Does Glaucoma Share Common Pathogenesis with Branch Retinal Vein Occlusion?

Background To evaluate the observed prevalence and the optic nerve head (ONH) characteristics of normal tension glaucoma (NTG)-suspect eyes in branch retinal vein occulusion (BRVO) eyes in Korean population. Methods This was a retrospective observational study. We investigated 445 BRVO eyes that were diagnosed in the retina clinic of Samsung Medical Center between March 2005 and December 2011. The observed prevalence of NTG-suspect in BRVO eyes was evaluated compared to the previous population based study. In addition, NTG-suspect cases in BRVO were divided into three groups based on the characteristics of optic disc morphology. Results In 445 BRVO eyes, 30 eyes were excluded from the present study. In 415 BRVO eyes, 4.3% (18 eyes) (95% confident interval [CI], 2.4-6.3%) were diagnosed with suspect glaucoma and this is not significantly different from the result in the general Korean population (P = 0.09). We classified the NTG-suspect eyes into three groups such as disc rim notching and thinning type (Group 1; 55.6%), optic cup-sited hemorrhage type (Group 2; 16.7%) and disc rim thinning and pallor type (Group 3; 27.8%). NTG-suspect in the fellow eye were only found in group 1 (80%) and group 2 (67%), but not in group 3 (P = 0.01). Conclusions BRVO and glaucoma seem to have no common vascular pathogenesis in consideration of the prevalence of NTG-suspect in BRVO eyes compared to general Korean population.