摘要
目的:探讨在低体重指数患者中使用80 kVp管电压的前瞻性心脏冠脉CTA成像的可行性。方法:对84例临床上怀疑冠心病的患者应用80 kVp管电压的前瞻性心脏冠脉CTA检查。按BMI分为80 kVp(BMI≤22 kg/m^2)和100 kVp(22<BMI≤25)2组。脉冲曝光时间为200 ms(心率≦65次/分)或380 ms(心率>65次/分)。分析直径≥1.5 mm的冠脉节段的图像质量(1~4分),比较各组的图像质量及辐射剂量。结果:两组患者的年龄、身高、心率的一致性较好(P>0.05)。80 k Vp、100 k Vp组的ED分别为(0.56±0.21)mSv、(1.43±0.58)mSv。两组的CT容积剂量指数(CT dose index volume,CTDIvol)、剂量长度乘积(dose length product,DLP)、ED存在显著的统计学差异((P=0.000)。80 kVp、100 kVp组的合格图像分别为92.2%、91.8%。两组的图像质量评分、主动脉SNR及左、右冠主干CNR无统计学差异(P>0.05)。结论:80 kVp的超低剂量前瞻性冠脉CTA可以应用于低体重指数患者,图像质量足以满足诊断需要,辐射剂量显著降低。
Objective: To investigate the feasibility of prospective coronary computed tomography angiography (CTA) using tube voltage of 80 kVp in patients with low body mass index (BMI). Methods: Eighty-four patients with suspected coronary artery disease (CAD) underwent prospective ECG-gate coronary CTA. The cases were divided into two groups based on BMI: One group (BMI 〈 22 kg/mz) was examined with 80 kVp, and the other group (22 〈 BMI 〈 25) with 100 kVp. If heart rates 〈 65beats/min, pulse exposure time was set at 200 ms, otherwise 380ms. The imaging qualities of coronary artery segments with diameter 〉 1.5 mm were evaluated. Image quality and radiation dose were compared between groups. Results: The age, height, and heart rate were insignificantly different between groups. In the 80 kVp and 100 kV groups, the EDs were 0.56 ±0.21 and (1.43 ± 0.58) mSv, respectively. There were significant differences in CT dose index volume (CTDIvol), dose length product (DLP) and ED between groups. The image quality rates (score of 3 or 4) were 92.2% and 91.8% in the 80 kVp and 100 kVp groups, respectively. In image quality scores, aortic SNR and coronary trunk CNR had no significant differences between two groups. Conclusion: Prospective coronary CTA using tube voltage of 80 kVp in low-BMI patients can provide adequate coronary diagnostic information; while significantly reduce the radiation dose,
出处
《CT理论与应用研究(中英文)》
2017年第1期99-106,共8页
Computerized Tomography Theory and Applications