前瞻性心电门控100kV在非肥胖患者冠脉CTA检查中的可行性研究

Feasibility of coronary artery angiography using prospective ECG-triggering acquisition with 100 kV in non-obese patients

目的评价前瞻性心电门控100k V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120k V(组1)、100k V(组2)及前瞻性心电门控120k V(组3)、100k V(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)m Sv,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100k V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 .