目的　探讨单纯性肥胖症是否引起青少年脑血流动力学改变以及改变原因。方法　分别测量 17例肥胖青少年与 18例同身高、同性别正常体重青少年的血压、血液流变学指标 (总胆固醇、甘油三酯、剪切率为30 0S-1、5S-1、1S-1下的全血粘度、血浆粘度和红细胞变形性 )和脑血流动力学指标 (收缩期峰流速、舒张期末峰流速、平均峰流速、脉动指数 ) ,进行组间比较和相关分析。结果　肥胖青少年的血压、血脂和低剪切率下全血粘度等明显高于非肥胖者 ;肥胖青少年的脑血流动力学指标 :收缩期峰流速、舒张期末峰流速、平均峰流速均低于正常对照组 ,相关分析表明 ,这是血压和血液流变学异常的综合现象 ,反映脑血管弹性的脉动指数两组间无差异。结论　肥胖青少年由于血压、血液流变学的异常 ,导致脑血流速度、区域脑血流量下降 ,但其脑血管弹性正常 Objective To investigate whether simple obesity causes cerebral hemodynamics and causes in adolescents. Methods Blood pressure and hemorheology indexes (total cholesterol, triglyceride, shear rate of 30 0S-1, 5S-1, 1S-1) in 17 obese adolescents and 18 adolescents with the same- (Whole blood viscosity, plasma viscosity and erythrocyte deformability) and cerebral hemodynamic parameters (peak systolic velocity, peak diastolic velocity, average peak velocity, pulsatility index) were compared between groups and correlation analysis. Results Compared with non-obese subjects, obese adolescents had significantly lower blood pressure, blood lipids and whole blood viscosity at low shear rate. The indexes of cerebral hemodynamics in obese adolescents were as follows: the peak systolic velocity, the peak diastolic velocity and the average peak velocity were lower than The normal control group, correlation analysis showed that this is a combination of abnormal blood pressure and blood rheology, reflecting the pulse of cerebral vascular elasticity index no difference between the two groups. Conclusion Obese adolescents, due to abnormal blood pressure and hemorheology, lead to decreased cerebral blood flow velocity and regional cerebral blood flow, but their cerebrovascular elasticity is normal