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| Simulation of X-ray Machine and Correction of Heel Effect Based on MCNP |
| YAN Yong-qiang1,3,WU Jin-jie3,JIN Shang-zhong1,2,ZHAO Rui3 |
1. School of Optical and Electronic Technology, China Jiliang University, Hangzhou, Zhejiang 310018, China
2. Key Laboratory of Zhejiang Province on Modern Measurement Technology and Instrument, Hangzhou, Zhejiang 310018, China; 3. National Institute of Metrology, Beijing 100029, China |
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Abstract In order to modify the anode heel effect of X-ray tube, according to the common parameters of X-ray tube, a simulation model of X-ray machine is established based on MCNP, and a detector array of 169 pixels is built to simulate the intensifying screen of the imaging system of X-ray machine, and the anode heel image of X-ray tube is explored by using the array. The heel effect filter HEF is designed by polynomial fitting and subsection correction method.The area with high illumination of heel effect is corrected. By comparing the flux distribution between the plane filter and HEF, it is found that HEF successfully corrects the range of -12° to 19° in the direction of the axis of the cathode and anode poles to 60% of the intensity without the filter, and the maximum relative error of the flux in this area is less than 3%, achieving a large uniform area. Through the comparative analysis of the simulated imaging, it is found that the X-ray machine modified by HEF greatly improves the resolution ability of the object. The proposed correction method for the specific X-ray tube parameters and the anode heel effect of the imaging array surface has certain practicability and generalization, and has certain reference value for the design and use of the X-ray machine.
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Received: 27 May 2020
Published: 30 June 2022
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［1］王晓庆. 医用X射线机工程师手册 ［M］. 北京:中国医药科技出版社, 2009.
［2］郭永亮, 王明泉, 张俊生,等. 便携式X光机图像降噪复合算法研究 ［J］. 应用光学, 2011, 32(4): 688-692.
Guo Y L, Wang M Q, Zhang J S, et al. Research on composite algorithm of image noise reduction for portable X-ray machine ［J］. Applied optics, 2011,32( 4): 688-692.
［3］李宝良, 柏荣庆, 王亚南, 等. 在用诊断X射线机质量状况 ［J］. 中国医疗器械杂志, 2008, 32(4): 287-289.
Li B L, Bai R Q, Wang Y N, et al. Quality status of in use diagnostic X-ray machines ［J］. Chinese Journal of medical devices, 2008, 32 (4): 287-289.
［4］吕雅竹, 郭彬,李德红, 等. 诊断X射线能谱影响因素的模拟与分析［J］. 计量学报, 2020, 41(8): 1023-1026.
Lü Y Z, Guo B, Li D H, et al. Simulation and Analysis of Factors Affecting Diagnostic X-ray Energy Spectrum ［J］. Acta Metrologica Sinica, 2020, 41(8): 1023-1026.
［5］吕雅竹, 赵瑞,李德红, 等. X射线剂量当量仪校准因子不确定度评估［J］. 计量学报, 2020, 41(9): 1133-1137.
Lü Y Z, Zhao R, Li D H, et al. Uncertainty Evaluation of Calibration Factor for X-ray Dose Equivalent Instrument ［J］. Acta Metrologica Sinica, 2020, 41(9): 1133-1137.
［6］王家伟, 魏鹏,马伯轩, 等. 诊断X射线检测设备半值层测量结果的影响因素［J］. 计量科学与技术,2021, 65(8): 3-6.
Wang J W, Wei P, Ma B X, et al. Main Factors Affecting Measurement Results of the Half-value Layer of Diagnostic X-ray Testing Equipment［J］. Metrology Science and Technology, 2021, 65(8): 3-6.
［7］项安, 梁鲁, 陈瑞焘. X射线管足跟效应的蒙特卡罗模拟与分析 ［J］. 核技术, 2016, 39(6): 060202-1-5.
Xiang A, Liang L, Chen R T. Monte Carlo simulation and analysis of heel effect of X-ray tube ［J］. Nuclear technology, 2016, 39 (6): 060202-1-5.
［8］Mori S, Endo M, Nishizawa K, et al. Prototype heel effect compensation filter for cone-beam CT ［J］. Phys Med Biol, 2005, 50(22): N359-70.
［9］Ng K P, Kwok C S, Tang F H. Monte Carlo simulation of X-ray spectra in mammography ［J］. Physics in Medicine & Biology, 2000, 45(5): 1309-1318.
［10］高峰, 李志. X射线管辐射剂量分布的理论分析与实验测量 ［J］. 物理实验, 2007,27(8): 25-27.
Gao F, Li Z. Theoretical analysis and experimental measurement of radiation dose distribution of X-ray tube ［J］. Physical experiment, 2007,27(8): 25-27.
［11］Leitz W, Axelsson B, Szendr G. Computed Tomography Dose Assessment-A Practical Approach ［J］. Radiation Protection Dosimetry, 1995, 57(1-4): 377-380.
［12］Bhat M, Pattison J, Bibbo G, et al. Off-axis X-ray spectra: A comparison of Monte Carlo simulated and computed X-ray spectra with measured spectra ［J］. Medical Physics, 1999, 26(2): 303.
［13］曹琴琴, 王奇志. 定向辐射X射线管的蒙特卡罗模拟分析 ［J］. 中国辐射卫生, 2013, 22(6): 644-647.
Cao Q Q, Wang Q Z. Monte Carlo simulation analysis of directional radiation X-ray tube ［J］. China radiation health, 2013, 22(6): 644-647.
［14］Fivez C M, Wambacq P, Suetens P, et al. Influence of Heel effect and of nonuniformity of emitted spectra on dual-energy subtraction in computed radiography ［C］//The International Society for Optical Engineering. Proceedings of SPIE.1996:2708.
［15］Spyrou G, Tzanakos G, Nikiforides G, et al. A Monte Carlo simulation model of mammographic imaging with X-ray sources of finite dimensions ［J］. Physics in Medicine & Biology, 2002, 47(6): 917-933.
［16］段小娟, 吴金杰, 杨元第. EGSnrc程序模拟低能X射线光管参数对射线能谱的影响 ［J］. 计量学报, 2011, 32(s1): 51-53.
Duan X J, Wu J J, Yang Y D. Simulation of the influence of low energy X-ray tube parameters on the energy spectrum by EGSnrc program ［J］. Acta Metrologica Sinica, 2011, 32 (s1): 51-3.
［17］李梦石, 吴金杰, 郭思明, 等. 225kV X光机管电压、管电流及固有过滤的研究 ［J］. 计量学报, 2018, 39(s1): 127-130.
Li M S, Wu J J, Guo S M, et al. Research on tube voltage, tube current and inherent filtration of 225kV X ray machine ［J］. Acta metrologica Sinica, 2018, 39 (s1): 127-130.
［18］Mohammad N L. A survey on the accuracy of capnography comparing to chest X-ray in nasogastric tube placement ［J］. Journal of Urmia Nursing & Midwifery Faculty, 2014,7(1):10-18.
［19］陈盘训. 不同金属材料对不同能量X射线衰减系数的实验测量［R］.中国工程物理研究院科技年报, 2002.
［20］Jiang H. Method and system for target angle heel effect compensation:US07020243B2［P］. 2006.
［21］Moallem P, Moallem A. A Real Time Image Processing Algorithm for Cracks Highlighting in Weld X-Ray Video ［J］. Kuwait Journal of Science & Engineering, 2009, 36(2B): 91-105. |
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2022, Vol. 43 
