The NOVO project neutron detection for real-time range verification in proton therapy, A Monte Carlo feasibility study

TL;DR

This study proposes a simple neutron detection method using a hydrogen-rich converter and tracking detectors to estimate proton beam range in real-time during therapy, aiming to improve treatment precision.

Contribution

It introduces a novel, Monte Carlo validated neutron detection concept for real-time proton range verification in therapy, enhancing accuracy over existing methods.

Findings

Feasibility of the detector concept demonstrated through Monte Carlo simulations.

Potential for millimetric precision in real-time proton range verification.

The method correlates neutron production depth with primary proton range.

Abstract

Uncertainties in the proton range in tissue during proton therapy limit the precision in treatment delivery. These uncertainties result in expanded treatment margins, thereby increasing radiation dose to healthy tissue. Real-time range verification techniques aim to reduce these uncertainties in order to take full advantage of the finite range of the primary protons. In this paper, we propose a novel concept for real-time range verification based on detection of secondary neutrons produced in nuclear interactions during proton therapy. The proposed detector concept is simple; consisting of a hydrogen-rich converter material followed by two charged particle tracking detectors, mimicking a proton recoil telescopic arrangement. Neutrons incident on the converter material are converted into protons through elastic and inelastic (n,p) interactions. The protons are subsequently detected in the tracking detectors. The information on the direction and position of these protons is then utilized in a new reconstruction algorithm to estimate the depth distribution of neutron production by the proton beam, which in turn is correlated with the primary proton range. In this paper, we present the results of a Monte Carlo feasibility study and show that the proposed concept could be used for real-time range verification with millimetric precision in proton therapy.