1Department of Neurosurgery, Tohoku University Graduate School of Medicine; and.
Departments of2Neuroanaethesia.
J Neurosurg. 2018 Mar;128(3):723-730. doi: 10.3171/2016.10.JNS161695. Epub 2017 Mar 3.
OBJECTIVE Risk factors for aneurysm rupture have been extensively studied, with several factors showing significant correlations with rupture status. Several studies have shown that aneurysm shape and hemodynamics change after rupture. In the present study the authors investigated a static factor, the bifurcation angle, which does not change after rupture, to understand its effect on aneurysm rupture risk and hemodynamics. METHODS A hospital database was retrospectively reviewed to identify patients with cerebral aneurysms treated surgically or endovascularly in the period between 2008 and 2015. After acquiring 3D rotational angiographic data, 3D stereolithography models were created and computational fluid dynamic analysis was performed using commercially available software. Patient data (age and sex), morphometric factors (aneurysm volume and maximum height, aspect ratio, bifurcation angle, bottleneck ratio, and neck/parent artery ratio), and hemodynamic factors (inflow coefficient and wall shear stress) were statistically compared between ruptured and unruptured groups. RESULTS Seventy-one basilar tip aneurysms were included in this study, 22 ruptured and 49 unruptured. Univariate analysis showed aspect ratio, bifurcation angle, bottleneck ratio, and inflow coefficient were significantly correlated with a ruptured status. Logistic regression analysis showed that aspect ratio and bifurcation angle were significant predictors of a ruptured status. Bifurcation angle was inversely correlated with inflow coefficient (p < 0.0005), which in turn correlated directly with mean (p = 0.028) and maximum (p = 0.014) wall shear stress (WSS) using Pearson's correlation coefficient, whereas aspect ratio was inversely correlated with mean (0.012) and minimum (p = 0.018) WSS. CONCLUSIONS Bifurcation angle and aspect ratio are independent predictors for aneurysm rupture. Bifurcation angle, which does not change after rupture, is correlated with hemodynamic factors including inflow coefficient and WSS, as well as rupture status. Aneurysms with the hands-up bifurcation configuration are more prone to rupture than aneurysms with other bifurcation configurations.
已经广泛研究了动脉瘤破裂的危险因素，有几个因素与破裂状态有显著相关性。几项研究表明，动脉瘤破裂后形状和血液动力学发生变化。在本研究中，作者研究了一个静态因素，即分叉角，它在破裂后不会改变，以了解其对动脉瘤破裂风险和血液动力学的影响。方法：回顾性地检索了 2008 年至 2015 年间在医院接受手术或血管内治疗的脑动脉瘤患者的数据库。获取 3D 旋转血管造影数据后，创建 3D 立体光刻模型，并使用商业可用软件进行计算流体动力学分析。对破裂组和未破裂组的患者数据（年龄和性别）、形态学因素（动脉瘤体积和最大高度、纵横比、分叉角、瓶颈比和颈部/母动脉比）和血液动力学因素（流入系数和壁面切应力）进行统计学比较。结果：本研究纳入了 71 个基底尖动脉瘤，其中 22 个破裂，49 个未破裂。单因素分析显示，纵横比、分叉角、瓶颈比和流入系数与破裂状态显著相关。Logistic 回归分析表明，纵横比和分叉角是破裂状态的显著预测因子。分叉角与流入系数呈负相关（p < 0.0005），而流入系数与平均壁面切应力（p = 0.028）和最大壁面切应力（p = 0.014）呈正相关，这是通过 Pearson 相关系数得到的，而纵横比与平均壁面切应力（0.012）和最小壁面切应力（p = 0.018）呈负相关。结论：分叉角和纵横比是动脉瘤破裂的独立预测因子。破裂后不会改变的分叉角与包括流入系数和壁面切应力在内的血液动力学因素以及破裂状态相关。具有举手分叉构型的动脉瘤比具有其他分叉构型的动脉瘤更容易破裂。
