Design optimisation of a TOF-based collimated camera prototype for online hadrontherapy monitoring

TLDR

Hadrontherapy offers superior target conformality, but online monitoring of secondary radiation is essential to ensure treatment quality. The study presents a Monte Carlo–based method to optimize a multi‑slit, time‑of‑flight prompt‑gamma camera for clinical use, aiming for a fast, accurate solution that fits clinical workflow. Using Monte Carlo simulations, the authors develop an analytical tool to predict precision for various geometries and propose two camera designs that balance detection efficiency and spatial resolution for proton therapy with active dose delivery.

Abstract

Hadrontherapy is an innovative radiation therapy modality for which one of the main key advantages is the target conformality allowed by the physical properties of ion species. However, in order to maximise the exploitation of its potentialities, online monitoring is required in order to assert the treatment quality, namely monitoring devices relying on the detection of secondary radiations. Herein is presented a method based on Monte Carlo simulations to optimise a multi-slit collimated camera employing time-of-flight selection of prompt-gamma rays to be used in a clinical scenario. In addition, an analytical tool is developed based on the Monte Carlo data to predict the expected precision for a given geometrical configuration. Such a method follows the clinical workflow requirements to simultaneously have a solution that is relatively accurate and fast. Two different camera designs are proposed, considering different endpoints based on the trade-off between camera detection efficiency and spatial resolution to be used in a proton therapy treatment with active dose delivery and assuming a homogeneous target.