绝对时相窄窗自适应前门控降低心律不齐冠状动脉CT成像辐射剂量的研究  

The study on reducing radiation dose in coronary CT angiography for patients with arrhythmia using absolute phase and narrow window in prospective electrocardiogram-gating

作　　者：曹希明[1] 郑君惠[1] 李景雷[1] 巫梓斌[1] 王振邦[1] Cao Ximing;Zheng Junhui;Li Jinglei;Wu Zibin;Wang Zhenbang(Department of Radiology,Guangdong Provincial People′s Hospital,Guangdong Academy of Medical Sciences,Guangzhou 510080,China)

机构地区：[1]广东省人民医院放射科广东省医学科学院,广州510080

出　　处：《中华放射医学与防护杂志》2022年第9期716-721,共6页Chinese Journal of Radiological Medicine and Protection

摘　　要：目的探讨绝对时相窄窗曝光降低心律不齐者自适应前瞻性心电门控冠状动脉CT成像辐射剂量的可行性。方法纳入心律不齐冠状动脉CT成像检查者200例,根据随机数表法分为A、B两组,每组100例,两组均行自适应前瞻性心电门控序列冠状动脉CT扫描。A组采用绝对时相窄窗曝光(250~450 ms),B组采用相对时相宽窗曝光(30%~75%),其他扫描参数相同,两组对比剂注射方案相同,扫描完成后对图像质量进行评价并记录辐射剂量,比较两组间图像质量和辐射剂量。结果两组的图像质量评分差异无统计学意义(P>0.05)。A组容积CT剂量指数(CTDIvol)、剂量长度乘积(DLP)、有效剂量(E)分别为(16.71±8.35)mGy、(231.04±114.86)mGy·cm、(3.23±1.60)mSv,均明显低于B组的(29.35±17.90)mGy、(398.27±238.40)mGy·cm、(5.57±3.33)mSv,差异有统计学意义(t=-6.40、-6.32、-6.32,P<0.05)。A组中未出现重复扫描、出现1次、2次、3次重复扫描的例数分别为81、17、2和0,而B组分别为22、62、10和6例,差异有统计学意义(χ^(2)=70.76,P<0.05)。结论对于心律不齐者,自适应前瞻性心电门控扫描模式,同时采用绝对时相ms扫描及重建,并且缩窄曝光时间窗,能在保证图像质量的同时降低辐射剂量。Objective To investigate the feasibility of reducing radiation dose in coronary CT angiography for patients with arrhythmia with absolute phase and narrow window in prospective electrocardiogram-gating.Methods 200 patients with arrhythmia underwent coronary CT angiography procedure with prospective electrocardiogram-gating adaptive sequence in dual source CT were randomly divided into 2 groups according to the scan mode.Group A was scanned with absolute phase and narrow window(250-450 ms)and group B uesd relative phase and wide window(30%-75%).The other parameters and injection protocol of contrast media were the same in 2 groups.Both image quality and radiation dose of the 2 groups were analyzed.Results No significant difference of image quality was found between the 2 groups.CTDIvol,DLP,E of group A were all lower than those in group B[CTDIvol:(16.71±8.35)vs.(29.35±17.90)mGy,DLP:(231.04±114.86)vs.(398.27±238.40)mGy·cm,E:(3.23±1.60)vs.(5.57±3.33)mSv,t=-6.40,-6.32、-6.32,P<0.05].The patients with repeat scan cycles in group A and group B were 81 vs.22 for 0 cycle,17 vs.62 for 1 cycle,2 vs.10 for 2 cycles,0 vs.6 for 3 cycles(χ^(2)=70.76,P<0.05).Conclusions The prospective electrocardiogram-gating adaptive CCTA sequence with absolute phase and narrow window can reduce radiation dose while the image quality meets the requirementsfor patients with arrhythmia.

关 键 词：冠状动脉 心律不齐 辐射剂量 图像质量 绝对时相 

分 类 号：R541.7[医药卫生—心血管疾病] R816.2[医药卫生—内科学]