摘要
目的 比较基于水等效直径(WED)的体型特异性剂量评估(SSDE_(WED))和基于有效直径(ED)的SSDE_(ED)在估算成人胸腹部CT辐射剂量中的差异。方法 采用德国西门子SOMATOM Definition AS 64排128层CT机对240例成人患者行胸部(161例)、腹部(79例)平扫,按部位分别分为胸部A组左右径(LAT)〈30 cm,B组30 cm≤LAT≤34 cm,C组LAT〉34 cm和腹部A组LAT〈27cm,B组27 cm≤LAT≤32 cm,C组LAT〉32 cm。记录每例患者的CTDIvol值,并计算ED、WED和转换系数fsize,以及患者的SSDE_(ED)和SSDE_(WED)。比较不同LAT组SSDE_(WED)和SSDE_(ED)之间的差异。结果 胸部扫描患者ED与WED、fsize,ED与fsize,WED及SSDE_(ED)与SSDE_(WED)之间差异均有统计学意义(t=-33.12、32.55、28.44,P〈0.05),3组病例间LAT、ED、WED、SSDE_(ED)和SSDE_(WED) 差异均有统计学意义(F=273.67、140.97、77.05、19.87、32.21,P〈0.05);腹部扫描患者ED与WED、fsize,ED与fsize,WED及SSDE_(ED)与SSDE_(WED)之间差异均有统计学意义(t=-24.09、-22.96、22.46,P〈0.05),3组病例间LAT、ED、WED、SSDE_(ED)和SSDE_(WED)差异均有统计学意义(F=123.89、82.17、83.16、52.74、53.62,P〈0.05)。胸部WED较ED降低约12.0%,导致SSDE_(WED)较SSDE_(ED)增加了约11.6%;腹部WED较ED增加了约5.2%,导致SSDE_(WED)较SSDE_(ED)降低了约4.8%,且胸部及腹部3组病例SSDE_(WED)较SSDE_(ED)均随着LAT的增加而增加。结论 WED能够更好地代表患者的体型大小及衰减特性,SSDE_(WED)能够更准确地计算胸腹部CT患者的辐射剂量。
Objective To compare the difference between SSDE_(ED) and SSDE_(WED) in evaluating the radiation dose of adult chest and abdomen CT scans. Methods A total of 240 adult patients were performed CT scan for chest or abdomen by Siemens 128 slice CT (161 cases in chest, 79 cases in abdomen), and they were divided into three groups according to the different left-right (LAT) sizes of chest and abdomen (for chest, group A, LAT〈30 cm;group B, 30 cm≤LAT≤34 cm;group C, LAT〉34 cm;for abdomen, group A, LAT〈27 cm; group B, 27 cm≤LAT≤32 cm; group C, LAT〉32 cm). The images of middle scanning volume were chosen and measured in elliptic ROIs. The ED, WED and conversion coefficient were calculated, and SSDE_(ED) and SSDE_(WED) were calculated by CTDIvol. The difference between SSDE_(ED) and SSDE_(WED) in different LAT groups were compared. Results For chest CT, the difference between ED and WED, fsize, ED and fsize, WED, SSDE_(ED) and SSDE_(WED) had statistical significance(t=-33.118, 32.552, 28.435, P〈0.05). The LAT, ED, WED, SSDE_(ED) and SSDE_(WED) between 3 groups also had significant difference (F=273.67, 140.97, 77.05, 19.87, 32.21, P〈0.05). For abdomen CT, all parameters had statistically significant difference(t=-24.086, -22.960, 22.457, P〈0.05). The LAT, ED, WED, SSDE_(ED) and SSDE_(WED) in 3 groups were obviously different (F=123.89, 82.17, 83.16, 52.74, 53.62, P〈0.05). Compared with ED, the WED in chest decreased by 12.0%, resulting in SSDE_(WED) increasing about 11.6%. The WED in abdomen increased about 5.2%, resulting in SSDE_(WED) decreasing about 4.8%. Conclusions The WED can represent preferably the size and attenuation characteristics of the patient, and the SSDE_(WED) can be used to accurately evaluatethe patient radiation dose in chest and abdomen CT scanning.
作者
袁子龙
王国柱
张照喜
郑丽丽
杜东屏
陈迢
彭伟
邱建峰
刘玉林
Yuan Zilong;Wang Guozhu;Zhang Zhaoxi;Zheng Lili;Du Dongping;Chen Tiao;Peng Wei;Qiu Jianfeng;Liu Yulin(Department of Radiology,Hubei Cancer Hospital,Wuhan 430079,China;Hubei Key Laboratory of Medical Information Analysis&Tumor Diagnosis and Treatment,Wuhan 430079,China;Department of Radiology,Taishan Medical University,Taian 271016,China)
出处
《中华放射医学与防护杂志》
CAS
CSCD
北大核心
2016年第11期852-856,共5页
Chinese Journal of Radiological Medicine and Protection
基金
科技部国家重点专项计划项目(2016YFC0103400)
关键词
有效直径
水等效直径
体型特异性剂量评估
Effective diameter
Water equivalent diameter
Size-specific dose estimate
