颈内-后交通动脉瘤破裂危险的形态学与血流动力学分析

目的用数值模拟的方法分析颈内-后交通动脉瘤破裂危险相关的形态学与血流动力学因素。方法选择2011年1月至12月在第二军医大学长海医院神经外科接受血管造影的颈内-后交通动脉瘤39枚,其中破裂动脉瘤28枚,未破裂动脉瘤11枚。重建三维脑血管造影影像获得动脉瘤模型,测量其形态学参数,并应用计算流体力学方法分析动脉瘤的血流动力学特征。结果破裂组瘤高/颈宽比(AR)为1.233±0.483,高于未破裂组(0.832±0.252,P=0.002);破裂组标准化壁面切应力(WSS)为0.545±0.259,低于未破裂组(0.761±0.216,P=0.015);破裂组低壁面切应力面积(LSA)为(11.669±16.041)%,高于未破裂组(1.236±2.212)%,P=0.040]。其余指标,包括瘤体/载瘤血管直径比(SR)和剪切震荡指数(OSI)在两组间差异无统计学意义。结论高AR值、低WSS和高LSA可能是影响颈内-后交通动脉瘤破裂的危险因素。

Rupture risks of posterior communicating artery aneurysms: morphological and hemodynamic analysis

Objective To use numerical simulation technology for analyzing the hemodynamic and morphological factors for rupture status of posterior communicating artery aneurysms. Methods A total of 39 posterior communicating artery aneurysms treated in Changhai Hospital were recruited in the present study during January to December 2011, and they included 28 ruptured and 11 unruptured ones. The 3-dimensional model of the aneurysms were constructed, and the digital subtraction angiography data were obtained. Then the hemodynamic analysis of the aneurysms was done using the method of computational fluid dynamics. Results The aspect ratio (AR) was 1.233±0.483 in the ruptured group, which was significantly higher than that in unruptured group (0.832±0.252, P=0.002). The normalized mean wall shear stress (WSS) was significantly lower in ruptured group than in unruptured group (0.545±0.259 vs 0.761±0.216, P=0 .015). And the percentage of the low WSS area (LSA) in ruptured group was significantly higher than that in unruptured group (\11.669±16.041\]% vs \1.236±2.212\]%, P=0.040). Other parameters, including size ratio (SR) and oscillatory shear index (OSI), showed no significant differences, between the two groups. Conclusion Higher AR, lower WSS and higher LSA may be risk factors for aneurysmal rupture.