3D TRACKING OF AN HDR SOURCE USING A FLAT PANEL DETECTOR

摘要

A method and apparatus are used to compare an intended treatment plan using a radiation source with a delivered plan. This done by arranging markers at known three-dimensional (3D) positions in a detection reference system between a two dimensional radiation detector configured to acquire images generated by radiation emitted by the radiation source and an area where the radiation source is positioned during a treatment. The positions of projections of the markers on an image detected are determined when the radiation source is at a treatment position in an intended treatment plan reference system. A plurality of lines in the detection reference system are calculated, each line being defined by a 3D position of a marker and a 3D position of a corresponding projection of the marker on the detector according to the image. A 3D position of the radiation source in the detection reference system is inferred based on the calculated lines. If no correspondence between the detection reference system and the intended treatment plan reference system is available, the inferred 3D position is matched with the treatment position to extract the correspondence between the detection reference system and the an intended treatment plan reference system. If the correspondence between the detection reference system and the an intended treatment plan reference system is available, the inferred 3D position is compared with the treatment position.