辐射研究与辐射工艺学报2026，Vol.44Issue(3)：56-66,11.DOI:10.11889/j.1000-3436.2026-0001
基于多层硅像素芯片的质子断层辐射成像研究
Proton tomography based on multi-layer pixel sensor
摘要
Abstract
To address the range uncertainty in proton therapy arising from the conversion of hounsfield units(HU)to relative stopping power(RSP)in conventional X-ray CT,this study proposes and constructs a high-resolution proton computed tomography(pCT)detection system based on multi-layer silicon pixel detectors.By using the Geant4 Monte Carlo platform,the tomographic imaging process of a 230 MeV clinical proton pencil beam was simulated with a radial scanning step of 0.1 mm.Performance evaluations regarding RSP accuracy and image quality were conducted using the Catphan 600 series phantom.The results indicate that the system exhibits excellent linear response characteristics in measuring the RSP of 7 materials in CTP404 module with varying densities(R2=0.999 72).Through linear calibration,RSP reconstruction deviations for various tissue-equivalent materials—including bone-equivalent material(RSP≈1.84)—were maintained within 1%.In validation tests using a human tissue-equivalent phantom(customized CTP515 module),the system successfully distinguished between muscle and lens tissues with a density difference of only～2%,demonstrating superior low-contrast resolution.Analysis of the high-resolution line-pair module(CTP528)revealed that,under the straight-line path assumption,multiple Coulomb scattering(MCS)effects induced an attenuation of approximately 38.4%in high-frequency signal amplitude,resulting in a modulation transfer function(MTF)of 10%at approximately 5 lp/cm.This study not only validates the technical feasibility of the multi-layer pixel detector architecture for achieving sub-millimeter,iso-source image-guided proton therapy,but also establishes a high-precision RSP quantification workflow that provides core algorithmic support and a viable solution for further reducing range uncertainty in proton therapy.关键词
质子治疗/图像引导/像素探测器/相对阻止能力Key words
Proton therapy/Image guidance/Pixel detector/Relative stopping power分类
医药卫生引用本文复制引用
王宏凯,侯露,冉虎,朱珏琦,祁润奕,陈轶伦,李明辉,张洪林,牛传猛..基于多层硅像素芯片的质子断层辐射成像研究[J].辐射研究与辐射工艺学报,2026,44(3):56-66,11.基金项目
国家自然科学基金(12475314)、中央高水平医院临床科研业务费资助(2025-LYZX-R-B02) Supported by National Natural Science Foundation of China(12475314),and National High Level Hospital Clinical Research Funding(2025-LYZX-R-B02) （12475314）
