糖尿病合并高血压的眼和视网膜动脉血流动力学特点

Hemodynamic characteristics of ocular artery and central retinal artery in diabetics with hypertension

目的揭示糖尿病伴高血压患者的眼和视网膜中央动脉血流动力学改变的特点。方法应用彩色多普勒血流成像技术,测量高血压、糖尿病、糖尿病高血压及正常对照者眼动脉和视网膜中央动脉的血流参数。结果高血压组的眼动脉血流速度和搏动指数,糖尿病组的眼动脉舒张末期血流速度、血管内径、和血管横断面积,糖尿病高血压组的眼动脉平均血流速度,均明显高于对照组;糖尿病高血压组的视网膜中央动脉舒张末期血流速度比高血压组显著下降,而视网膜中央动脉阻力指数明显增加;眼动脉血流速度及血流量比糖尿病组显著增加。结论糖尿病高血压患者的眼和视网膜中央动脉血流动力学改变,既呈现血流速度明显加快,又有血流灌注阻力增加的特征。糖尿病所致的视网膜循环阻力增加和高血压所致的视网膜血流灌注压下降,二者作用叠加模式使视网膜循环血量降低,早期就出现视网膜缺血性改变。糖尿病未发生视网膜病变前应用血管扩张药预防性治疗,比较治疗前后视网膜中央动脉的舒张末期血流速度和血管阻力指数来观察疗效。糖尿病伴高血压或动脉硬化者,可考虑用治疗前后视网膜中央动脉的收缩期峰值血流速度和血管搏动指数,和首次提出的视网膜中央动脉与眼动脉血流速度比值,作为疗效观察指标。

Objective To reveal the hemodynamic characteristics of ocular artery(OA)and central retinal artery(CRA)in diabetics with hypertension. Methods The hemodynamic parameters of OA and CRA were measured with color doppler imaging in hypertension,diabetics,diabetics with hypertension,and control groups. Results The blood velocities and pulsate index of OA in hypertension group,the end diastolic velocity and diameter of OA in diabetics group,the average velocity of OA in diabetics with hypertension group were significantly increased,compared to those in control group.The end diastolic velocity of CRA was lower as well as the resistance index of CRA in diabetics with hypertension group was higher than those in hypertension group.The blood velocities and volume of OA in diabetics with hypertension group significantly increased compared to diabetics group. Conclusions The hemodynamic characteristics of OA and CRA in diabetics with hypertension were the increases of blood velocity due to hypertension and the decrease of blood resistance.due to diabetic.Both result in retinal ischemia that occurs earlier.According to the results of this study,the increase of end diastolic velocity and the decrease of resistance index in CRA should be therapeutical indicators for diabetics.And,the decrease of peak systolic velocity and pulsate index of CRA should be therapeutical indicators for diabetics with hypertension.At the first time,the velocity ratio of CRA to OA as indicator to present the flow resistance of CRA comparing to that of OA was introduced.These parameters could indicate the effects of vascular dilatation therapy for preventing retinal proliferation.