Neutron capture therapy apparatus and neutron beam measuring method

Abstract

There is provided a neutron capture therapy apparatus (1) capable of measuring the neutron dose in real time while suppressing a reduction in the measurement accuracy of a neutron beam (N). A real-time dose output unit (40) including a scintillation detector (41), which detects the neutron beam (N) and outputs a signal in real time, and a neutron dose output unit (44), which converts the signal, output from the scintillation detector (41) into a neutron dose using a correction coefficient (45) and outputs the neutron dose in real time, and a correction coefficient setting unit (60) that sets the correction coefficient 45 are provided. The correction coefficient setting unit (60) includes a gamma ray detection section (62) that detects a gamma ray emitted from a gold wire (61) activated by irradiation of the neutron beam (N), and modifies the correction coefficient (45) based on a signal, which is output from the scintillation detector (41) by irradiation of the neutron beam (N), and a dose of the neutron beam (N), which is acquired based on the gamma ray detected by the gamma ray detection section (62).

Description

technical field [0001] This application claims priority based on Japanese Patent Application No. 2013-108339 filed on May 22, 2013. The entire content of the application is incorporated in this specification by reference. [0002] The present invention relates to a neutron capture therapy device for irradiating a subject to be irradiated with a neutron beam and a method for measuring the neutron beam. Background technique [0003] Boron Neutron Capture Therapy (BNCT: Boron Neutron Capture Therapy) using a boron compound is known as a neutron capture therapy that kills cancer cells by neutron beam irradiation. In boron neutron capture therapy, a drug containing boron is administered to a patient to accumulate boron at a site where cancer cells exist, and the site where the boron is accumulated is irradiated with a neutron beam to kill the cancer cells. [0004] As a neutron capture therapy device used in such neutron capture therapy, Patent Document 1 describes a therapeuti...

AI Technical Summary

Problems solved by technology

However, in scintillation detectors, there is a problem that the detection efficiency of neutron beams gradually decreases due to deterioration of scintillators and optical fibers as the neutron beams are irradiated.

In addition, there is a problem that the gas between the electrodes in the ionization chamber deteriorates due to irradiation of the neutron beam, and the detection efficiency of the neutron beam changes when the gas pressure changes.

If the detection efficiency of the neutron beam changes as described above, the signal state relative to the amount of the actually irradiated neutron beam will gradually change, so there will be a problem that the measurement accuracy of the neutron beam will decrease.

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