前瞻性心电门控100 kV在非肥胖患者冠脉CTA检查中的可行性研究

摘要

目的：评价前瞻性心电门控100kV扫描在非肥胖患者冠状动脉CT血管造影（CTA）检查中的可行性。方法对临床疑诊冠心病而在我院行冠脉CTA检查的118例非肥胖患者随机分为4组，分别采用回顾性心电门控120 kV （组1）、100kV（组2）及前瞻性心电门控120kV（组3）、100kV（组4）四种扫描方案。测量升主动脉根部的CT值及噪声，计算信噪比、对比噪声比，并对图像质量进行主观评分。定量数据表示为平均数±标准差，分类数据表示为比例和百分比。结果118例患者均顺利完成检查，组间体重指数（BMI）差异无统计学意义（ P ＞0．05）。组1、组3的CT值及图像噪声低于组2和组4，差异有统计学意义（ P ＜0．05）；组1的SNR及CNR 高于其余各组，差异均具有统计学意义（ P ＜0.05）；组2、组3、组4的信噪比及对比噪声比组间差异均无统计学意义（ P ＞0.05）。四组间图像主观评分差异无统计学意义（ P ＞0．05）。组4辐射剂量显著降低，平均有效辐射剂量为（1．60±0．16） mSv，组间差异具有统计学意义（ P ＜0.05）。结论对于非肥胖且心律平稳的患者，前瞻性心电门控100 kV扫描方案在降低辐射剂量的同时，可获得满意的图像质量。%Objective To evaluate the feasibility of prospective ECG-triggering acquisition with 100 kV technique in coronary artery angiography of non-obese patients .Methods 118 patients with clinically suspected coronary heart disease were scanned by four different protocols:patients in group 1 and 2, retrospective ECG-gated acquisition with 120 kV and 100 kV were used respec-tively;patients in group 3 and 4, prospective ECG-triggered acquisition with 120 kV and 100 kV were used, respectively.En-hancement and noise of the ascending aorta were quantified .Signal-to-noise ( SNR) , contrast-to-noise ratis ( CNR) was calculat-ed and subjectiveimage quality was evaluated .Quantitative data were expressed as means ± standard deviations and categorical data were given in proportions and percentages .Results The BMI of 118 cases of four groups were not statistically different ( P>0.05).The enhancement and image noise in group 1 and group 3 were lower than group 2 and group 4, and there was statisti-cally difference ( P <0.05); The SNR and CNR were highest in protocol 1, and there was statistically difference in the four groups ( P <0.05).There was no statistically significant difference in SNR and CNR between group 2, 3 and 4 ( P >0.05). There was no statistically significant difference in subjective image quality in the four groups ( P >0.05).Effective dose (ED) in group 4 was (1.60 ±0.16) mSv, and there was significant reduction in group 4 than that in other groups ( P <0.05).Con-clusion In non-obese patients with a stable heart rate , coronary artery angiography performed by prospective ECG-triggered ac-quisition with 100 kV may obtain the diagnostic image with significant reduction of radiation dose .