Chinnaiyan Kavitha M, Bilolikar Abhay N, Walsh Edward, Wood Daniel, DePetris Ann, Gentry Ralph, Boura Judith, Abbara Suhny, Al-Mallah Mouaz, Bis Kostaki, Boswell Gilbert, Gallagher Michael, Arunakul Ing-Orn, Halliburton Sandra, Jacobs Jill, Lesser John, Schoepf U Joseph, Valeti Uma S, Raff Gilbert L
Department of Cardiovascular Medicine, William Beaumont Hospital, 3601 W. 13 Mile Road, Royal Oak, MI, USA.
Department of Cardiovascular Medicine, William Beaumont Hospital, 3601 W. 13 Mile Road, Royal Oak, MI, USA.
J Cardiovasc Comput Tomogr. 2014 May-Jun;8(3):205-14. doi: 10.1016/j.jcct.2014.04.001. Epub 2014 Apr 13.
To establish current radiation dose levels with contemporary scanners capable of prospectively triggered or high-pitch spiral scan modes to previous generation scanners among patients evaluated for coronary artery disease, pulmonary embolism, aortic disease, and "triple rule out" in a large population of patients at multiple centers.
Previous small-scale studies with carefully controlled scan protocols report that CT scanners that facilitate prospectively triggered scanning and provide high-pitch spiral CT scan modes drastically lower radiation doses. However, diagnostic reference levels should be selected by medical bodies on the basis of large surveys of representative sites and reviewed at appropriate time intervals.
Scan data including dose and image quality parameters were collected retrospectively from 64 slice scanners (control) and prospectively after sites installed 128-slice dual-source scanners with high-pitch capability (study). Protocol selection was purposely not specified to survey "real world" results. Blinded quantitative image analysis was performed on every fifth scan.
From April 2011 to March 2012, 2085 patients at 9 sites completed the study: 1051 coronary artery disease (509 control, 542 study), 528 pulmonary embolism (267 control, 261 study), 419 aortic disease (268 control, 151 study), and 87 triple rule out (53 control, 34 study). There was a significant reduction in median dose-length product (DLP) from 669 mGy ∙ cm (interquartile range [IQR]: 419-1026 mGy ∙ cm) in the control group to 260 mGy ∙ cm (IQR: 159-441 mGy ∙ cm) in the study group, a reduction by 61% (P < .0001) and was lower in all categories. No significant differences were noted in image quality.
Use of advanced scanners facilitating prospectively triggered or high-pitch spiral scan modes results in marked dose reduction across a variety of cardiovascular studies, with no compromise in image quality. These findings may contribute to new target dose recommendations in societal guidelines.
在多个中心的大量患者中，确定在评估冠状动脉疾病、肺栓塞、主动脉疾病和“三联排除”时，能够进行前瞻性触发或高螺距螺旋扫描模式的当代扫描仪与上一代扫描仪相比的当前辐射剂量水平。
先前采用精心控制的扫描方案的小规模研究报告称，便于进行前瞻性触发扫描并提供高螺距螺旋CT扫描模式的CT扫描仪可大幅降低辐射剂量。然而，诊断参考水平应由医疗机构根据对代表性地点的大规模调查来选择，并在适当的时间间隔进行审查。
回顾性收集64层扫描仪（对照组）的扫描数据，包括剂量和图像质量参数，并在各站点安装具有高螺距功能的128层双源扫描仪后前瞻性收集（研究组）。故意未指定协议选择以调查“实际”结果。对每五次扫描进行盲法定量图像分析。
2011年4月至2012年3月，9个站点的2085名患者完成了研究：1051例冠状动脉疾病（509例对照，542例研究）、528例肺栓塞（267例对照，261例研究）、419例主动脉疾病（268例对照，151例研究）和87例三联排除（53例对照，34例研究）。对照组的中位剂量长度乘积（DLP）从669 mGy∙cm（四分位间距[IQR]：419 - 1026 mGy∙cm）显著降低至研究组的260 mGy∙cm（IQR：159 - 441 mGy∙cm），降低了61%（P <.0001），且在所有类别中均较低。图像质量方面未发现显著差异。
使用便于进行前瞻性触发或高螺距螺旋扫描模式的先进扫描仪，在各种心血管研究中可显著降低剂量，且不影响图像质量。这些发现可能有助于在社会指南中提出新的目标剂量建议。
