摘要
目的:保证研究对象的椎动脉在正常体位下,即保证研究对象没有向前或向后发生椎动脉过度拉伸或弯曲的情况下,采集临床CTA图像,应用三维重构方法构建体外人体真实椎动脉并应用计算流体力学方法进行血流动力学数值模拟,比较不同研究对象椎动脉的血流动力学参数,分析椎动脉狭窄与血流动力学的关系。方法:研究对象A椎动脉在基底动脉之前部分出现狭窄;研究对象B椎动脉正常。采集的临床CTA图像均为Dicom格式,层间距为0.5 mm,每片图像的平面分辨率为512×512,像素大小为0.5 mm。应用医学图像后处理软件Simpleware对CTA二维医学图像据进行处理得到人体椎动脉三维立体模型。将椎动脉三维立体模型导入到CFD软件中进行前处理、网格划分和数值模拟。结果:通过瞬态模拟计算,得到了椎动脉在心动周期内不同时刻的血流动力学参数。结论:通过对比两个不同个体的血流动力学参数来分析椎动脉内血流动力学参数与椎动脉狭窄的关系,发现椎动脉狭窄血流动力学因素(如低流速、低壁面切应力、高振荡壁面切应力)可以诱发和加速与动脉粥样硬化及血栓的形成,为进一步研究椎动脉狭窄等疾病的发病机理提供理论支持。
Objective Ensuring the normal position of the vertebral artery in the research objects, that is to say, the object could not move forward or backward to over stretch or flex the vertebral artery. Then collecting clinical CTA images and building the real human vertebral artery in vitro by three-dimensional reconstruction. Also, performing the numerical simulation of hemodynamics by computation fluid dynamic. We used all these ways to compare hemodynamics parameters of different vertebral arteries in different objects and analyze the relation between vertebral artery stenosis and hemodynamics. Methods Setting object A with part of vertebral artery stenosis ending with the basilar artery; As for object B, setting it normal. Clinical CTA images will be in DICOM format, layer distance 0.5 mm, plane resolution 512 x 512 and pixel size 0.5 mm. To get the human vertebral artery three-dimensional model after the CTA two-dimensional images processing by a medical image post-processing software Simpleware. Then import the model to the CFD software and pre-process, mesh and numerically simulate the model. Results Acquired the hemodynamics parameters of vertebral artery within cardiac cycle in different periods by transient simulation. Conclusion By comparing two kinds of hemodynamic parameters, we analyzed the relation between the vertebral artery stenosis and hemodynamics and discovered that the hemodynamic factors （such as low flow rates, low wall shear stress, high oscillation wall shear stress） of vertebral artery stenosis could induce and accelerate atherosclerosis and thrombosis. This research will provide further study of the pathogenesis in diseases such as vertebral artery stenosis with theoretical support.
出处
《中国医学物理学杂志》
CSCD
2015年第1期110-114,共5页
Chinese Journal of Medical Physics
基金
国家自然科学基金(G81273511)
关键词
椎动脉
血流动力学
非牛顿流体
计算流体力学
壁面切应力
vertebral artery
hemodynamics
non-newtonian fluid flow
computational fluid dynamics
wall shear stressnon-newtonian fluid flow
computational fluid dynamics
wall shear stress
