Patent ID: 8431907

Claim:
A particle beam treatment device comprising an irradiation nozzle for radiating a particle beam as a pencil beam to a target volume so as to form a spot of the particle beam which is the maximum adsorption region at a position in the depth direction of the target volume which is determined by the energy of the particle beam, and for radiating a particle beam to the target volume by moving the pencil beam in the lateral direction which is perpendicular to the advancing direction so as to move the position of the spot in the lateral direction; a dose monitor which measures the dose of the particle beam which is emitted from the irradiation nozzle; a treatment planning part which sets an irradiation dose set value which is applied to the target volume; a treatment control part having an energy setting controller which sets the energy of the particle beam, a beam scanning controller which controls the irradiation nozzle, and an irradiation dose controller which controls an irradiation dose which is applied to the target volume based on a measurement value of the dose monitor and the irradiation dose set value which is set by the treatment planning part, wherein the treatment planning part stores PDD which is the absorbed dose distribution data in the depth direction, which is prepared in advance, by using the absorbed dose at the reference depth which is a predetermined position and nearer to an incident side of the pencil beam than the position of a Bragg peak as the reference, and the irradiation dose set value which is calculated by using an absorbed dose at the reference depth as the reference is outputted to the irradiation dose controller.