双源CT双能量虚拟平扫在肺癌诊断中的初步研究  

A preliminary Study of Dual-Energy Virtual Non-Contrast CT of Dual Source CT in the Diagnosis of Lung Cancer

作　　者：刘江勇[1,2] 王荣品[2] 骆科进[1] 

机构地区：[1]遵义医学院附属医院放射科,563003 [2]贵州省人民医院放射科,贵阳550002

出　　处：《临床放射学杂志》2016年第9期1367-1371,共5页Journal of Clinical Radiology

摘　　要：目的探讨双源CT双能量虚拟平扫(VNC)技术在肺癌诊断中的价值。方法对50例疑似肺癌患者行常规CT平扫和双能量CT增强扫描。观察50例患者常规CT平扫图像与VNC图像,测量降主动脉、左心房及胸椎椎体后方肌肉的平均CT值,计算信噪比(SNR),评价图像质量。使用Liver VNC软件程序获得肿块的VNC CT值及增强净增值。以CT值净增值≥20 HU为诊断肺癌的标准,对本组50例患者进行评价,计算诊断准确率。比较常规扫描与双能量扫描患者辐射剂量。结果 50例患者降主动脉的常规CT平扫与VNC平均CT值差异有统计学意义(P<0.05);左心房及胸椎椎体后方肌肉平均CT值差异无统计学意义(P>0.05)。常规平扫与VNC降主动脉、左心房及胸椎椎体后方肌肉的SNR差异有统计学意义(P值<0.05)。常规平扫图像与VNC图像的质量评分平均得分无统计学意义。以净增值≥20 HU诊断肺癌为标准,34例经过最终病理证实为肺癌的病灶CT值的净增值为(38.69±18.3)HU,准确率为94.1%(32/34);其余16例病灶CT值的净增值为(11.38±9.52)HU,假阳性率为6.25%(1/16)。比较常规扫描与双能量扫描辐射剂量,虽然VNC的CTDIvol、DLP、ED均稍高于常规平扫,差异具有统计学意义(P<0.05),但运用VNC技术节省一次常规平扫剂量,平均每例患者可减少2.29 m Sv有效剂量。结论双源CT双能量VNC技术应用于胸部扫描,可有效降低辐射剂量,并能确保图像质量满足临床诊断要求,在肺癌的诊断中具有较高的应用价值。Objective To investigate the value of dual-energy virtual non-contrast（ VNC） of dual source computed tomography（ DSCT） in the diagnosis of lung cancer. Methods 50 cases of patients suspected with lung cancer underwent conventional plain scan and dual energy enhanced scan. The image qualities of conventional plain scan and VNC of the patients were retrospectively evaluated. The mean CT values and the signal to noise ratio（ SNR） of descending aorta,left atrium and muscles were measured. The image qualities of conventional plain scan were evaluated as a reference. The average CT values of tumor on enhanced images and virtual non-contrast images were compared by using Liver VNC processing unit. The net added CT value of tumor≥20 HU was set as a diagnostic standard of lung cancer,and the diagnostic accuracy was compared with 50 cases of this group. The radiation doses were evaluated between conventional plain scan and virtual dual-energy scan. Results Of the 50 cases of patients,the mean CT values of descending aorta between conventional plain scan and VNC scan was statistically significant（ P〈0. 05）. No significant differences were found between conventional plain scan and VNC scan for the mean CT values of the left atrium and the muscles,（ all P〉0. 05）. There were significant differences in conventional plain scan and VNC scan for SNR of the descending aorta,left atrium and muscles,（ all P〉0. 05）. No significant difference was found in conventional plain scan and VNC scan for the average scores of image quality（ P〉0. 05）. Provided that the net added CT value of tumors≥20 HU as a diagnostic standard of lung cancer,for the pathologically confirmed 34 cases of lung cancer,the net added CT value of tumors was 38. 69 ± 18. 3 HU,the accuracy was 94. 1%（ 32 /34）,and the rest 16 cases,the net added CT value of tumors was（ 38. 69 ± 18. 3） HU and the false positive rate was 6. 25%（ 1 /16）. The radiation doses between conventional plain scan and dual-energy scan were sta-ti

关 键 词：肺癌 体层摄影术 X 线计算机 虚拟平扫 辐射剂量 

分 类 号：R734.2[医药卫生—肿瘤]