Cardiac MR PET CT Program, Department of Radiology and Division of Cardiology, Massachusetts General Hospital and Harvard Medical School, 165 Cambridge St., Suite 400, Boston, MA 02114, USA.
Acad Radiol. 2013 Aug;20(8):1015-23. doi: 10.1016/j.acra.2013.04.012.
Numerous protocols have been developed to reduce cardiac computed tomography angiography (cCTA) radiation dose while maintaining image quality. However, cCTA practice is highly dependent on physician and technologist experience and education. In this study, we sought to evaluate the incremental value of real-time feedback via weekly dose reports on a busy cCTA service.
This time series analysis consisted of 450 consecutive patients whom underwent physician-supervised cCTA for clinically indicated native coronary evaluation between April 2011 and January 2013, with 150 patients before the initiation of weekly dose report (preintervention period: April-September 2011) and 150 patients after the initiation (postintervention period: September 2011-February 2012). To assess whether overall dose reductions were maintained over time, results were compared to a late control group consisting of 150 consecutive cCTA exams, which were performed after the study (September 2012-January 2013). Patient characteristics and effective radiation were recorded and compared.
Total radiation dose was significantly lower in the postintervention period (3.4 mSv [1.7-5.7] and in the late control group (3.3 mSv [2.0-5.3] versus the preintervention period (4.1 mSv [2.1-6.6] (P = .005). The proportion of high-dose outliers was also decreased in the postintervention period and late control period (exams <10 mSv were 88.0% preintervention vs. 97.3% postintervention vs. 95.3% late control; exams <15 mSv were 98.0% preintervention vs. 100.0% postintervention vs. 98.7% late control; exams <20.0 mSv were 98.7% preintervention vs. 100.0% postintervention vs. 100.0% late control).
Weekly dose report feedback of site radiation doses to patients undergoing physician-supervised cCTA resulted in significant overall dose reduction and reduction of high-dose outliers. Overall dose reductions were maintained beyond the initial study period.
已经制定了许多方案来降低心脏 CT 血管造影术（cCTA）的辐射剂量，同时保持图像质量。然而，cCTA 的应用高度依赖于医生和技术人员的经验和教育。在这项研究中，我们试图评估在繁忙的 cCTA 服务中通过每周剂量报告提供实时反馈的增值效果。
这项时间序列分析包括 450 例连续患者，他们在 2011 年 4 月至 2013 年 1 月期间因临床指征行医生监督下的 cCTA 进行原生冠状动脉评估，其中 150 例患者在开始每周剂量报告之前（干预前期间：2011 年 4 月至 9 月），150 例患者在开始之后（干预后期间：2011 年 9 月至 2012 年 2 月）。为了评估总体剂量是否随着时间的推移而保持降低，将结果与研究后进行的 150 例连续 cCTA 检查的晚期对照组进行比较（2012 年 9 月至 2013 年 1 月）。记录并比较患者特征和有效辐射。
干预后期间（3.4 mSv [1.7-5.7]）和晚期对照组（3.3 mSv [2.0-5.3]）的总辐射剂量明显低于干预前期间（4.1 mSv [2.1-6.6]）（P =.005）。干预后期间和晚期对照组中高剂量异常值的比例也有所降低（剂量<10 mSv 的检查比例分别为 88.0%干预前，97.3%干预后，95.3%晚期对照；剂量<15 mSv 的检查比例分别为 98.0%干预前，100.0%干预后，98.7%晚期对照；剂量<20.0 mSv 的检查比例分别为 98.7%干预前，100.0%干预后，100.0%晚期对照）。
向接受医生监督的 cCTA 检查的患者提供网站辐射剂量的每周剂量报告反馈导致总体剂量显著降低，并且降低了高剂量异常值。总体剂量降低在初始研究期间后仍保持。
