,003F) may be related to only one RT Treatment Phase identified by the Basis RT Treatment Phase Index (3010,003E). Therefore, any Basis RT Treatment Phase Index (3010,003E) must only appear once in Related RT Treatment Phase Index (3010,003F) within the Sequence.
See also Section C.36.6.1.4.
As a result of the combinations possible, the maximum number of Items in the RT Treatment Phase Interval Sequence (3010,004E) shall be one less than the number of treatment phases present.
The Dosimetric Objective Macro specifies an intended goal to be used in the definition of the dosimetric plan, for plan optimization etc. Dosimetric Objectives may define limits which affect the dose, such as dose volume constraints, minimum or maximum dose, treatment time or MU limits, and radiobiologic effects.
Dosimetric Objectives, such as dose volume constraints, minimum or maximum dose, etc., can be used to specify dose goals for anatomical or other treatment volumes that are referenced by Conceptual Volumes. Other Dosimetric Objectives can also be used to specify general plan optimization objectives not related to anatomical or other treatment volumes, such as Meterset Minimization, etc.
Table C.36.2.1.41. Dosimetric Objective Macro Attributes
Reference to the SOP Instance that contains the original definition of this Dosimetric Objective identified by Dosimetric Objective UID (3010,006E). Required when the Dosimetric Objective UID (3010,0948) was not issued in the current SOP Instance, but read from another SOP Instance.. 

>Include Table 1011 “SOP Instance Reference Macro Attributes” 

Parameters for the objective identified in Dosimetric Objective Type Code Sequence (3010,006D). 

>Include Table 102 “Content Item Macro Attributes Description” 

Describes the radiobiological effects if any that are taken into account to compute dose. Required if Dosimetric Objective Parameter Sequence (3010,0070) contains a parameter which represents a dose. 

>>Include Table C.36.2.1.51 “Radiobiological Dose Effect Description Macro Attributes” 

Whether the objective must be met by the resulting Radiotherapy treatment plan. Detecting whether or not a Radiotherapy treatment plan has met this Dosimetric Objective and how this situation is handled is out of scope of the Standard. 

Dosimetric Objectives (see Section C.36.6.1.6) are identified by UIDs. These UIDs serve as a key to allow references of Dosimetric Objectives within or across various SOP Instances.
A Dosimetric Objective is described by a type expressed in the Dosimetric Objective Type Code Sequence (3010,006D), and a Sequence of zero or more parameters to quantify the objective within the Dosimetric Objective Parameter Sequence (3010,0070).
Table C.36.2.1.42 specifies the parameters that shall be sent.
Table C.36.2.1.42. Dosimetric Objective Parameters
To describe the objective that a maximum of 30% of the volume can receive 50 Gy or more (V_{50}<=30%), one would use the Dosimetric Objective Type Code Sequence (3010,006D) with code value (130015, DCM, "Maximum Percent Volume at Dose"), with the parameters specified in the Dosimetric Objective Parameter Sequence (3010,0070) as follows:
The Radiobiological Dose Effect Description Macro describes whether dose values are provided as physical dose or effective dose. An effective dose value incorporates adjustments to dose by taking into account the radiobiological effects.
Table C.36.2.1.51. Radiobiological Dose Effect Description Macro Attributes
The calculation of the radiobiological effect may be further described by a specific method.
In Table C.36.2.1.52, if the Effective Dose Calculation Method Category Code Sequence (3010,0003) has the code value specified in the left column, the Context Group for Effective Dose Calculation Method Code Sequence (3010,0004) shall be the one specified in the right column.
Table C.36.2.1.52. Effective Dose Calculation Method Context Groups
Effective Dose Calculation Method Category Code Sequence (3010,0003) 
Context Group for Effective Dose Calculation Method Code Sequence (3010,0004) 

DCID 9538 “Radiation Transportbased Effective Dose Method Modifiers” 

(130127, DCM, "Fractionationbased or temporallybased methods") 
DCID 9539 “Fractionationbased Effective Dose Method Modifiers” 
The Radiation Fraction Pattern Macro specifies the intended fraction pattern to be used to deliver the radiation treatment.
Table C.36.2.1.61. RT Radiation Common Base Macro Attributes
The level of detail of content within this SOP Instance. Enumerated Values:


Whether or not device parameters about actual delivery of treatment to a patient have been recorded. 

Only a single Item shall be included in this Sequence. Required if the SOP Class of the SOP Instance including this Module is not RT Radiation Salvage Record Storage (“1.2.840.10008.5.1.4.1.1.481.17”). May be present otherwise. 

Include Table C.36.2.2.41 “RT Treatment Position Macro Attributes”. 

A set of tolerance values to be applied to parameters used for delivery of the RT Radiation. 

>Include Table C.36.2.2.171 “RT Tolerance Set Macro Attributes”. 

A mode of operation on the treatment machine. Required if a special delivery mode is used for treatment and the SOP Class of the SOP Instance including this Module is not RT Radiation Salvage Record Storage (“1.2.840.10008.5.1.4.1.1.481.17”). May be present otherwise. 

The RT Treatment Technique Code Sequence (3010,0080) describes the treatment technique, i.e., how the radiation beam is shaped and targeted.
The RT Treatment Position Macro describes how the patient is to be positioned with respect to the delivery device for treatment.
The behavior of the machine regarding the patient position between specified Control Points is outside the scope of this Standard. Communicating devices shall agree on this behavior.
The Treatment Machine Special Mode Code Sequence (300A,0635) contains a code, for example, (130341, DCM, "Total Body Irradiation") or (130342, DCM, "Total Skin Irradiation"), which selects a set of vendor and machinespecific parameters that alter the treatment parameters and/or safety constraints.
DICOM PS3.3 2021a  Information Object Definitions 
