Hi'CT:a pixel sensor-based device for ion tomography  

作　　者：Yi-Lun Chen Hong-Kai Wang Shi-Yu Zhang Hai-Bo Yang Cheng-Xin Zhao 

机构地区：[1]Institute of Modern Physics,Chinese Academy of Sciences,Lanzhou 730000,China [2]Department of Radiation Oncology,National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital,Chinese Academy of Medical Sciences and Peking Union Medical College,Beijing 100021,China [3]School of Nuclear Science and Technology,University of Chinese Academy of Sciences,Beijing 100049,China [4]Advanced Energy Science and Technology Guangdong Laboratory,Huizhou 516003,China

出　　处：《Nuclear Science and Techniques》2023年第7期231-241,共11页核技术（英文）

基　　金：the National Natural Science Foundation of China(Nos.11975292,12205374,U2032209,and 12222512);Beijing Hope Run Special Fund of Cancer Foundation of China(No.LC2021B23);the CAS“Light of West China”Program,the CAS Pioneer Hundred Talent Program,the Guangdong Major Project of Basic and Applied Basic Research(No.2020B0301030008);the National Key Research and Development Program of China(No.2021YFA1601300 and 2020YFE0202002).

摘　　要：Carbon ions,commonly referred to as particle therapy,have become increasingly popular in the last decade.Accurately predicting the range of ions in tissues is important for the precise delivery of doses in heavy-ion radiotherapy.Range uncertainty is currently the largest contributor to dose uncertainty in normal tissues,leading to the use of safety margins in treatment planning.One potential method is the direct relative stopping measurement(RSP)with ions.Heavy-ion CT(Hi′CT),a compact segmented full digital tomography detector using monolithic active pixel sensors,was designed and evaluated using a 430 MeV/u high-energy carbon ion pencil beam in Geant4.The precise position of the individual carbon ion track can be recorded and reconstructed using a 30μm×30μm small pixel pitch size.Two types of customized image reconstruction algorithms were developed,and their performances were evaluated using three different modules of CAT-PHAN 600-series phantoms.The RSP measurement accuracy of the tracking algorithm for different types of materials in the CTP404 module was less than 1%.In terms of spatial resolution,the tracking algorithm could achieve a 20%modulation transfer function normalization value of CTP528 imaging results at 5 lp/cm,which is significantly better than that of the fast imaging algorithm(3 lp/cm).The density resolution obtained using the tracking algorithm of the customized CTP515 was approximately 10.5%.In conclusion,a compact digital Hi'CT system was designed,and its nominal performance was evaluated in a simulation.The RSP resolution and image quality provide potential feasibility for scanning most parts of an adult body or pediatric patient,particularly for head and neck tumor treatment.

关 键 词：Heavy-ion imaging Computed tomography Silicon pixel detectors Monte Carlo Phantoms RADIOTHERAPY IMAGE-GUIDED Tracking 

分 类 号：TL81[核科学技术—核技术及应用] TP391.41[自动化与计算机技术—计算机应用技术] R730.55[自动化与计算机技术—计算机科学与技术]