Simulation of an imaging system for internal contamination of lungs using MPA-MURA coded-aperture collimator  

作　　者：Ting Zhang Lei Wang Jing Ning Wei Lu Xiao-Fei Wang Hai-Wei Zhang Xian-Guo Tuo 

机构地区：[1]Chengdu University of Technology,Chengdu 610059,China [2]Sichuan University of Science&Engineering,Zigong 643000,China [3]Beijing Institute of Radiation Medicine,Beijing 100850,China

出　　处：《Nuclear Science and Techniques》2021年第2期58-69,共12页核技术（英文）

基　　金：the Ministry of Science and Technology,People’s Republic of China(No.2012YQ180118);the National Natural Science Foundation of China(No.41874121);the Sichuan Science and Technology Program(No.2018JY0181).

摘　　要：The nuclides inhaled during nuclear accidents usually cause internal contamination of the lungs with low activity.Although a parallel-hole imaging system,which is widely used in medical gamma cameras,has a high resolution and good image quality,owing to its extremely low detection efficiency,it remains difficult to obtain images of inhaled lung contamination.In this study,the Monte Carlo method was used to study the internal lung contamination imaging using the MPA-MURA coded-aperture collimator.The imaging system consisted of an adult male lung model,with a mosaicked,pattern-centered,and anti-symmetric MURA coded-aperture collimator model and a CsI(Tl)detector model.The MLEM decoding algorithm was used to reconstruct the internal contamination image,and the complementary imaging method was used to reduce the number of artifacts.The full width at half maximum of the I-131 point source image reconstructed by the MPAMURA coded-aperture imaging reached 2.51 mm,and the signal-to-noise ratio of the simplified respiratory tract source(I-131)image reconstructed through MPA-MURA coded-aperture imaging was 3.98 dB.Although the spatial resolution of MPA-MURA coded-aperture imaging is not as good as that of parallel-hole imaging,the detection efficiency of PMA-MURA coded-aperture imaging is two orders of magnitude higher than that of parallel-hole collimator imaging.Considering the low activity level of internal lung contamination caused by nuclear accidents,PMA-MURA coded-aperture imaging has significant potential for the development of lung contamination imaging.

关 键 词：Lung internal contamination MPA-MURA Monte Carlo MLEM Spatial resolution Detection efficiency 

分 类 号：TL426[核科学技术—核技术及应用] R445[医药卫生—影像医学与核医学]