中文摘要：

目的应用计算流体力学（CFD）方法结合血管影像显示在体颈动脉分叉的血流动力状态.方法选取1例志愿者,采用Siemens多层螺旋CT机行左侧颈动脉CT血管成像检查（CTA）,扫描所得原始图像经计算机后处理后,用CFD方法计算并显示血液动力学各项指标.结果（1）该血管血液流率均值范围为0.04～0.36 m/s,颈外和颈内动脉的内侧壁（均以分叉顶点为参照）可见一高血流速区,球部可见较大片低血流速区;颈动脉分叉及颈内、外动脉近端均可见血液涡流与回流.（2）血液绝对压、静态压和动态压的均值范围分别为100 266.70～101 615.90 Pa、-10 58.34～290.88 Pa、6.12～553.25 Pa;（3）管壁切应力均值范围为0.59～5.35 Pa,在颈动脉球部及颈内动脉后壁显示大范围的低切应力区,最低约为0.25 Pa,颈外动脉前外侧壁存在一小范围低切应力区.结论CFD方法结合血管影像能计算并显示在体颈动脉分叉的个体化血液动力学指标.

英文摘要：

Objective To investigate the visualization and quantitation of hemodynamic variables at carotid artery bifurcation in vivo by combining computational fluid dynamics （CFD）and vascular imaging. Methods A healthy volunteer underwent CT angiagraphy of left carotid artery by SIEMENS multi-shce CT. Parameters of hemodynamics at this carotid bifurcation were calculated and visualized by combining vascular imaging post-processing and CFD. Results （ 1 ） The average range of flow velocity was 0. 04 - 0. 36 m/s. A region of high velocity was seen at medial wall of internal carotid artery （ICA） and medial wall of external carotid artery （ECA）, respectively. The largest contiguous region of low velocity occurred at the carotid bulb. （2）The average range of absolute pressure, static pressure and dynamic pressure was 100 266. 70 - 101 615.90 Pa, -1058. 34-290. 88 Pa, and 6. 12-553.25 Pa, respectively. （3） The average range of wall shear stress （WSS） at the bifurcation was 0. 59 - 5.35 Pa. There was a large region of low WSS at carotid bulb and posterior wall of ICA, with the lowest value of 0. 25 Pa. Also there was a small region of low WSS at anterior and lateral wall of ECA. Conclusion CFD combined with vascular imaging can calculate and visualize the parameters of hemodynamics at carotid bifurcation in vivo individually. It is an interdisciplinary science of computer, radiology and hemodynamics and provides a new method to investigate the relationship of vascular geometry and flow condition with atherosclerotic pathological changes.