Patent ID: 8471222

Claim:
A radiotherapy apparatus control method comprising: calculating a rotational correction amount and a first translational correction amount based on a position and orientation of a first region represented by a radioscopic image of a sample subject having the first region and a second region; and calculating a second translational correction amount based on a position and orientation of the second region represented by the radioscopic: image and the rotational correction amount, wherein the rotational correction amount and the first translational correction amount are calculated so that the first region is arranged at a predetermined region when a couch where the sample subject is arranged makes a rotational movement by the rotational correction amount and the couch is translated by the first translational correction amount, the second translational correction amount is calculated so that the second region is arranged at a predetermined region when the couch where the sample subject is arranged makes a rotational movement by the rotational correction amount and the couch is translated by the second translational correction amount, and the first region is larger than the second region.