PDF(Pubmed)
Abstract：
UNASSIGNED: Computed tomography (CT) imaging has a large portion in the dose of patients from radiological procedures; therefore, accurate calculation of radiation risk estimation in this modality is inevitable. In this study, a method for determining the patient-specific effective dose using the dose-length product (DLP) index in lung CT scan using Monte Carlo (MC) simulation is introduced.
UNASSIGNED: EGSnrc/BEAMnrc MC code was used to simulate a CT scanner. The DOSxyznrc simulation code was used to simulate a specific voxelized phantom from the patient\'s lungs and irradiate it according to X-ray parameter of routing lung CT scan, and dose delivered to thorax organs was calculated. Three types of phantoms were simulated according to three different body habits (slim, standard, and fat patients) in two groups of men and women. A factor was used to convert the relative dose per particle in MC code to the absolute dose. The dose was calculated in all lung organs, and the effective dose was calculated for all three groups of patient body habits. DLP index and volume CT dose index (CTDIvol) were extracted from the patient\'s dose report in the CT scanner. The DLP to effective dose conversion factor (k-factor) for patients with different body habitus was calculated.
UNASSIGNED: Lung radiation dose in slim, standard, and fat patients in men was 0.164, 0.103, and 0.078 mGy/mAs and in women was 0.164, 0.105, and 0.079 mGy/mAs, respectively. The k-factor in the group of slim patients, especially in women, was higher than in other groups.
UNASSIGNED: CT scan dose indexes for slim patients are reported to be underestimated in studies. The dose report in CT scan systems should be modified in proportion to the patient\'s body habitus, to accurately estimate the radiation risk.
UNASSIGNED: EGSnrc/BEAMnrc MC code was used to simulate a CT scanner. The DOSxyznrc simulation code was used to simulate a specific voxelized phantom from the patient\'s lungs and irradiate it according to X-ray parameter of routing lung CT scan, and dose delivered to thorax organs was calculated. Three types of phantoms were simulated according to three different body habits (slim, standard, and fat patients) in two groups of men and women. A factor was used to convert the relative dose per particle in MC code to the absolute dose. The dose was calculated in all lung organs, and the effective dose was calculated for all three groups of patient body habits. DLP index and volume CT dose index (CTDIvol) were extracted from the patient\'s dose report in the CT scanner. The DLP to effective dose conversion factor (k-factor) for patients with different body habitus was calculated.
UNASSIGNED: Lung radiation dose in slim, standard, and fat patients in men was 0.164, 0.103, and 0.078 mGy/mAs and in women was 0.164, 0.105, and 0.079 mGy/mAs, respectively. The k-factor in the group of slim patients, especially in women, was higher than in other groups.
UNASSIGNED: CT scan dose indexes for slim patients are reported to be underestimated in studies. The dose report in CT scan systems should be modified in proportion to the patient\'s body habitus, to accurately estimate the radiation risk.
摘要：
■计算机断层扫描（CT）成像在放射学程序的患者剂量中占很大比例；因此，在这种模式下，准确计算辐射风险估计是不可避免的。在这项研究中,介绍了一种使用蒙特卡罗（MC）模拟在肺部CT扫描中使用剂量长度乘积（DLP）指数确定患者特定有效剂量的方法。
■EGSnrc/BEAMnrcMC代码用于模拟CT扫描仪。DOSxyznrc模拟代码用于模拟来自患者肺部的特定体素化体模，并根据路由肺部CT扫描的X射线参数对其进行照射，并计算递送至胸部器官的剂量。根据三种不同的身体习惯(苗条，标准,和肥胖患者)两组男性和女性。使用因子将MC代码中每个颗粒的相对剂量转换为绝对剂量。剂量是在所有肺器官中计算的，并计算三组患者身体习惯的有效剂量。从CT扫描仪中患者的剂量报告中提取DLP指数和容积CT剂量指数（CTDIvol）。计算不同体质患者的DLP至有效剂量转换因子(k因子)。
■苗条的肺部辐射剂量，标准,男性肥胖患者为0.164、0.103和0.078mGy/mAs，女性为0.164、0.105和0.079mGy/mAs，分别。苗条患者组中的k因子，尤其是女性,高于其他组。
■据报道，苗条患者的CT扫描剂量指数在研究中被低估。CT扫描系统中的剂量报告应根据患者的身体习惯按比例修改。准确估计辐射风险。
■EGSnrc/BEAMnrcMC代码用于模拟CT扫描仪。DOSxyznrc模拟代码用于模拟来自患者肺部的特定体素化体模，并根据路由肺部CT扫描的X射线参数对其进行照射，并计算递送至胸部器官的剂量。根据三种不同的身体习惯(苗条，标准,和肥胖患者)两组男性和女性。使用因子将MC代码中每个颗粒的相对剂量转换为绝对剂量。剂量是在所有肺器官中计算的，并计算三组患者身体习惯的有效剂量。从CT扫描仪中患者的剂量报告中提取DLP指数和容积CT剂量指数（CTDIvol）。计算不同体质患者的DLP至有效剂量转换因子(k因子)。
■苗条的肺部辐射剂量，标准,男性肥胖患者为0.164、0.103和0.078mGy/mAs，女性为0.164、0.105和0.079mGy/mAs，分别。苗条患者组中的k因子，尤其是女性,高于其他组。
■据报道，苗条患者的CT扫描剂量指数在研究中被低估。CT扫描系统中的剂量报告应根据患者的身体习惯按比例修改。准确估计辐射风险。
