Apparatus, method, and program for movable part tracking and treatment

A movable part tracking and treatment apparatus, comprising:

• an image extraction unit adapted to extract an affected part area and a tracing target from a first moving image, the affected part area and the tracing target displaced together in conjunction with a repetitive displacement of respiration, the first moving image acquired by imaging an inside of a body of a patient;
• an analysis unit adapted to compare a repetitive displacement of the affected part area and the tracing target to analyze a phase condition of the tracing target, the phase condition matches with a beam irradiation point selected from displacement of the affected part area;
• a tracing target identification unit adapted to identify the tracing target from a second moving image of the patient imaged after a treatment table having the patient mounted thereon and being moved for aiming the beam irradiation point;
• a phase determination unit adapted to determine whether or not a phase of the tracing target displaced in the second moving image satisfies the phase condition;
• and
• a beam emission unit adapted to emit the beam at a timing when it is determined that the phase condition is satisfied.