Evaluation of foveal photoreceptor layer in eyes with macular edema associated with branch retinal vein occlusion after ozurdex treatment.

Abstract

The aim of this study was to evaluate the central retinal thickness (CRT), outer nuclear layer thickness (ONLT), photoreceptor layer thickness (PLT), photoreceptor layer integrity, and the correlation between visual acuity and PLT in eyes with branch retinal vein occlusion (BRVO) 2months after treatment with intravitreal dexamethasone implant (Ozurdex; Allergan, Inc, Irvine, CA). In this prospective study, 32 eyes of 32 patients were enrolled. A single injection of Ozurdex was administered to all the patients. CRT, ONLT, and PLT were measured using spectral-domain optical coherence tomography before and 2months after the injection. Best-corrected visual acuity (BCVA [logMAR]) and photoreceptor cell integrity were also evaluated. The average CRT, ONLT, PLT, and BCVA values for the sample group before the treatment were as follows: 707±261, 608±288, 70±25, and 0.96±0.22µm, respectively. The average CRT, ONLT, PLT, and BCVA values for the sample group 2months after the Ozurdex injection were as follows: 299±149, 211±138, 77±20, and 0.63±0.30µm, respectively (p<0.05). Two months after the Ozurdex injection, BCVA correlated with ONLT and PLT (r=0.365, p=0.048 and r=-0.488, p=0.021, respectively), whereas BCVA was not correlated with CRT (r=0.239, p=0.189). Photoreceptor layer is associated with the visual function of eyes with macular edema secondary to BRVO. Also, ONLT seems to be more closely related to visual acuity improvement than CRT decrement.