多层螺旋CT“双低”扫描在冠状动脉成像中的临床应用

Clinical Application of Coronary Imaging with “Double Low” Multi-Slice Spiral Computed Tomography Angiography

目的探讨多层螺旋CT低辐射剂量及低对比剂用量在冠状动脉成像中的临床应用。方法对疑诊冠心病并且确定检查的200例患者随机分成A组(n=100,对比剂用量为1.2 m L/kg)、B组(n=100,对比剂用量为0.8 m L/kg),两组患者再随机分为A1,B1,A2和B2 4个亚组。其中A1,B1采用回顾性心电图(Electroca rdiography,ECG)门控技术,A2、B2采用前瞻性ECG触发技术,分别对其进行冠状动脉检查,计算不同组间对比剂用量、图像噪声、图像质量分数及辐射剂量,并进行统计学比较分析。结果本课题成功的完成冠状动脉血管成像(CT Angiography,CTA)检查的病人数194例。1对比剂用量比较,统计结果表明,A组平均用量为82.65 m L,B组平均用量为54.3m L,B组对比剂平均用量比A组减少了约34.3%,B组图像噪声较A组略有提高,总体图像质量评分无统计学意义,可以满足临床诊断的要求;2对照组(A1、B1)和低剂量组(A2、B2组)所得的冠脉图像比较,A2组有效剂量(Effective Dose,ED)值较A1组明显降低,降低幅度约79.7%,B2组ED值较B1组明显降低,降低幅度约78.2%,差异有统计学意义,图像质量评分组间均无统计学差异。结论 1合理减少对比剂用量可以满足冠状动脉CTA的临床诊断要求;2合理选择扫描方案及扫描参数,可以在不降低图像质量的前提下,降低患者的有效辐射剂量。

Objective To investigate the clinical application value of multislicespiral Computed Tomography Angiography (CTA) with low radiation dose and low contrast-medium dose in coronary imaging. Methods To identify 200 patients with suspected coronary heart disease and after examination of patients were randomlLy divided into A group A (n=100, contrast-medium dose was agent for 1.2 mL/kg) and, B group B (n=100, contrast-medium dose was agent for 0.8 mL/kg), further two patients were randomLly divided into four subgroups, which were subgroup A1, A2, B1 and B2 separately., with Subgroup A1 and B1 (control group) underwentused by (A1, B1 with prospectively Electrocardiography (ECG) triggereding technique while subgroup (A2) and. B2, using conventional(low-dose group) byunderwent retrospectively ECG gateding technique) four subgroups of coronary angiography. All patients’ coronary arteries were examined to , computed between different groups of contrastmediumagent doseage, image noise, image quality fraction and radiation dose in the different groups fraction, and which were performed statistical comparative analysis to themlater. Result In this study, 194 of 200 patients (97%) were successfully performed CTA for coronary imaging.① Average dose of contrastmediumfor group A group and group B group was 82.65 mL, and 54.3 mL respectively. The statistical results showed that the average contrastmediumdose of group B reduced 34.3% approximately than that of compared with group A group, image noise of group B group was higher slightly than that of group A group, and the overall image quality fraction was of no statistical significance,which could meet the clinical diagnostic requirements; ② Comparing the coronary artery images of control group (subgroup A1, B1) and low-dose group (subgroup A2, B2), Effective Dose (ED) value of subgroup A2 group declined more apparently than that of subgroup A1 with a reduction of about 79.7%, and ED values of subgroup B2 was also decreased more significantly than that of subgroup B1 with a reduction of about 78.2%, therefore the difference was statistical significantly. However, image quality fraction was of no significant difference. Conclusion ① A reasonable contractmediumdose reduction could meet the clinical diagnosis requirement for CTA on coronary artery; ② A reasonable choice of scanning and scanning parameters could reduce the effective radiation dose without degrading the image quality.