C.31.3 RT Ion Machine Verification Module

Table C.31-3 specifies the Attributes used to convey the parameters used in external verification of a radiotherapy ion treatment delivery.

Table C.31-3

RT ION MACHINE VERIFICATION MODULE ATTRIBUTES

Attribute Name Tag Description
Ion Machine Verification Sequence (0074,1046) Sequence containing ion machine verification parameters. Zero or one Item shall be included in this sequence.
>Ion Control Point Verification Sequence (0074,104E) Beam control points for current ion treatment beam. Only a single Item shall be included in this sequence.
>>Meterset Rate Set (3008,0045) The specified speed of delivery of the specified dose in units specified by Primary Dosimeter Unit (300A,00B3) in referenced RT Plan per minute.
>>Nominal Beam Energy (300A,0114) Nominal Beam Energy at control point.
>>Beam Limiting Device Position Sequence (300A,011A) Beam limiting device (collimator) jaw or leaf (element) positions. One or more Items shall be included in this sequence.
>>>RT Beam Limiting Device Type (300A,00B8) Type of beam limiting device (collimator). The value of this attribute shall correspond to RT Beam Limiting Device Type (300A,00B8) defined in an item of Beam Limiting Device Sequence (300A,00B6) Enumerated Values: X = symmetric jaw pair in IEC X direction Y = symmetric jaw pair in IEC Y direction ASYMX = asymmetric jaw pair in IEC X direction ASYMY = asymmetric pair in IEC Y direction MLCX = multileaf (multi-element) jaw pair in IEC X direction MLCY = multileaf (multi-element) jaw pair in IEC Y direction
>>>Leaf/Jaw Positions (300A,011C) Positions of beam limiting device (collimator) leaf (element) or jaw pairs in mm in the IEC BEAM LIMITING DEVICE coordinate axis appropriate to RT Beam Limiting Device Type (300A,00B8), e.g. X-axis for MLCX, Y-axis for MLCY. Contains 2N values, where N is the Number of Leaf/Jaw Pairs (300A,00BC) in Beam Limiting Device Sequence (300A,00B6). Values shall be listed in the IEC leaf (element) subscript order 101, 102, ... 1N, 201, 202, ... 2N.
>>Gantry Angle (300A,011E) Gantry angle of radiation source in degrees, i.e. orientation of the IEC GANTRY coordinate system with respect to the IEC FIXED REFERENCE coordinate system.
>>Gantry Rotation Direction (300A,011F) Direction of Gantry Rotation when viewing gantry from isocenter, for segment following Control Point. See C.8.8.14.8. Enumerated Values: CW = clockwise CC = counter-clockwise NONE = no rotation
>>Beam Limiting Device Angle (300A,0120) Beam Limiting Device angle in degrees, i.e. orientation of the IEC BEAM LIMITING DEVICE coordinate system with respect to the IEC GANTRY coordinate system.
>>Beam Limiting Device Rotation Direction (300A,0121) Direction of Beam Limiting Device Rotation when viewing beam limiting device (collimator) from radiation source, for segment following Control Point. See C.8.8.14.8. Enumerated Values: CW = clockwise CC = counter-clockwise NONE = no rotation
>>Patient Support Angle (300A,0122) Patient Support angle in degrees, i.e. orientation of the IEC PATIENT SUPPORT (turntable) coordinate system with respect to the IEC FIXED REFERENCE coordinate system.
>>Patient Support Rotation Direction (300A,0123) Direction of Patient Support Rotation when viewing table from above, for segment following Control Point. See C.8.8.14.8. Enumerated Values: CW = clockwise CC = counter-clockwise NONE = no rotation
>>Table Top Vertical Position (300A,0128) Table Top Vertical position in mm in the IEC TABLE TOP coordinate system. See C.8.8.14.6.
>>Table Top Longitudinal Position (300A,0129) Table Top Longitudinal position in mm in the IEC TABLE TOP coordinate system. See C.8.8.14.6.
>>Table Top Lateral Position (300A,012A) Table Top Lateral position in mm in the IEC TABLE TOP coordinate system. See C.8.8.14.6.
>>Table Top Pitch Angle (300A,0140) Table Top Pitch Angle in degrees, i.e. the rotation of the IEC TABLE TOP coordinate system about the X-axis of the IEC TABLE TOP coordinate system. See C.8.8.25.6.2.
