This was a 60-year-old female referred to our center from another clinic. The patşent had hypertension and it was learnt that she underwent three intravitreal anti-VEGF injections. The BCVAs were 20/30 in the right eye and 20/20 in the left eye. The IOPs were within normal limits and anterior segment examination was unremarkable.
Fundus images of the right eye showed retinal hemorrhages and cotton wool spots in superior temporal quadrant of the retina in addition to collateral vessels (in the wihte circles) and abnormal foveal reflex and edema. The left eye had a normal fundus appearance.
Fundus fluorescein angiography exhibited the widespread collateral vessels and macular ischemia in the superior temporal of macula in the rigt eye while the left eye was normal.
Optical coherence tomography of the right eye demonstrated intraretinal cysts with minimal serous foveal detachment.
Branch retinal vein occlusion (BRVO) has many known ophthalmic and systemic risk factors such as age, hypertension, hyperlipidemia, ocular hypertension, and glaucoma. Collateral vessels represent a frequently observed sequela after central or branch retinal vein occlusion. The development of collateral vessels is currently interpreted as the result of hemodynamic factors and hydrostatic pressure, leading to the opening of collateral channels that originate from the pre-existing capillary network and provide vein-to-vein drainage. The collateral vessels in BRVO form as result of capillary dropout and are considered to represent remodeling of the retinal capillaries. It was also showed that the presence of collateral vessels around the fovea in patients with BRVO may be good indicators of persistent macular edema.
Credit: Kemal Tekin, M.D., from Ulucanlar Eye Training and Research Hospital
Instagram accounts: @retina.academy and @dr.kemaltekin