Clinical Implications of Serous Retinal Detachment in Branch Retinal Vein Occlusion and Response After Primary Intravitreal Bevacizumab Injection

Purpose: To evaluate the impact of macular serous retinal detachment (SRD) and its relationship to treatment outcome after primary intravitreal bevacizumab (IVB) injection in patients with branch retinal vein occlusion (BRVO) and macular edema (ME). Methods: Seventy-three patients with ME secondary to BRVO who received primary IVB (2.5 mg/0.1 mL) were included in this study. The specific ME patterns were investigated using optical coherence tomography (OCT) examination. Visual acuity (VA), central macular thickness (CMT), and macular volume at baseline; at 1, 3, and 6 months; and at final visit after primary IVB were retrospectively analyzed and compared between patients with and without SRD. Results: SRD was found in 25 patients (34.2%). The baseline CMT was significantly thicker in patients with SRD than in those without it (648.4 +/- 200.5 mm vs. 440.3 +/- 119.6 mm, P < 0.001). Six months after primary IVB injection, a greater reduction in CMT change from baseline was observed in the SRD group (412.5 +/- 227.2 mm) than in the group without SRD (118.5 +/- 175.2 mm) (P < 0.001). The improvement of logarithm of the minimum angle of resolution VA was also greater in the SRD group than in the group without SRD (-0.64 +/- 0.52 and -0.28 +/- 0.62 respectively, P = 0.015). Logistic regression analysis showed that the presence of SRD was an independent factor for visual improvement in BRVO (P = 0.027). Conclusion: Patients with SRD had greater functional and morphological improvements at 6 months after primary IVB therapy. The results of this study suggest that the presence of SRD observed on OCT may be an indicator of favorable clinical response after IVB injections and that in BRVO patients with SRD, bevacizumab may be a good alternative for treatment.