Center for Computational Imaging & Simulation Technologies in Biomedicine, Information & Communication Technologies Department, Universitat Pompeu Fabra, Barcelona, Spain.
AJNR Am J Neuroradiol. 2011 Nov-Dec;32(10):1935-41. doi: 10.3174/ajnr.A2635. Epub 2011 Sep 1.
Endovascular coiling is a well-established therapy for treating intracranial aneurysms. Nonetheless, postoperative hemodynamic changes induced by this therapy remain not fully understood. The purpose of this work is to assess the influence of coil configuration and packing density on intra-aneurysmal hemodynamics.
Three 3D rotational angiography images of 3 intracranial aneurysms before and after endovascular coiling were used. For each aneurysm, a 3D representation of the vasculature was obtained after the segmentation of the images. Afterward, a virtual coiling technique was used to treat the aneurysm geometries with coil models. The aneurysms were coiled with 5 packing densities, and each was generated by using 3 coil configurations. Computational fluid dynamics analyses were carried out in both untreated and treated aneurysm geometries. Statistical tests were performed to evaluate the relative effect of coil configuration on local hemodynamics.
The intra-aneurysmal blood flow velocity and wall shear stress were diminished as packing density increased. Aneurysmal flow velocity was reduced >50% due to the first inserted coils (packing density <12%) but with a high dependency on coil configuration. Nonsignificant differences (P > .01) were found in the hemodynamics due to coil configuration for high packing densities (near 30%). A damping effect was observed on the intra-aneurysmal blood flow waveform after coiling.
Intra-aneurysmal hemodynamics are altered by coils. Coil configuration might reduce its influence on intra-aneurysmal hemodynamics as the packing density increases until an insignificant influence could be achieved for high packing densities.
血管内线圈栓塞术是治疗颅内动脉瘤的成熟疗法。然而，这种治疗方法引起的术后血流动力学变化仍不完全清楚。本研究旨在评估线圈结构和填塞密度对瘤内血流动力学的影响。
使用 3 例颅内动脉瘤患者的 3 例术前和术后的 3D 旋转血管造影图像。对每个动脉瘤，通过图像分割获得血管的 3D 表示。然后，使用虚拟线圈技术，用线圈模型对动脉瘤几何形状进行治疗。将动脉瘤用 5 种填塞密度进行填塞，每种填塞密度都使用 3 种线圈结构生成。对未治疗和治疗后的动脉瘤几何形状进行计算流体动力学分析。进行了统计学检验，以评估线圈结构对局部血流动力学的相对影响。
随着填塞密度的增加，瘤内血流速度和壁面切应力降低。由于第一个插入的线圈（填塞密度<12%），动脉瘤的血流速度降低了>50%，但对线圈结构有高度依赖性。在高填塞密度（接近 30%）时，由于线圈结构导致的血流动力学差异无统计学意义（P>.01）。在栓塞后，瘤内血流波形观察到阻尼效应。
线圈改变了瘤内的血流动力学。随着填塞密度的增加，线圈结构可能会降低其对瘤内血流动力学的影响，直到填塞密度较高时，其影响变得可以忽略不计。
