Colocalization of thin-walled dome regions with low hemodynamic wall shear stress in unruptured cerebral aneurysms Clinical article
Colocalization of thin-walled dome regions with low hemodynamic wall shear stress in unruptured cerebral aneurysms Clinical article
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DOI：
10.3171/2013.2.jns12968
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发表时间：
2013-07-01
影响因子：
4.1
通讯作者：
Malek, Adel M.
中科院分区：
文献类型：
--
作者：
Kadasi, Laith M.;Dent, Walter C.;Malek, Adel M.
Object.壁切应力（WSS）在调节内皮功能中起作用，并被怀疑在脑动脉瘤破裂中起作用。本研究的目的是评估动脉瘤圆顶局部变薄与估计的血流动力学因素之间的空间关系，假设低WSS与动脉瘤壁退化相关。基于旋转血管造影容积对14例患者的16个动脉瘤进行稳态计算流体动力学分析，以导出WSS、其空间梯度（WSSG）和压力的标测图。根据高分辨率术中显微镜检查结果的组织透明度，分类估计局部圆顶厚度。对每个计算模型进行定向，以匹配相应的术中视图，并在薄的和正常的相邻圆顶区域进行数字采样，在颈部和载瘤血管进行对照。压差计算为动脉瘤圆顶点与平均瘤颈压力之间的差值。对7例患者进行了搏动时间依赖性验证性分析。配对分析显示，薄壁圆顶区域的WSS水平（0.381 Pa vs 0.816 Pa; p < 0.0001）显著低于相邻基线厚度区域。同样，log WSSG和log WSS x WSSG在薄区域均较低（均p < 0.0001）;多变量逻辑回归分析将较低的WSS和较高的压差确定为较低壁厚的独立相关因素，曲线下面积为0.80。在稳态和时间依赖性脉动分析中均观察到这种关系。未破裂脑动脉瘤的薄壁区域与低WSS共存，表明血流停滞区域与动脉瘤壁变薄之间存在细胞机械传导联系。
Object. Wall shear stress (WSS) plays a role in regulating endothelial function and has been suspected in cerebral aneurysm rupture. The aim of this study was to evaluate the spatial relationship between localized thinning of the aneurysm dome and estimated hemodynamic factors, hypothesizing that a low WSS would correlate with aneurysm wall degeneration.Methods. Steady-state computational fluid dynamics analysis was performed on 16 aneurysms in 14 patients based on rotational angiographic volumes to derive maps of WSS, its spatial gradient (WSSG), and pressure. Local dome thickness was estimated categorically based on tissue translucency from high-resolution intraoperative microscopy findings. Each computational model was oriented to match the corresponding intraoperative view and numerically sampled in thin and normal adjacent dome regions, with controls at the neck and parent vessel. The pressure differential was computed as the difference between aneurysm dome points and the mean neck pressure. Pulsatile time-dependent confirmatory analysis was carried out in 7 patients.Results. Matched-pair analysis revealed significantly lower levels of WSS (0.381 Pa vs 0.816 Pa; p < 0.0001) in thin-walled dome areas than in adjacent baseline thickness regions. Similarly, log WSSG and log WSS x WSSG were both lower in thin regions (both p < 0.0001); multivariate logistic regression analysis identified lower WSS and higher pressure differential as independent correlates of lower wall thickness with an area under the curve of 0.80. This relationship was observed in both steady-state and time-dependent pulsatile analyses.Conclusions. Thin-walled regions of unruptured cerebral aneurysms colocalize with low WSS, suggesting a cellular mechanotransduction link between areas of flow stasis and aneurysm wall thinning.