[3F07-12] Medical Application of Radiations

4:00 PM - 4:15 PM JST(7:00 AM - 7:15 AM UTC)

[3F12] Development of Dose Evaluation System Using a LaBr₃ Detector for Boron Neutron Capture Therapy

*Ziyue Zhu¹, Tatsuya Katabuchi¹, Gengchen Li¹, Risa Kunitomo¹, Zefeng Shao¹, Maxwell Clark Maloney¹ (1. Science Tokyo)

Keywords:

BNCT,PG-SPECT,LaBr3(Ce) detector,Neutron-induced background,PHITS

Prompt-γ-ray SPECT (PG-SPECT) is a promising approach for online dose evaluation in boron neutron capture therapy (BNCT), but it faces several challenges. A major issue is the strong neutron-induced γ-ray background. The high neutron fluence in BNCT leads to extensive neutron interactions within the detection system, generating a complex γ-ray background that interferes with the 478 keV signal from the ¹⁰B(n,a)⁷Li reaction. Another challenge lies in the trade-off between lightweight system and shielding. Detecting the 478 keV γ-ray requires much thicker shielding than conventional low-energy γ-ray SPECT, making compact practical designs difficult. In this study, PHITS simulations are conducted to clarify the origin of neutron-induced γ-ray background and to explore optimized shielding and collimator configurations, supporting the development of a clinically feasible PG-SPECT.