Characterization of pixelated silicon detectors for daily quality assurance measurements in proton therapy

TL;DR

This study evaluates pixelated silicon detectors for daily quality assurance in proton therapy, demonstrating their high spatial resolution and potential to streamline measurements with promising initial results.

Contribution

It introduces the application of ATLAS pixelated silicon detectors for proton therapy QA, including dose calibration and energy verification strategies.

Findings

High spatial resolution beam profile measurements

Effective dose-dependent calibration method

Promising initial results at clinical site

Abstract

The advanced imaging and delivery techniques in proton therapy allow conformal high-dose irradiation of the target volume with high accuracy using pencil beam scanning or beam shaping apertures. These irradiation methods increasingly include small radiation fields with large dose gradients, which require detector systems with high spatial resolution for quality assurance. In addition the measurement of all success parameters for daily quality assurance with only one proton field and one simple detector system would save a lot of time in clinical usage. Based on their good spatial resolution and high rate compatibility, pixelated silicon detectors could meet the new requirements. To assess their applicability in proton therapy, ATLAS pixelated silicon detectors are used to measure the lateral beam profile with high spatial resolution. Furthermore, a dose dependent detector calibration is presented to allow the measurement of the requested output constancy. A strategy to verify the proton energy during the daily quality assurance is under study. Promising results from proof-of-principle measurements at the West German Proton Therapy Centre in Essen, Germany, have been obtained.