摘要
目的:在64排螺旋CT(Multidetector Computed Tomography,64-MDCT)冠状动脉CT成像(Computed Tomography Coronary Angiography,CTCA)扫描时采用优化的回顾性心电门控扫描,在保证图像质量的前提下,最大限度地降低辐射剂量。材料与方法:连续选取行64-MDCT CTCA检查的患者100例,将心率控制在65BPM以下,根据扫描方案将患者分为2组,每组均采用回顾性心电门控扫描,根据患者的体重指数(Body Mass Index,BMI)确定管电流及管电压。第1组曝光期相及最大毫安输出均设定为75%R-R间期。第2组曝光期相设定为75%R-R间期,最大毫安输出设定为70%-80%R-R间期。扫描结束后,对两组之间的图像质量、有效剂量(Effective Dose,ED)行统计学分析;P<0.05为差异有统计学意义。结果:两组之间的图像质量无统计学意义,有效剂量有统计学意义。第1组的ED值比第2组降低了20%。结论:优化的回顾性心电门控扫描可以进一步降低辐射剂量。
Purpose： To determine the optimal scan retrospectively ECG-gating of Computed Tomography Coronary Angiography （CTCA） for 64-row multi-detector computed tomography （64-MDCT） and to reduce the radiation dose significantly on the premise of consistent image quality. Materials and Methods： One hundred consecutive patients who are divided into 2 groups are performed CTCA using 64-detector CT. The tube current and voltage is determined by Body Mass Index （BMI）. Retrospective ECG-gated CT angiography is performed with helical scanning direction in the two groups after using ECG automatic tube current modulation technique. The peak tube current and exposure phases are set for 75% cardiac phases of the R-R interval in the first group. The peak tube current is set for 75% cardiac phases of the R-R interval and exposure phases are set for 70%-80% of which in the second group. The image quality and effective Dose （ED） of two groups are compared respectively. P 〈 0. 05 for difference is statistically significant. Results： There are no statistical differences in image quality of two groups, and the ED is the opposite. Compared with the second group, the ED value of the first group is decreased by 20%. Conclusion： An optimal retrospectively ECG-gating can continue to induce radiation dose.
出处
《现代医用影像学》
2014年第6期614-618,共5页
Modern Medical Imageology
