Retinal vein occlusion (RVO) is among the leading causes of visual impairment in vascular diseases [1]. Branch retinal vein occlusion (BRVO) is the most common RVO type with an incidence of 4.4-16/1000 persons/year [2], [3]. BRVO is a venous occlusion at any branch of the central retinal vein. It occurs at arteriovenous crossing sites that share a common adventitia [4], [5]. BRVO has many known ophthalmic and systemic risk factors, including age, hypertension, hyperlipidemia, ocular hypertension, and glaucoma [1], [6], [7]. The typical funduscopic examination consists of flame hemorrhages, dot and blot hemorrhages, cotton wool spots, hard exudates, retinal edema, and dilated tortuous veins [8]. BRVO can be divided into ischemic and nonischemic subtypes according to the area of capillary nonperfusion, and this distinction affects the clinical approach [8]. The BRVO is generally considered ischemic whenever there is an area of retinal capillary non-perfusion of five-disc areas or greater on fundus fluorescein angiography (FFA) [9].

One major complication of BRVO is the development of ME in more than 90% of the eyes affected, which can cause severe visual disturbance and vision loss [10]. Today optic coherence tomography (OCT) is the best way to diagnose and evaluate ME secondary to BRVO [11]. It is especially helpful in monitoring and evaluating the treatment response [11], [12]. The ME is closely associated with increased vascular endothelial growth factor (VEGF) [13]. Anti-VEGF agents are commonly used to treat the ME, reduce the severity of anterior segment neovascularization, and lower the risk of ocular angiogenesis [14], [15]. Laser photocoagulation is a procedure that ablates nonperfusion areas [16]. One may hypothesize that coagulating nonperfused retinal areas can reduce the release of new VEGF and other factors causing a breakdown in the blood-retinal barrier, thereby reducing the need for anti-VEGF [16], [17]. Data on early laser photocoagulation in BRVO are limited.

In the current study, we planned to investigate the relationship between the treatment of peripheral non-perfused retina with early peripheral photocoagulation and the number of needed intravitreal injections in patients with BRVO with ME.