DOSE DISTRIBUTION MEASUREMENT DEVICE

摘要

A dose distribution measurement device includes at least two cameras arranged on a plane perpendicular to the center axis of irradiation of a water phantom with a particle beam so as to take an image of light emission of a fluorescent substance containing liquid in the water phantom and a dose distribution calculation and evaluation unit having a spot position determination part for determining, from data of the camera image taken with the cameras, the position of a spot Irradiated with the particle beam during its staying and a dose addition part for calculating an irradiation dose distribution at the spot position determined by the spot position determination part using a PDD and an OCR stored in a pencil-beam dose-distribution data storage part, to add the irradiation dose distribution at each of spot positions.

主权项

1. A dose distribution measurement device for measuring an irradiation dose distribution to be generated when an irradiation-related device for irradiating an irradiation target with a particle beam as a pencil beam irradiates a three-dimensional target region with the particle beam by scanning, every time an energy level of the particle beam is changed, the particle beam over a two dimensional region of the irradiation target at a depth position corresponding to the energy level with repetition of staying and shifting of the particle beam in a two-dimensional direction perpendicular to the beam traveling direction, the dose distribution measurement device comprising:
a water phantom having a fluorescent substance containing liquid that emits light by being irradiated with the particle beam and provided with an incident window for incident of the particle beam; at least two cameras arranged outside the water phantom and on a plane perpendicular to an irradiation center axis in the water phantom, of the particle beam so as to take images of light emission of the fluorescent substance containing liquid; and a dose distribution calculation and evaluation unit including:
a camera image processing part processing the images taken with the at least two cameras;a camera calibration-parameter storage part storing camera calibration parameters for each of the at least two cameras;a spot position determination part determining a position of a spot irradiated with the particle beam during staying of the particle beam, from camera image data processed by the camera image processing part using the camera calibration parameters for each camera which are stored in the camera calibration-parameter storage part;a pencil-beam dose-distribution data storage part storing PDD data and OCR data of the pencil beam; anda dose addition part calculating an irradiation dose distribution at the spot position determined by the spot position determination part using the PDD data and the OCR data stored in the pencil-beam dose-distribution data storage part and adding the irradiation dose distribution at each of spot positions.