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用彩色多普勒血流显像对正常人视网膜中央动脉血流动力学研究 被引量:2
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作者 富京山 赵立安 +5 位作者 张文凯 廖盛日 张颖 吕永顺 甘丽云 凌广花 《北京医科大学学报》 CSCD 1997年第1期59-61,共3页
目的:观察正常人视网膜中央动脉(centralretinalartery,CRA)血流动力学生理变化并建立CRA血流参数正常值。方法:彩色多普勒血流显像检查100例正常人CRA血流,测定收缩期血流速度(vmax)、舒张末期血流速度(vmin)、平均血流速度... 目的:观察正常人视网膜中央动脉(centralretinalartery,CRA)血流动力学生理变化并建立CRA血流参数正常值。方法:彩色多普勒血流显像检查100例正常人CRA血流,测定收缩期血流速度(vmax)、舒张末期血流速度(vmin)、平均血流速度(Vmean)、搏动指数(PI)、阻力指数(RI)及S/D((vmax/(vmin)。结果;得到不同年龄正常人CRA血流参数,显示CRA血流速度(vmax、vmin及vean)随年龄增加而降低(P<0.01、P<0.01及P<0.01),CRA平均血流速度(vmen)右眼大于左眼(P<0.01),男性CRA血流PI、RI及S/D大于女性(均为P<0.05)。结论:正常人CRA血流参数在不同年龄、不同性别及两眼间均有显著变化。 展开更多
关键词 视网膜 血动动力学 超声波诊断
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0D-1D coupling model and 3D fluid-structure interaction model based on coronary CT angiography for displaying hemodynamic characteristics of coronary artery stenosis
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作者 LIU Shanfeng LU Xiaochen +1 位作者 TIAN Hao WU Huiqun 《中国医学影像技术》 CSCD 北大核心 2024年第8期1236-1241,共6页
Objective To observe value of 0D-1D coupling model and 3D fluid-structure interaction(FSI)model based on coronary CT angiography(CCTA)for displaying hemodynamic characteristics of coronary artery stenosis.Methods Base... Objective To observe value of 0D-1D coupling model and 3D fluid-structure interaction(FSI)model based on coronary CT angiography(CCTA)for displaying hemodynamic characteristics of coronary artery stenosis.Methods Based on CCTA data of the stenosed left anterior descending branch(LAD)in a patient with coronary heart disease,an 0D-1D coupling model and 3D FSI model were built,respectively.Then hemodynamic characteristic indexes,including the pressure,flow velocity and wall shear stress(WSS)were obtained in every 0.01 s during 1 s at 5 sampling points(i.e.sampling point 1—5)using these 2 models,respectively,and the consistencies of the results between models were evaluated with Spearman correlation coefficient r s.Results The time consuming for construction of 0D-1D coupling model and 3D FSI model was 0.033 min and 704 min,respectively.Both models showed basically distribution of the pressure,flow velocity and WSS of the stenosed LAD.For more details,the pressure at the stenosed segment of LAD and the proximal segment of stenosis were both higher,which gradually decreased at the distal segment of stenosis,and the flow velocity at the proximal segment of stenosis was in a relatively slow and uniform condition,with significantly increased flow velocity and WSS at the stenosed segment.Compared with 3D FSI model,0D-1D vascular coupling model was relatively unrefined and lack of distal flow lines when displaying blood flow velocity.For sampling point 2 at the stenosed segment of LAD,no significant consistency for pressure between 2 models was found(P=0.118),but strong consistency for the flow velocity and WSS(r s=0.730,0.807,both P<0.05).The consistencies of pressure,flow velocity and WSS between 2 models at the proximal and distal segment of stenosis,i.e.1,3—5 sampling points were week to moderate(r s=0.237—0.669,all P<0.05).Conclusion 0D-1D coupling model exhibited outstanding computational efficiency and might provide relatively reasonable results,while 3D FSI model showed higher accuracy for details and streamline when simulating LAD stenosis. 展开更多
关键词 coronary stenosis HEMODYNAMICS coronary angiography tomography X-ray computed
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