Materials and Methods: The BRVO patient cohort comprised 25 eyes of 25 patients (group 1). Intact contralateral eyes of these patients were considered control eyes (group 2), and 26 individuals with no ocular or systemic disease were enrolled as a control group (group 3). AL and ACD of all patients were measured by A-mode ultrasonography. Horizontal disc diameter (HDD) and vertical disc diameter (VDD) of all patients were measured using a color fundus photograph.

Results: There was no significant difference between the groups according to age or sex distribution (p=0.454, and p=0.542, respectively). A significant difference was found in AL values between group 1 (21.92±0.62 mm) and 2 (23.02±0.75 mm) (p=0.001), and between group 1 and 3 (23.42±0.73 mm) (p=0.001). There was no significant difference between group 2 and 3 (p=0.072). A significant difference was present in ACD values between group 1 (2.97±0.43 mm) and 3 (3.43±0.36 mm), and between group 2 (3.01±0.4 mm) and 3 (p=0.001), while no significant difference was found between group 1 and 2 (p=0.918). VDD values differed significantly between group 1 (1.76±0.15 mm) and 2 (1.90±0.14 mm) (p=0.019), and between group 1 and 3 (1.96±0.19 mm) (p=0.001), but there was no significant difference between group 2 and 3 (p=0.663). HDD values did not differ significantly between group 1 (1.74±0.12 mm) and 2 (1.77±0.16 mm) (p=0.954), or between group 2 and 3 (1.86±0.20 mm) (p=0.115), but there was a significant difference between group 1 and 3 (p=0.020). ACD/AL ratio was significantly different between group 1 and 3, and between group 2 and 3 (p=0.029, p=0.001, respectively).

Conclusion: The presence of short axial length associated with small optic disc diameter (especially vertical) is a risk factor in terms of BRVO. Keywords : Branch retinal vein occlusion, axial length, anterior chamber depth, optic disc diameter.