HEMORHEOLOGY IN PATIENTS WITH BRANCH RETINAL VEIN OCCLUSION WITH AND WITHOUT RISK-FACTORS

Purpose: The study was carried out to ascertain the role of blood visc osity in patients with branch retinal vein occlusion (BRVO) with and w ithout risk factors. Methods: In 292 patients with acute BRVO (mean ag e 65+/-10 years) and 292 controls matched for gender, age, and cardiov ascular risk factors, haematocrit, plasma viscosity, erythrocyte aggre gation and erythrocyte rigidity were measured. A subgroup analysis in patients with and without risk factors was performed. Results: Haemato crit and plasma viscosity values were significantly higher in BRVO pat ients than in controls, but erythrocyte rigidity and erythrocyte aggre gaton did not differ. Subgroup analysis revealed no differences in hae matocrit and plasma viscosity values between patients with and those w ithout cardioavascular risk factors. Conclusions: This study shows inc reased plasma viscosity and haematocrit values in patients with BRVO w hich are not associated with the presence of other cardiovascular risk factors. Thus, changes in blood fluidity appear to be important facto rs in the pathogenesis of BRVO.