Radiotherapy equipment control device, radiotherapy equipment control method, and program executed by computer for radiotherapy equipment

A radiotherapy equipment control method of controlling radiotherapy equipment in specifying a positon of a specific portion from positions of a plurality of markers in a subject, the radiotherapy equipment control method comprising:

• acquiring reference position information representing a position within the body of the subject at a reference time of each of the specific portion and the plurality of markers, using an image captured at the reference time by the radiotherapy equipment;
• generating refence position information representing a position within the body of the subject at the reference time of a representative point of the plurality of markers from the reference position information of the plurality of markers;
• generating relative position information using a position represented by the reference position information of the representative point as a base point for a position represented by the reference position information of the specific portion;
• acquiring position information of the plurality of markers within the body of the subject at another time different from the reference time, using an image captured at the another time by the radio therapy equipment;
• generating position information of the representative point within the body of the subject at the another time of the plurality of markers from the position information of the plurality of markers;
• generating position information of the specific portion at the another time from the position information of the representative point and the relative position information;
• and
• controlling the radiotherapy equipment so as to deliver therapeutic radiation to the specific portion using the position information of the specific portion at the another time
• wherein:
• the markers are embedded in the vicinity of the specific portion within the subject,
• the reference position information of the representative point specifies a displacement-based or distance-based weight coefficient for each of the plurality of markers and is generated based on the position information of the plurality of markers weighted by the weigh coefficient, and
• the position information of the representative point is generated based on the position information of the plurality of markers weighted by the weight coefficient.

A non-transitory computer-readable storage medium having a program encoded thereon, the program for causing a computer of a radiotherapy equipment control device for controlling radiotherapy equipment in specifying a position of a specific portion from positions of a plurality of markers in a subject to execute:

• a reference position information acquisition process acquiring reference position information representing a position within the body of the subject at a reference time of each of the specific portion and the plurality of markers, using an image captured at the reference time by the radiotherapy equipment;
• a representative point reference position information computation process generating reference position information representing a position within the body of the subject at the reference time of a representative point of the plurality of markers from the reference position information of the plurality of markers;
• a relative position information computation process generating relative position information using a position represented by the reference position information of the representative point as a base point for a position represented by the reference position information of the specific portion;
• a marker position information acquisition process acquiring position information of the plurality of markers within the body of the subject at another time different than the reference time, using an image captured at the another time by the radiotherapy equipment;
• a representative point position information computation process generating position information of the representative point within the body of the subject at the another time of the plurality of markers from the position information of the plurality of markers;
• and
• a specific portion position information computation process generating position information of the specific potion at the another time from the position information of the representative point and the relative position information,
• wherein the radiotherapy equipment is controlled so as to deliver therapeutic radiation to the specific portion using the position information of the specific portion at the another time,
• the markers are embedded in the vicinity of the specific portion within the subject,
• a displacement-based or distance-based weight coefficient for each of the plurality of markers is specified, and the reference position information of the representative point based on the position information of the plurality of markers weighted by the weight coefficient in the representative point reference position information computation process, and
• the position information of the representative point is generated based on the position information of the plurality of markers weighted by the weight coefficient in the representative point position information computation process.