能谱CT显示胰腺血管网:与混合能量CT对照  

Spectral CT in demonstration of pancreatic vascular network:Comparison with conventional CT

作　　者：史燕杰[1,2] 孙应实[1,2] 齐丽萍[1,2] 李英[1,2] 曹崑[1,2] 刘玉良[1,2] 李晓婷[1,2] 张晓鹏[1,2] 

机构地区：[1]北京大学肿瘤医院 [2]北京市肿瘤防治研究所医学影像科恶性肿瘤发病机制及转化研究教育部重点实验室,北京100142

出　　处：《中国医学影像技术》2014年第2期245-249,共5页Chinese Journal of Medical Imaging Technology

基　　金：国家重点基础研究发展计划(973计划)项目(2011CB707705);国家自然科学基金(81371715);北京市科学技术委员会:首都特色临床应用研究(Z121107001012115)

摘　　要：目的探讨能谱CT单能图像改善胰腺血管网显示的能力。方法将47例非胰腺病变患者随机分为能谱CT组（27例）和VCT扫描组（20例）。由1名观察者测量11组能谱CT单能图像（40-140keV，间隔10keV）及1组VCT混合能量图像的噪声、CNR、信号强度比（SIR）、SNR值，并行VR、MIP重建；2名观察者独立盲法观察，以5分法评价显示胰腺血管网的能力。结果能谱CT50-70keV图像胰腺血管网评分明显高于40keV、80-140keV（P均〈O．05）；2名观察者对各组单能图像评分的一致性为一般或良（O．403-0．843）。70keV组图像噪声明显低于40-60keV组（P〈O．05）。能谱CT70keV图像胰腺血管网评分明显优于120kVp图像（P〈O．05）；在噪声、扫描剂量无显著差异的情况下，与120kVp图像比较，CT70keV胃十二指肠动脉CT值、CNR、SIR、SNR分别提高了29．06％、58．07％、22．22％、31．28％。结论与混合能量CT相比，能谱CT单能图像能更好地显示胰腺血管网。Objective To investigate the performance of spectral CT in visualization of pancreatic vascular network com- pared with conventional polychromatic CT. Methods Forty-seven patients without pancreatic lesions were randomly divid- ed into spectral CT group （n=27） and VCT group （n=20）. A total of 11 groups of monochromatic images ranging from 40 keV to 140 keV at an interval of 10 keV were generated. CNR, signal intensity ratio （SIR）, signal to noise ratio （SNR） and image noise were compared. A 5-score classification system was used to evaluate the performance of CT images in visu- alization of pancreatic vascular network by two observers blindly. Results The best energy level for displaying the vascular network by spectral CT was 50-70 keV. The inter-observer agreement for the image scores between two observers was at moderate to good level （Kappa value 0. 403-0. 843）. Noise of 70 keV images reduced compared with that of 40--60 keV images （P〈0.05）. Compared with polychromatic images, CT value, CNR, SIR and SNR of gastroduodenal artery on 70 keVimages increased by 29.06%, 58.07%, 22.22% and 31.28%, respectively. The vascular network visualization and distinct display rate of 70 keV were both higher than those of polychromatic images （P〈0.05）. Conclusion Compared with Dolvchromatic CT, spectral CT can improve visualization of pancreatic vascular network.

关 键 词：胰腺 血管网 体层摄影术 X线计算机 

分 类 号：R322.491[医药卫生—人体解剖和组织胚胎学] R814.42[医药卫生—基础医学]