双层探测器光谱CT虚拟单能级成像显示甲状腺上动脉的价值  

The value of virtual monoenergetic images based on dual-layer spectral detector CT for demonstrating superior thyroid artery

作　　者：彭丽娅 瞿姣 尹娇 刘思佳 杨亚英[1] PENG Liya;QU Jiao;YIN Jiao;LIU Sijia;YANG Yaying(Department of Medical Imaging,the First Affiliated Hospital of Kunming Medical University,Kunming 650032,China;Department of Radiology,West China Hospital of Sichuan University,Chengdu 610041,China)

机构地区：[1]昆明医科大学第一附属医院医学影像科,云南昆明650032 [2]四川大学华西医院放射科,四川成都610041

出　　处：《实用放射学杂志》2023年第12期2054-2057,共4页Journal of Practical Radiology

摘　　要：目的探讨双层探测器光谱CT显示甲状腺上动脉(STA)的最佳虚拟单能级图像,优化STA的图像质量。方法回顾性选取100例行颈部光谱CT双期增强扫描的患者,分析动脉期120 kVp常规图像及基于能谱的40~70 keV(间隔10 keV)虚拟单能级图像。在5组图像上分析血管及周围组织的CT值、背景噪声、信噪比(SNR)、对比噪声比(CNR),并对图像质量进行评分。结果在单能级图像组中,随着能级水平的降低,STA的CT值、SNR、CNR均升高,当能级为40 keV时最高,显著高于120 kVp常规图像组(P<0.05)。背景噪声随着能级水平的降低而增高,在40 keV时最大,但仍低于120 kVp常规图像组,与120 kVp常规图像组比较差异有统计学意义(P<0.001)。40 keV单能级图像上的主观评分明显优于120 kVp常规图像组(P<0.001)。在对100例STA起源的评估中,共显示200支STA,其中69%起源于颈外动脉。结论40 keV单能级图像上STA的图像质量显著高于常规图像,在评估STA的解剖时具有明显的优势。Objective To explore the optimal virtual monoenergetic image of superior thyroid artery(STA)based on dual-layer spectral detector CT,and to optimize the image quality of STA.Methods A total of 100 patients who underwent dual-phase neck enhanced spectral CT scan were selected retrospectively.The 120 kVp conventional images and the 40-70 keV(interval of 10 keV)virtual monoenergetic images in the arterial phase were analyzed.The CT values,background noise,signal-to-noise ratio(SNR)and contrast-to-noise ratio(CNR)of blood vessels and surrounding tissues were analyzed in the five groups of images,and the image quality was scored.Results In monoenergetic image groups,the CT values,SNR and CNR of STA increased with the monoenergetic level decreased,and the highest values were found when the monoenergetic level was 40 keV,which was significantly higher than those in the 120 kVp conventional image group(P<0.05).The background noise increased with the monoenergetic level decreased,and reached the maximum at 40 keV,but it was still lower than that in the 120 kVp conventional image group,and the difference was statistically significant(P<0.001).The subjective score of 40 keV image was significantly better than that of 120 kVp conventional image group(P<0.001).In the evaluation of the origin of the STA in 100 patients,a total of 200 STA were shown,69%of which originated from the external carotid artery.Conclusion The image quality of the STA on the 40 keV monoenergetic image is significantly higher than that on the conventional image,which has obvious advantages in evaluating the anatomy of the STA.

关 键 词：计算机体层成像 甲状腺上动脉 虚拟单能级图像 图像质量 

分 类 号：R814.42[医药卫生—影像医学与核医学] R816.1[医药卫生—放射医学]