颈动脉粥样硬化对视网膜中央动脉血流动力学的影响

目的阐明颈动脉粥样硬化下视网膜中央动脉的血流动力学改变特点及影响因素。方法应用彩色多普勒血流成像技术，测量了颈动脉粥样硬化组及正常对照组的颈总动脉、颈内动脉、眼动脉、和视网膜中央动脉的血流动力学参数，颈总和颈内动脉内膜-中层厚度与硬化斑块大小。结果颈动脉粥样硬化组视网膜中央动脉的收缩期峰值和舒张末期血流速度显著降低，呈低速正常阻力型。视网膜中央动脉血供与颈总和颈内动脉的检测参数相关。视网膜中央动脉收缩期峰值和舒张末期血流速度比分组分析显示不同组间的颈动脉内膜-中层厚度与硬化斑块大小有明显差异。结论颈动脉粥样硬化后。受血管调节功能异常，血管分级血流调节和动脉结构重构的综合影响，视网膜中央动脉血液供应减少。对严重颈动脉狭窄者，详细检查视神经视网膜功能，可早期发现缺血性视神经视网膜病变。同样，缺血性视神经视网膜病变者。应检测颈总和颈内动脉，视网膜中央动脉血流动力学参数。明显狭窄者，可能伴有脑部缺血性疾病。需考虑颈动脉手术治疗。检测结果有助于鉴别病变的可能病因和观察疗效。

Effects of carotid atherosclerosis on hymodynamics of central retinal artery

Objective To evaluate the hymodynamic characteristics of central retinal artery(CRA)in carotid atherosclerosis.Methods Forty-three cases with clinical suspect of carotid atherosclerosis and 19 age-matched normal controls were examined with color Doppler flow imaging.The internal diameter,intima-media thickness(IMT),the size of plaque of carotid of common carotid artery(CCA)and internal carotid artery(ICA)as well as hymodynamic parameters of CCA,ICA,ocular artery,and CRA were measured.Results Both peak systolic velocity and end diastolic velocity of CRA in patients with carotid atherosclerosis were significantly reduced.The decrease was related to progression of carotid atherosclerosis.Groups divided by ratio of peak systolic velocity to end diastolic velocity of CRA were significantly different in IMT and plaque size of CCA and ICA.Conclusions Although the compensation of vascular modification and artery remodeling,the blood supply of CRA was decreased under the effects of carotid atherosclerosis.In patients with severe progression of carotid atherosclerosis,examining retinal and visual nerve function is important for predicting the occurrence of retinal or visual nerve ischemia.On the other hand,detecting the hymodynamic changes of carotid and ocular arteries could help to indicate cerebral ischemia in patients with retinal or visual nerve ischemia.Carotid endarterectomy and percutaneous transluminal angioplasty might be a new method to treat retinal or visual nerve ischemia with severe progression of carotid atherosclerosis.