Fluid-induced wall shear stress in anthropomorphic brain aneurysm models: MR phase-contrast study at 3 T
Fluid-induced wall shear stress in anthropomorphic brain aneurysm models: MR phase-contrast study at 3 T
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DOI：
10.1002/jmri.20928
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发表时间：
2007-06-01
影响因子：
4.4
通讯作者：
Sinha, Shantanu
中科院分区：
文献类型：
--
作者：
Ahn, Sinyeob;Shin, Dongsuk;Sinha, Shantanu
目的：利用磁共振相位衬度成像（MR-PC）研究颅内动脉瘤模型的壁面切应力（WSS）的时空分布，并与激光多普勒测速仪（LDV）的结果进行比较。材料与方法：高分辨率MR-PC成像是在动脉瘤模型上进行的，该模型是根据基底动脉（BA）尖端和大脑中动脉（MCA）动脉瘤。WSS通过使用图像后处理技术计算剪切应变率来测量。WSS的特点是使用几个参数，包括平均WSS和振荡剪切指数（OSI）。BA头端中的气泡区域和MCA动脉瘤中的圆顶区域在一个小的局部区域内持续暴露于高WSS，与其他动脉瘤区域相比，空间变化大，时间变化小。结论：MR-PC成像与LDV研究结果具有良好的一致性，可用于颅内动脉瘤模型的血流动力学研究。WSS的特征模式，如高空间变化和时间变化的情况下，结合局部增加的高WSS由MR-PC成像确定，可以阐明WSS的影响，脑血管瘤的发展和破裂。
Purpose: To study spatial and temporal distribution of wall shear stress (WSS) of intracranial aneurysm models using magnetic resonance phase contrast (MR-PC) imaging, and to compare results to those obtained in our previous study using laser Doppler velocimetry (LDV).Materials and Methods: High-resolution MR-PC imaging was performed on aneurysm models created from 3D in vivo data of a basilar artery (BA) tip and a middle cerebral artery (MCA) aneurysm. WSS was measured by calculating the rate of shearing strain using image postprocessing techniques. WSS was characterized using several parameters, including average WSS and oscillatory shear index (OSI).Results: Both aneurysms showed the highest WSS at an ostium. A bleb region in the BA tip and a dome region in the MCA aneurysm were consistently exposed to high WSS within a small local area with high spatial variation and little temporal change in comparison to other aneurysmal regions. High correlation was noted for the spatial distribution at the peak systole between the MR-PC and the LDV studies, with the correlation coefficient value of 77% to 81%.Conclusion: MR-PC imaging showed good agreement with the reference LDV study, confirming its potential to study hemodynamics of physiologically realistic in vitro intracranial aneurysm models. Characteristic patterns of WSS, such as high spatial variation and absence of temporal variation, combined with locally increased high WSS as determined by MR-PC imaging, may elucidate the effect of WSS on aneurysmal development and rupture.