Keller Eric J, Fang Shanna, Lin Kai, Freed Benjamin H, Smith Peter M, Spottiswoode Bruce S, Davids Rachel, Carr Maria, Jolly Marie-Pierre, Markl Michael, Carr James C, Collins Jeremy D
Department of Radiology, Feinberg School of Medicine, Northwestern University, 737 N. Michigan Ave Suite 1600, Chicago, IL, USA.
Department of Cardiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.
Int J Cardiovasc Imaging. 2017 Aug;33(8):1169-1177. doi: 10.1007/s10554-017-1090-6. Epub 2017 Feb 26.
The purpose of this study was to assess the consistency of semi-automated myocardial strain analysis by prototype software across field strengths, temporal resolutions, and examinations. 35 volunteers (48 ± 13 years; 20% women) and 25 patients (54 ± 12 years; 44% women) without significant cardiac dysfunction underwent cine cardiac magnetic resonance imaging (CMR) at 1.5 T with a temporal resolution of 39.2 msec. 34 subjects also underwent imaging at 3.0 T; 16 had repeat examinations within 14 days; and 9 underwent CMR with temporal resolutions of 12.5 and 39.2 msec on the same day. Prototype heart deformation analysis (HDA) software was used to retrospectively quantify strain from segmented balanced steady state free precession (bSSFP) cinegraphic images. Myocardial contours were automatically generated on short axis images and drawn at end-diastole by two independent reviewers on long-axis images. Contours were automatically propagated throughout the cardiac cycle. Global and regional peak systolic strain were compared across observers, field strengths, temporal resolutions, and examinations. Inter-observer agreement was excellent (ICC > 0.87, p < 0.01). Inter-examination variability was low, ranging from 1.7 (1.0-2.4)% to 2.5 (1.9-3.1)%, except for radial strain: 9.2 (7.6-10.5)%. Most global and regional strain values were not significantly different across field strengths and temporal resolutions (p > 0.05). Normal global peak systolic strain values with HDA were -25.0 (-24.0 to -26.1)% (LV circumferential), 60.5 (55.3 to 65.6)% (LV radial), -22.3 (-20.5 to - 24.0)% (LV longitudinal), and -26.0 (-23.8 to -28.2)% (RV longitudinal). HDA prototype software enabled efficient and consistent quantification of myocardial strain from conventional bSSFP cine CMR data, demonstrating clinical feasibility.
本研究的目的是评估原型软件在不同场强、时间分辨率和检查条件下进行半自动心肌应变分析的一致性。35名志愿者（48±13岁；20%为女性）和25名无明显心脏功能障碍的患者（54±12岁；44%为女性）接受了1.5T的心脏磁共振成像（CMR）电影检查，时间分辨率为39.2毫秒。34名受试者还接受了3.0T的成像检查；16名在14天内进行了重复检查；9名在同一天接受了时间分辨率为12.5毫秒和39.2毫秒的CMR检查。使用原型心脏变形分析（HDA）软件对分割的平衡稳态自由进动（bSSFP）电影图像进行回顾性应变量化。心肌轮廓在短轴图像上自动生成，并由两名独立的审阅者在长轴图像的舒张末期绘制。轮廓在整个心动周期中自动传播。比较了观察者、场强、时间分辨率和检查之间的整体和区域峰值收缩期应变。观察者间的一致性极佳（ICC>0.87，p<0.01）。除径向应变为9.2（7.6-10.5）%外，检查间的变异性较低，范围为1.7（1.0-2.4）%至2.5（1.9-3.1）%。大多数整体和区域应变值在场强和时间分辨率之间无显著差异（p>0.05）。使用HDA时正常的整体峰值收缩期应变值为-25.0（-24.0至-26.1）%（左心室圆周）、60.5（55.3至65.6）%（左心室径向）、-22.3（-20.5至-24.0）%（左心室纵向）和-26.0（-23.8至-28.2）%（右心室纵向）。HDA原型软件能够从传统的bSSFP电影CMR数据中高效且一致地量化心肌应变，证明了其临床可行性。
