中性子捕捉療法における治療効果を評価する即発ガンマ線計測システム

Prompt gamma-ray measurement system for evaluating therapeutic effects in neutron capture therapy

Chiu, I.-H.; 大澤 崇人  

Chiu, I.-H.; Osawa, Takahito

Boron Neutron Capture Therapy (BNCT) is based on the 10B reaction, which produces high energy secondary particles that selectively damage tumor cells. Therefore, accurate evaluation of boron reactions under neutron irradiation is important for dose assessment and treatment verification. Because the boron capture reactions produce a 478 keV prompt gamma-ray with sufficient penetration depth in tissue, detection of this gamma-ray provides spatial information on boron and allows evaluation of the delivered dose. In this study, we developed a prompt gamma-ray measurement system using a CdTe double-sided strip detector (CdTe-DSD) for in situ monitoring. Performance tests were conducted at the Japan Research Reactor-3 (JRR-3) using boron solution phantoms under neutron irradiation conditions. Prompt gamma-rays emitted from boron capture events were successfully detected, and two-dimensional visualization of boron-containing samples was demonstrated. These results indicate the feasibility of CdTe-DSD-based prompt gamma measurements for boron reaction monitoring in BNCT environments.