>>Table Top Pitch Rotation Direction (300A,0142) Direction of Table Top Pitch Rotation when viewing the table along the positive X-axis of the IEC TABLE TOP coordinate system, for segment following Control Point. See C.8.8.14.8 and C.8.8.25.6.2. Enumerated Values: CW = clockwise CC = counter-clockwise NONE = no rotation
>>Table Top Roll Angle (300A,0144) Table Top Roll Angle in degrees, i.e. the rotation of the IEC TABLE TOP coordinate system about the Y-axis of the IEC TABLE TOP coordinate system. See C.8.8.25.6.2.
>>Table Top Roll Rotation Direction (300A,0146) Direction of Table Top Roll Rotation when viewing the table along the positive Y-axis of the IEC TABLE TOP coordinate system, for segment following Control Point. See C.8.8.14.8 and C.8.8.25.6.2. Enumerated Values: CW = clockwise CC = counter-clockwise NONE = no rotation.
>>Head Fixation Angle (300A,0148) Angle in degrees of the head fixation for eye treatments with respect to the Table Top Pitch Angle (300A,0140) coordinate system. Positive head fixation angle is the same direction as positive Table Top Pitch. See C.8.8.25.6.4.
>>Gantry Pitch Angle (300A,014A) Gantry Pitch Angle in degrees of the radiation source, i.e. the rotation of the IEC GANTRY coordinate system about the X-axis of the IEC GANTRY coordinate system. See C.8.8.25.6.5.
>>Gantry Pitch Rotation Direction (300A,014C) Direction of Gantry Pitch Angle when viewing along the positive X-axis of the IEC GANTRY coordinate system, for segment following Control Point. See C.8.8.14.8 and C.8.8.25.6.5. Enumerated Values: CW = clockwise CC = counter-clockwise NONE = no rotation
>>Snout Position (300A,030D) Axial position in mm of the snout, measured from isocenter to the downstream side of the snout (without consideration of variable length elements such as blocks, MLC and/or compensators).
>>Range Shifter Settings Sequence (300A,0360) Range Shifter settings for the current control point. One or more Items shall be included in this sequence.
>>>Range Shifter Setting (300A,0362) Machine specific setting attribute for the range shifter. See C.8.8.25.5.
>>>Referenced Range Shifter Number (300C,0100) Uniquely references Range Shifter described by Range Shifter Number (300A,0316) in Range Shifter Sequence (300A,0314).
>>Lateral Spreading Device Settings Sequence (300A,0370) Lateral Spreading Device settings for the current control point. One or more Items shall be included in this sequence.
>>>Lateral Spreading Device Setting (300A,0372) Machine specific setting attribute for the lateral spreading device. See C.8.8.25.5.
>>>Referenced Lateral Spreading Device Number (300C,0102) Uniquely references Lateral Spreading Device described by Lateral Spreading Device Number (300A,0334) in Lateral Spreading Device Sequence (300A,0332).
>>Range Modulator Settings Sequence (300A,0380) Range Modulator Settings for current control point. One or more Items shall be included in this sequence.
>>>Range Modulator Gating Start Value (300A,0382) Start position, defining the range modulator position at which the beam is switched on.
>>>Range Modulator Gating Stop Value (300A,0384) Stop position, defining the range modulator position at which the beam is switched off.
>>>Referenced Range Modulator Number (300C,0104) Uniquely references Range Modulator described by Range Modulator Number (300A,0344) in Range Modulator Sequence (300A,0342).
>>Ion Wedge Position Sequence (300A,03AC) Wedge positions for current control point. One or more Items shall be included in this sequence.
>>>Wedge Thin Edge Position (300A,00DB) Closest distance in mm from the central axis of the beam along a wedge axis to the thin edge as projected to the machine isocentric plane. Value is positive is the wedge does not cover the central axis, negative if it does. See C.8.8.25.6.4.
>>>Wedge Position (300A,0118) Position of Wedge at current Control Point. Enumerated Values: IN OUT
>>Referenced Control Point Index (300C,00F0) Uniquely identifies Control Point specified by Control Point Index (300A,0112 within the Beam referenced by Referenced Beam Number (300C,0006).
>Recorded Snout Sequence (3008,00F0) Snouts associated with Beam. Only a single Item shall be included in this sequence.
>>Accessory Code (300A,00F9) An accessory identifier to be read by a device such as a bar code reader.
