Recurrence of macular edema in eyes with branch retinal vein occlusion changes the diameter of unaffected retinal vessels

Purpose To measure unaffected retinal vessel diameter in eyes with macular edema (ME) secondary to branch retinal vein occlusion (BRVO) after intravitreal injection with bevacizumab (IVB). Methods Patients with BRVO-induced ME who responded to IVB were assessed at baseline and 1, 3, and 6 months. In both eyes, the diameters of the largest arteriole and venule in all quadrants (except occlusion quadrant) were measured by using a computer-assisted method. The same vessels chosen at baseline were measured at each follow-up examination. Results Forty-two eyes were participated. At baseline, venular diameters of unaffected quadrants in eyes with BRVO were larger than the venules in the corresponding quadrant of the fellow eyes ( p