新双源CT虚拟平扫技术在肝脏检查中的应用  

Virtual non-contrast of liver from dual energy CT： a clinical application

作　　者：钱玉娥[1] 胡红杰[1] 张峭巍[1] 胡鹏[1] 沈国惠[1] 

机构地区：[1]浙江大学医学院附属邵逸夫医院放射科,杭州310016

出　　处：《中华放射学杂志》2011年第2期120-123,共4页Chinese Journal of Radiology

摘　　要：目的研究新双源cT的虚拟平扫技术在肝脏扫描中的应用价值。方法51例肝脏cT平扫和增强扫描患者在完成常规平扫、肝动脉期及门静脉期3期扫描后，采用肝脏虚拟平扫后处理软件生成虚拟平扫图像。采用Wilcoxon分析比较常规平扫和虚拟平扫图像的病灶显示，并利用t检验对比分析肝脏、肌肉的CT值、图像SNR，以及患者单期扫描时接受的辐射剂量和总辐射剂量容积cT剂量指数（CTDIv01）值和剂量长度乘积（DLP）值。结果虚拟平扫和常规平扫在病灶显示上无明显差异。虚拟平扫肝脏cT值（61．32±6．04）HU，大于常规平扫的（56．85±4．80）HU，差异有统计学意义（t=-3．927，P〈0．01）；虚拟平扫图像SNR11．28±2．78，大于常规平扫的8．65±1．56，差异有统计学意义（t=-5．590，P〈0．01）。虚拟平扫CTDIvol总量（14．35±1．66）racy和DLP总量（313．91±45．08）mGy·em均低于常规平扫的（21．43±2．46）mGy和（469．02±66．22）mGy·em，差异均有统计学意义（t值分别为16．168和13．132，P值均〈O．01）。结论新双源cT的虚拟平扫技术在保证图像质量的前提下降低了辐射剂量，使其取代常规平扫成为可能。Objective To assess the virtual non-contrast liver CT from dual-energy CT for the clinical application. Methods In total, 51 patients were included in the study, and all patients underwent multi-phase liver CT on a dual-source CT. The True non-contrast liver CT （TNCT） was performed in a single-energy acquisition mode, but the arterial and portoveuous liver CT （VNCT） were performed in a dual- energy mode of 110 kV and 140 kV respectively. The virtual non-contrast CT images were derived from the arterial data using liver virtual non-contrast software. Between the true non-contrast CT and the virtual non- contrast CT, the image quality, mean CT HU values in the liver and muscle, signal to noise （SNR） , the radiation dose of volume CT dose index （CTDIvol） and close length product （DLP） in a single phase and total examination were compared with t test. Results There was no significant difference in the detection of liver lesions between TNCT and VNCT. The CT Hu values of muscle on both TNCT and VNCT images were almost equal. The CT HU values of liver on VNCT images were higher than that on TNCT images and the difference was significant [61.32 ±6. 04 vs. （56. 85 ±4. 80） HU, t = -3. 927 ,P 〈0. 01 ]. There was also significant differenc of SNR between TNCT （ 11.28 ± 2. 78 ） and VNCT （ 8.65 ± 1.56） images （ t = - 5. 590, P 〈 0.01 ）. The CTDIvo] and DLP of single phase were （7.07 ± 0.85 ） mGy and （155.11± 22. 52） mGy. cm respectively in TNCT, and （7.05 ± 0. 87） mGy and （ 154.48 ± 23.12） mGy . cm in VNCT. The total CTDIvol and DLP in VNCT were （14. 35± 1.66） mGy and （313.91 ±45. 08）mGy. cm respectively, but in TNCT the total CTDIvol and DLP reached （21.43 ±2. 46） mGy and （469. 02 ± 66. 22） mGy.cm. The difference of CTDIvol and DLP in single phase between TNCT and VNCT showed no significance, but the total CTDIvol and DLP were significantly different（ t = 16. 168 and 13. 132, P 〈 0. 01 ）. Conclusion With the consequent reduction in radi

关 键 词：肝 辐射剂量 体层摄影术 X线计算机 对比研究 

分 类 号：R816.5[医药卫生—放射医学]