光谱CT显示左结肠动脉的最佳虚拟单能量  

The optimal virtual single energy of spectral CT for displaying the left colonic artery

作　　者：陈海静 李青青[1] 赵卫[1] 胡继红[1] 吴岩[1] 杨亚英[1] CHEN Hai-jing;LI Qing-qing;ZHAO Wei(Department of Radiology,the First Affiliated Hospital of Kunming Medical University,Kunming 650032,China)

机构地区：[1]昆明医科大学第一附属医院医学影像科,昆明650032

出　　处：《放射学实践》2024年第3期388-392,共5页Radiologic Practice

基　　金：云南省放射与治疗临床医学研究中心专项基金子课题项目(202102AA100067);云南省科技厅科技计划项目(202101AY070001-103)。

摘　　要：目的:探讨双层探测器光谱CT显示左结肠动脉(LCA)的最佳虚拟单能量,旨在为腹腔镜直肠癌根治术前评估LCA提供帮助。方法:回顾性分析在本院行腹部CT血管成像(CTA)扫描的100例患者的影像学资料,将动脉期原始图像重组成混合能量图像以及基于能谱的间隔10 keV的40~70 keV的单能量图像。对5组图像LCA的CT值、信噪比(SNR)、对比噪声比(CNR)、图像噪声以及图像质量评分进行比较。结果:40~70 keV组单能量图像LCA的CT值、噪声、CNR、SNR随着能级的升高呈递减趋势。常规混合能量图像组及40~70 keV单能量图像组两两比较,各组间CT值、SNR、CNR、噪声差异有统计学意义(P<0.05)。40 keV组图像LCA的CT值、CNR、SNR均高于其他组,噪声低于常规混合能量图像组。两名影像科医师图像质量主观评价的一致性良好(0.40≤Kappa值<0.75),各组间图像主观评分差异均有统计学意义(P均<0.001)。40 keV组图像主观评分最高,40~70 keV组单能量图像质量均高于常规混合能量图像。结论:40 keV为显示LCA的最佳虚拟单能量,显示血管清晰、边缘锐利,能更清晰显示LCA及其解剖变异,利于外科医生腹腔镜直肠癌根治术的顺利进行。Objective:The purpose of this study was to investigate the optimal virtual single energy of double-layer detector spectral CT for displaying the left colonic artery(LCA),so as to provide assistance for the evaluation of LCA before laparoscopic radical rectal resection.Methods:The images of 100 patients who underwent abdominal CT angiography in our hospital were retrospectively analyzed.The original images of the arterial phase were reconstructed into mixed energy images and four groups of single energy images based on energy spectrum of 40~70keV with an interval of 10keV.The CT value,signal-to-noise ratio(SNR),contrast-to-noise ratio(CNR),image noise and image quality scores of the LCA of the five groups of images were compared.Results:The CT value,noise,CNR and SNR of the LCA of single-energy images in the 40~70keV group decreased with the increase of energy level.Compared with the conventional mixed energy image group and the 40~70keV single-energy image group,the differences in CT value,SNR,CNR and noise between the groups were statistically significant(P<0.05).The CT value,CNR,and SNR of the LCA of the 40keV group were higher than those of other groups,and the noise was lower than that of the conventional mixed energy image group.The subjective evaluation of image quality of the two radiologists was consistent well(0.40≤Kappa value<0.75),and the subjective score of image was statistically significant between the groups(P<0.001).The subjective score of images in the 40keV group was the highest,and the single-energy image quality in the 40~70keV group was higher than that of conventional mixed energy images.Conclusion:40keV is the best virtual single energy display of LCA,showing clear blood vessels with sharp edges,which can more clearly display LCA and its anatomical variants,which is conducive to the smooth progress of laparoscopic radical rectal cancer resection by surgeons.

关 键 词：双层探测器光谱CT 左结肠动脉 虚拟单能量图像 图像质量 

分 类 号：R814.42[医药卫生—影像医学与核医学] R735.37[医药卫生—放射医学]