>>Snout ID (300A,030F) User or machine supplied identifier for Snout.
>Recorded Range Shifter Sequence (3008,00F2) Range shifters recorded with Beam. Zero or more Items shall be included in this sequence.
>>Accessory Code (300A,00F9) An accessory identifier to be read by a device such as a bar code reader.
>>Range Shifter ID (300A,0318) User or machine supplied identifier for Range Modulator.
>>Referenced Range Shifter Number (300C,0100) Uniquely identifies range shifter specified by Range Shifter Number (300A,0316) within Beam referenced by Referenced Beam Number (300C,0006).
>Recorded Lateral Spreading Device Sequence (3008,00F4) Lateral spreading devices associated with Beam. Zero or more Items shall be included in this sequence.
>>Accessory Code (300A,00F9) An accessory identifier to be read by a device such as a bar code reader.
>>Lateral Spreading Device ID (300A,0336) User or machine supplied identifier for Lateral Spreading Device.
>>Referenced Lateral Spreading Device Number (300C,0102) Uniquely identifies lateral spreading device specified by Lateral Spreading Device Number (300A,0334) within Beam referenced by Referenced Beam Number (300C,0006).
>Recorded Range Modulator Sequence (3008,00F6) Range modulators associated with Beam. Zero or more Items shall be included in this sequence.
>>Accessory Code (300A,00F9) An accessory identifier to be read by a device such as a bar code reader.
>>Range Modulator ID (300A,0346) User or machine supplied identifier for Range Modulator.
>>Range Modulator Type (300A,0348) Type of Range Modulator. See C.31.3.1 for Defined Terms.
>>Beam Current Modulation ID (300A,034C) User-supplied identifier for the beam current modulation pattern.
>>Referenced Range Modulator Number (300C,0104) Uniquely references Range Modulator described by Range Modulator Number (300A,0344) in Range Modulator Sequence (300A,0342).
>Radiation Mass Number (300A,0302) Mass number of radiation.
>Radiation Atomic Number (300A,0304) Atomic number of radiation.
>Radiation Charge State (300A,0306) Charge state of radiation.
>Scan Mode (300A,0308) The method of beam scanning to be used during treatment. Defined Terms: NONE = No beam scanning is performed. UNIFORM = The beam is scanned between control points to create a uniform lateral fluence distribution across the field. MODULATED = The beam is scanned between control points to create a modulated lateral fluence distribution across the field.
>Number of Range Shifters (300A,0312) Number of range shifters associated with current beam.
>Number of Lateral Spreading Devices (300A,0330) Number of lateral spreading devices associated with current beam.
>Number of Range Modulators (300A,0340) Number of range modulators associated with current beam.
>Patient Support Type (300A,0350) Defined terms: TABLE = Treatment delivery system table CHAIR = Treatment delivery system chair See C.8.8.25.6.3.
>Patient Support ID (300A,0352) User-specified identifier for manufacturer specific patient support devices.
>Patient Support Accessory Code (300A,0354) A Patient Support accessory identifier to be read by a device such as a bar code reader.
>Fixation Light Azimuthal Angle (300A,0356) Azimuthal angle in degrees of the fixation light coordinate around the IEC BEAM LIMITING DEVICE Y-axis. Used for eye treatments. See C.8.8.25.6.4.
>Fixation Light Polar Angle (300A,0358) Polar angle in degrees of the fixation light coordinate. Used for eye treatments. See C.8.8.25.6.4.

C.31.3.1 Range Modulator Type

Defined Terms for Range Modulator Type (300A,0348) are as follows:

FIXED = fixed modulation width and weights using ridge filter or constant speed wheel with constant beam current

WHL_FIXEDWEIGHTS = selected wheel/track (Range Modulator ID) is spinning at constant speed. Modulation width is adjusted by switching constant beam current on and off at wheel steps indicated by Range Modulator Interrupt Values

WHL_MODWEIGHTS = selected wheel/track (Range Modulator ID) is spinning at constant speed. Weight per wheel step is adjusted by modulating beam current according to selected Beam Current Modulation ID (300A,034C).