PolitoBIOMed Lab, Department of Mechanical and Aerospace Engineering, Politecnico di Torino, Corso Duca degli Abruzzi, 24-10129 Turin, Italy.
Bao Research Group, Department of Chemical Engineering, Stanford University, Stanford, CA, USA.
Med Eng Phys. 2017 Sep;47:64-71. doi: 10.1016/j.medengphy.2017.03.011. Epub 2017 Jun 21.
In this study, an image-based morphometry toolset quantifying geometric descriptors of the left ventricle, aorta and their coupling is applied to investigate whether morphological information can differentiate between subjects affected by diastolic dysfunction (patient group) and their age-matched controls (control group). The ventriculo-aortic region of 20 total participants (10 per group) were segmented from high-resolution 3D magnetic resonance images, from the left ventricle to the descending aorta. Each geometry was divided into segments in correspondence of anatomical landmarks. The orientation of each segment was estimated by least-squares fitting of the respective centerline segment to a plane. Curvature and torsion of vessels' centerlines were automatically extracted, and aortic arch was characterized in terms of height and width. Tilt angle between subsequent best-fit planes in the left ventricle and ascending aorta regions, curvature and cross-sectional area in the descending aorta resulted significantly different between patient and control groups (P-values< 0.05). Aortic volume (P = 0.04) and aortic arch width (P = 0.03) resulted significantly different between the two groups. The observed morphometric differences underlie differences in hemodynamics, by virtue of the influence of geometry on blood flow patterns. The present exploratory analysis does not determine if aortic geometric changes precede diastolic dysfunction, or vice versa. However, this study (1) underlines differences between healthy and diastolic dysfunction subjects, and (2) provides geometric parameters that might help to determine early aortic geometric alterations and potentially prevent evolution toward advanced diastolic dysfunction.
在这项研究中，应用了一种基于图像的形态计量工具集，用于量化左心室、主动脉及其耦合的几何描述符，以研究形态学信息是否可以区分舒张功能障碍患者（患者组）和年龄匹配的对照组（对照组）。从高分辨率 3D 磁共振图像中分割出 20 名总参与者（每组 10 名）的心室 - 主动脉区域，从左心室到降主动脉。每个几何形状都按照解剖学标志分为几段。通过将各中心线段最小二乘拟合到平面来估计每个段的方向。自动提取血管中心线的曲率和扭转，并根据高度和宽度描述主动脉弓的特征。左心室和升主动脉区域后续最佳拟合平面之间的倾斜角、降主动脉的曲率和横截面积在患者组和对照组之间有显著差异（P 值 < 0.05）。两组之间主动脉体积（P = 0.04）和主动脉弓宽度（P = 0.03）有显著差异。血流动力学的差异是由几何形状对血流模式的影响引起的，这种形态差异的存在。本探索性分析并未确定主动脉几何变化是否先于舒张功能障碍，或者反之亦然。然而，这项研究（1）强调了健康和舒张功能障碍患者之间的差异，（2）提供了可能有助于确定早期主动脉几何改变并潜在预防向晚期舒张功能障碍发展的几何参数。
