Feasibility Study of Range Verification in Proton Therapy Based on Neutron Information

Proton therapy has been widely used in tumor therapy due to its Bragg peak characteristics. However, the uncertainty of proton range will seriously affect the therapeutic effect. Therefore, it is important to explore the proton real-time range verification technology. In this paper, we investigate the feasibility of range verification based on detection of secondary neutrons produced in nuclear interaction during proton therapy. Firstly, the neutron detection system based on EJ276 plastic scintillator is established, which can detect neutrons from most directions. Then, the energy and flux information of secondary neutrons produced in phantom are simulated and analyzed. The variation of neutron flux is related to proton range. At last, the neutrons direction and position recorded in detector are utilized to trace the neutron emission position to obtain the traced neutron flux distribution (TNFD). The results demonstrated that the distal drop of the TNFD is close to proton range.