Department of Radiology and Cardiovascular Imaging Center, Cardiac and Vascular Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-dong, Gangnam-gu, Seoul 135-710, Korea.
Int J Cardiovasc Imaging. 2013 Apr;29(4):875-84. doi: 10.1007/s10554-012-0138-x. Epub 2012 Oct 18.
The aim of this study was to compare the radiation dose and image quality of different adenosine-stress dynamic myocardial perfusion CT protocols using a 128-slice dual-source computed tomography (DSCT) scanner. We included 330 consecutive patients with suspected coronary artery disease. Protocols employed the following dynamic scan parameters: protocol I, a 30-s scan with a fixed tube current (FTC, n = 172); protocol II, a 30-s scan using an automatic tube current modulation (ATCM) technique (n = 108); protocol III, a 14-s scan using an ATCM (n = 50). To determine the scan interval for protocol III, we analyzed time-attenuation curves of 26 patients with myocardial perfusion who had been scanned using protocol I or II. The maximum attenuation difference between normal and abnormal myocardium occurred at 18.0 s to 30.3 s after initiation of contrast injection. Myocardial perfusion images of FTC and ATCM were of diagnostic image quality based on visual analysis. The mean radiation dose associated with protocols I, II, and III was 12.1 ± 1.6 mSv, 7.7 ± 2.5 mSv, and 3.8 ± 1.3 mSv, respectively (p < 0.01). Use of a dose-modulation technique and a 14-s scan duration for adenosine-stress CT enables significant dose reduction while maintaining diagnostic image quality.
本研究旨在比较使用 128 层双源 CT（DSCT）扫描仪的不同腺苷负荷动态心肌灌注 CT 方案的辐射剂量和图像质量。我们纳入了 330 例疑似冠心病患者。方案采用以下动态扫描参数：方案 I，30 秒固定管电流（FTC）扫描（n = 172）；方案 II，30 秒自动管电流调制（ATCM）技术扫描（n = 108）；方案 III，14 秒 ATCM 扫描（n = 50）。为了确定方案 III 的扫描间隔，我们分析了 26 例使用方案 I 或 II 进行心肌灌注扫描的患者的时间衰减曲线。在开始注射造影剂后 18.0 秒至 30.3 秒，正常和异常心肌之间的最大衰减差异最大。根据视觉分析，FTC 和 ATCM 的心肌灌注图像具有诊断图像质量。方案 I、II 和 III 的平均辐射剂量分别为 12.1 ± 1.6 mSv、7.7 ± 2.5 mSv 和 3.8 ± 1.3 mSv（p < 0.01）。使用剂量调制技术和 14 秒的腺苷负荷 CT 扫描时间可以显著降低剂量，同时保持诊断图像质量。
