Particle beam therapy system

Abstract

A particle therapy system has an irradiation system attached to a rotary drum of a gantry. A radiation treatment cage disposed in the rotary drum includes a movable floor including a horizontal floor portion. The movable floor includes a number of footboards connected bendably and X-ray transmission plates. The movable floor has a slide member at each end thereof, and the slide member is movably attached to a guide rail that is provided for each of opposite side surfaces of the irradiation system. X-ray sources are disposed outside the rotary drum apart from each other in a circumferential direction of the rotary drum and attached to the outer surface of the rotary drum. The irradiation system includes X-ray detection systems opposite to the X-ray sources.

1 . A particle therapy system comprising:
 a gantry;   an irradiation system which is attached to the gantry and to which an ion beam is incident;   a treatment cage installed in the gantry, having an orbit including an arc-like portion and a horizontal portion communicating with the arc-like portion, and including a surrounding member formed by a plurality of connected footboard members and capable of moving along the orbit;   an X-ray source disposed outside the surrounding member and attached to the gantry; and   an X-ray detection system disposed inside the surrounding member, attached to the irradiation system, and detecting an X-ray from the X-ray source, wherein the surrounding member includes an X-ray transmission member disposed between the adjacent footboard members, connected to the each of the adjacent footboard members, disposed between the X-ray source and the X-ray detection system, and transmitting an X-ray emitted from the X-ray source.   
     
     
         2 . The particle therapy system according to  claim 1 , wherein a width W 2  of the X-ray transmission member in a circumferential direction of the gantry is larger than a width W 1  of the footboard member in the circumferential direction and is less than or equal to a value obtained by subtracting the width W 1  from a width W H  of a horizontal floor portion of the surrounding member that is located in the horizontal portion of the orbit. 
     
     
         3 . The particle therapy system according to  claim 2 , wherein the X-ray transmission member includes an X-ray transmission region and a plate-shaped metal member and a width W 3  of the X-ray transmission region in the circumferential direction is smaller than the width W 2  of the X-ray transmission member. 
     
     
         4 . The particle therapy system according to  claim 1 , wherein:
 the X-ray source is disposed outside the gantry and attached to an outer surface of the gantry; and   an X-ray transmission hole is formed at a position on the gantry opposite to the X-ray source.   
     
     
         5 . The particle therapy system according to  claim 1 , wherein
 the X-ray source includes a first X-ray source and a second X-ray source;   the first X-ray source and the second X-ray source are disposed apart from each other in a circumferential direction of the gantry;   the X-ray detection system includes a first X-ray detection system and a second X-ray detection system;   the first X-ray detection system is disposed opposite to the first X-ray source; and   the second X-ray detection system is disposed opposite to the second X-ray source.   
     
     
         6 . The particle therapy system according to  claim 5 , wherein
 the X-ray transmission member includes a first X-ray transmission member and a second X-ray transmission member;   the first X-ray transmission member is disposed opposite to the first X-ray source; and   the second X-ray transmission member is disposed opposite to the second X-ray source.   
     
     
         7 . The particle therapy system according to  claim 1 , wherein a width W 2  of each of the first and second X-ray transmission members in a circumferential direction of the gantry is larger than a width W 1  of the footboard member in the circumferential direction and is less than or equal to a value obtained by subtracting the width W 1  from a width W H  of the horizontal floor portion of the surrounding member that is located in the horizontal portion of the orbit. 
     
     
         8 . The particle therapy system according to  claim 7 , wherein each of the first and second X-ray transmission members includes an X-ray transmission region and a plate-shaped metal member and a width W 3  of the X-ray transmission region in the circumferential direction is smaller than the width W 2  of the X-ray transmission member. 
     
     
         9 . The particle therapy system according to  claim 1 , further comprising a pair of connectors provided for the irradiation system, the connector connecting between each of opposite ends of the surrounding member and each of a pair of opposite side surfaces of the irradiation system in a manner that movement in a radial direction of the gantry is possible. 
     
     
         10 . The particle therapy system according to  claim 9 , wherein the connector comprises a guide member attached to the side surface of the irradiation system and extending in the radial direction of the gantry, and a slide member attached to the end of the movable floor member and attached movably to the guide member. 
     
     
         11 . The particle therapy system according to  claim 9 , wherein the pair of side surfaces of the irradiation system opposite to each other in the rotating direction of the gantry is tapered toward a center axis of the gantry. 
     
     
         12 . The particle therapy system according to  claim 6 , wherein the surrounding member includes a first movable floor portion including a plurality of footboard members connected bendably and the second X-ray transmission member, and a second movable floor portion including a plurality of footboard members connected bendably and the first X-ray transmission member. 
     
     
         13 . The particle therapy system according to  claim 9 , further comprising a cover that closes an opening generated in the surrounding member, and a cover winding system that moves the cover. 
     
     
         14 . The particle therapy system according to  claim 1 , further comprising an accelerator that accelerates the ion beam, and a beam transport that is connected to the accelerator and guides the ion beam from the accelerator to the irradiation system.