Liu Jian, Fan Jixing, Xiang Jianping, Zhang Ying, Yang Xinjian
Department of Interventional Neuroradiology, Beijing Neurosurgical Institute and Beijing Tiantan Hospital, Capital Medical University, Beijing, China.
Departments of Neurosurgery, and Mechanical and Aerospace Engineering, Toshiba Stroke and Vascular Research Center, University at Buffalo, The State University of New York, Buffalo, New York, USA.
J Neurointerv Surg. 2016 Apr;8(4):367-72. doi: 10.1136/neurintsurg-2014-011577. Epub 2015 Feb 4.
Post-ruptured intracranial aneurysm geometry models have been widely used in computational fluid dynamic studies to assess hemodynamic parameters associated with aneurysm rupture. However, their results may not be valid due to the morphological changes of the aneurysm after rupture. Our aim was to identify the hemodynamic features of aneurysms prior to rupture in comparison with unruptured aneurysms.
We retrospectively identified three large unruptured internal carotid artery (ICA) aneurysms (pre-ruptured group) with adequate image quality just before rupture. Matched with the same location and similar size, eight unruptured aneurysms (unruptured group) were selected as controls during the same time period. Flow simulations for these aneurysms were performed to compare differences in hemodynamics.
Compared with unruptured aneurysms, pre-ruptured aneurysms had a significantly more irregular aneurysm shape, a higher aspect ratio, and lower aneurysm averaged wall shear stress (WSS) (p=0.024, p=0.048, and p=0.048, respectively). Although pre-ruptured aneurysms had a lower low WSS area and higher Oscillatory Shear Index, these were not statistically significant.
For large unruptured ICA aneurysms, low WSS, higher aspect ratio, and irregular shape were indicators of fatal rupture. Early treatment for such lesions with flow diverter and coils may be the best therapeutic option.
颅内动脉瘤破裂后的几何模型已广泛应用于计算流体动力学研究，以评估与动脉瘤破裂相关的血流动力学参数。然而，由于破裂后动脉瘤的形态变化，其结果可能无效。我们的目的是确定破裂前动脉瘤与未破裂动脉瘤相比的血流动力学特征。
我们回顾性地确定了三个在破裂前图像质量良好的大型未破裂颈内动脉（ICA）动脉瘤（破裂前组）。在同一时期，选择了八个位于相同位置且大小相似的未破裂动脉瘤（未破裂组）作为对照。对这些动脉瘤进行血流模拟，以比较血流动力学的差异。
与未破裂动脉瘤相比，破裂前动脉瘤的瘤体形状明显更不规则，长宽比更高，瘤体平均壁面切应力（WSS）更低（分别为p = 0.024、p = 0.048和p = 0.048）。尽管破裂前动脉瘤的低WSS面积较小，振荡剪切指数较高，但这些差异无统计学意义。
对于大型未破裂的颈内动脉动脉瘤，低WSS、较高的长宽比和不规则形状是致命破裂的指标。对于此类病变，早期采用血流导向装置和弹簧圈治疗可能是最佳治疗选择。
