宝石能谱CT双低检查技术在颅脑CTA中的应用研究  

Application research of gemstone spectral CT double-low examination technology in cranial CTA

作　　者：徐军 张又新 吴红英[1] 胡孝梨 雷子乔[1] 罗昆[1] XU Jun;ZHANG You-xin;WU Hong-ying(Department of Radiology,Union Hospital,Tongii Medical College,Huazhong University of Science and Technology,Hubei Province Key Laboratory of Molecular Imaging,Wuhan 430022,China)

机构地区：[1]华中科技大学同济医学院附属协和医院放射科,分子影像湖北省重点实验室,武汉430022

出　　处：《放射学实践》2022年第3期297-301,共5页Radiologic Practice

摘　　要：目的:探讨宝石能谱CT最佳单能量成像结合自动能谱协议选择技术在颅脑CTA检查中的应用价值。方法:将120例行颅脑CTA的患者随机分为两组,常规剂量组和能谱低剂量组,扫描前两组均采用15 mL的对比剂和20 mL的生理盐水进行小剂量团注测试,估算出对比剂到达靶血管的峰值时间。扫描时常规剂量组60例行常规扫描,管电压为120 kVp,0.7 mL/kg对比剂,流率4.0 mL/s,能谱低剂量组60例采用能谱双能量扫描模式及自动能谱协议选择技术,管电压为140、80 kV瞬时切换,0.5 mL/kg对比剂,流率3.0 mL/s,扫描后重建出最佳单能量65 keV的图像。比较常规剂量组和能谱低剂量组右颈内动脉、右大脑中动脉、右侧颞肌和窦汇CT值、图像背景噪声(SD)、信噪比(SNR)、对比噪声比(CNR)、CT剂量指数(CTDIvol)、剂量长度乘积(DLP)、有效辐射剂量(ED)以及图像质量主观评分的差异。结果:两组图像右颈内动脉、右大脑中动脉和右侧颞肌的强化CT值差异没有统计学意义(t=-0.465、0.560、-1.525,P>0.05),窦汇的CT值差异有统计学意义(Z=-6.456,P<0.05)。两组图像的SD、SNR、CNR和主观评分差异没有统计学意义(t=-0.975,Z=-0.530、-0.409,χ2=0.635,P>0.05)。两组患者的辐射剂量(CTDL、DLP、ED)和对比剂剂量差异有统计学意义(t'=15.904、15.849、15.849,t=12.235,P<0.05)。结论:运用宝石能谱CT最佳单能量成像结合自动能谱协议选择技术在颅脑CTA检查中可以降低患者的对比剂剂量和辐射剂量,且与常规扫描模式相比,可有同等的动脉显示效果以及信噪比。Objective:To explore the application value of gemstone spectral CT optimal single-energy imaging combined with automatic spectral imaging protocol selection technology in cranial CTA examination.Methods:One hundred and twenty patients undergoing cranial CTA were randomly divided into the conventional-dose group and the spectral low-dose group.Before scanning, 15 mL contrast agent and 20 mL normal saline were used for the low-dose bolus test in both groups to estimate the peak time for the contrast agent to reach the target vessel.The conventional group(60 cases) was scanned with 120 kVp tube voltage, and 0.7 mL/kg contrast agent with a flow rate of 4.0 mL/s.The spectral low-dose group(60 cases) was scanned in dual-energy scanning mode using automatic spectral imaging protocol selection technology with instantaneous switching tube voltage between 140 and 80 kV,0.5 mL/kg contrast agent with a flow rate of 3.0 mL/s.After scanning, the optimal single energy 65 keV image was reconstructed.The CT value, image background noise(SD),signal-to-noise ratio(SNR),contrast-to-noise ratio(CNR),CT dose index(CTDIvol),dose length product(DLP),effective radiation dose(ED),and subjective scores of image quality in the right internal carotid artery, right middle cerebral artery, right temporalis muscle, and sinus confluence were compared between the conventional-lose group and spectral low-dose group.Results:There were no significant differences in the enhanced CT value of the right internal carotid artery, right middle cerebral artery, and right temporalis muscle between the two groups(t=-0.465,0.560,-1.525,P>0.05).However, the difference of CT values in sinus confluence was statistically significant(Z=-6.456,P<0.05).There was no significant difference in SD,SNR,CNR,and subjective scores between the two groups(t=-0.975,Z=-0.530,-0.409,χ;=0.635,P>0.05).However, there were statistical differences in the radiation dose(CTDL,DLP,and ED) and contrast agent dose between the two groups(t’=15.904,15.849,15.849,t=12.235,P<0.05).Conclusio

关 键 词：宝石能谱CT 最佳单能量 颅脑CTA 对比剂 

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]