双能量CT在胃癌虚拟平扫应用的初步探讨  

Stomach Virtual Non-enhanced CT with Dual-energy CT: A Preliminary Study

作　　者：石磊[1] 张欢[1] 潘自来[1] 刘欢欢[1] 李向亭[2] 杜联军[1] 丁蓓[1] 宋琦[1] 凌华威[1] 陈克敏[1] 严福华[1] 

机构地区：[1]上海交通大学附属瑞金医院放射科 [2]上海交通大学物理系

出　　处：《中国医学计算机成像杂志》2013年第1期33-37,共5页Chinese Computed Medical Imaging

基　　金：国家自然科学基金No.81272746;上海教委基金赞助项目(编号10YE37);上海交通大学医工交叉基金No.YG2012MS48~~

摘　　要：目的:比较胃癌患者术前行双能CT扫描的常规平扫及虚拟平扫图像,评估通过去除常规平扫来降低辐射剂量问题。方法:74例患者行胃双能CT扫描,测量病灶在虚拟平扫和常规平扫图像中的平均CT值、大小、图像质量和有效放射剂量,并进行比较。结果:在常规和虚拟平扫图像中胃癌的最大厚度和肿大淋巴结的最大直径均无显著意义(P>0.05)。在两者图像中所测组织的平均CT值除主动脉外具有显著差异(P<0.05),但绝对值差异值在10HU以下。在动脉期和门脉期的虚拟平扫图像中除主动脉外其他测量的组织CT值无统计学差异(P>0.05)。虚拟平扫图像的噪声较常规平扫图像低(P<0.01)。虚拟平扫图像可以对疾病进行诊断,但是图像质量较常规平扫低(P<0.01)。省去常规平扫所降低的放射剂量是21.40%±4.44%。结论:虚拟平扫在胃癌术前分期扫描中具有代替常规平扫的潜在应用价值,并能因此降低辐射剂量。Purpose： To compare the image quality of true non-enhanced （TNE） and virtual nonenhanced （VNE） image data sets in patients who underwent gastric preoperative dual-energy CT （DECT） and to evaluate potential radiation dose reduction by omitting a TNE scan. Methods： A total of 74 patients underwent gastric DECT. The mean CT values, length, image quality and effective radiation doses for VNE and TNE images were compared. Results： There was no statistical significant difference in maximal thickness of gastric tumors and maximal diameter of enlarged lymph nodes among the TNE and VNE images （p〉0.05）. The mean CT value differences between TNE and VNE were with statistical significant for all tissue types, except for aorta attenuation measurements （P〈0.05）, but the absolute differences were under 10 HU. There was no difference among the VNE images derived from the arterial and portal venous phases （P〉0.05）. Lower noise was found for VNE images than that for TNE diagnosis requirement but lower than that of TNE （P〈 0.01）. images （P〈 0.01）. Image quality of VNE met the The dose reduction achieved by omitting the TNE acquisition was 21.40±4.44%. Conclusion： VNE scan may potentially replace TNE as part of a multi-phase gastric preoperative staging imaging protocol with consequent saving radiation dose.

关 键 词：双能CT 虚拟平扫 胃癌 辐射剂量 

分 类 号：R735.2[医药卫生—肿瘤]