Abstract:Objective To determine the effect of essential hypertension (EH) with different risk stratification on the morphology and function of bulbar conjunctival microcirculation in EH patients. Methods Blood pressure (grades 1, 2, and 3), other cardiovascular risk factors (age, smoking, blood cholesterol, low density lipoprotein cholesterol, high density lipoprotein cholesterol, family history of premature cardiovascular diseases, body mass index, and high sensitivity C reactive protein), and target organ damage and complications were used to stratify 118 EH patients admitted in the hypertension clinic of our hospital from April 2014 to February 2015. Bulbar conjunctival microcirculation was monitored and analyzed in the patients and 20 healthy volunteers in the same period. Results Compared with the healthy volunteers, the low-risk patients had statistically sparser grid structure, less microvessels, and thinner venules (P<0.05). While the moderate-, high-, and very high-risk patients displayed obvious changes in morphology, blood flow in microvessles, and surrounding loop state. The morphological changes were mainly characterized by blurred vision, reduced microvessels, thinner arterioles and venules, more microvessels of uneven diameters, grid structure and microaneurysm, cystic dilation and ischemic area. They also showed slowed blood flow velocity, increased erythrocyte aggregation and exudation, and hemosiderin deposition in surrounding loop. With the increase in risk stratification, there were gradually more grid structure density, decreased number of microvessels, reduced blood flow velocity, and enhanced erythrocyte aggregation (P<0.05). Conclusion EH patients with different risk stratification show different alterations in bulbar conjunctival microcirculation.