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) 2 months 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 2 months 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 ± 0.22 µm, respectively. The average CRT, ONLT, PLT, and BCVA values for the sample group 2 months after the Ozurdex injection were as follows: 299 ± 149, 211 ± 138, 77 ± 20, and 0.63 ± 0.30 µm, 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.

Low frequency ranibizumab versus dexamethasone implant for macular oedema secondary to branch retinal vein occlusion

“…Another reason may be the longer period of oedema in RNB (4.1 months) compared to DEX (2.6 months). Also, outer nuclear layer thickness was reported to be more closely correlated with vision rather than CRT . Moreover, in ischaemic BRVO resolution of macular oedema with treatment may not result in visual improvement.…”

The Analysis of Correlative Factors of Visual Acuity with Intravitreal Conbercept Injection in Macular Edema Associated with Branch Retinal Vein Occlusion

“…The normal function of the foveal photoreceptor layer may well be necessary to regain good visual function. Therefore, some researchers tried to measure the thickness of various retinal layers, in order to lay a theoretical foundation for the visual recovery of patients with macular edema [ 4 , 5 , 10 ]. In this study, we evaluated the change in various retinal layers' thickness in BRVO after conbercept injection and analyzed the correlation between them and BCVA.…”

“…Although, retinal thickness has been reduced to physiological levels successfully after regression of macular edema, the loss of photoreceptor cells may lead to limited visual recovery. Altunel et al [ 4 ] and Ota et al [ 5 ] showed that there was no correlation between CFT and BCVA after treatment. The outcome of our study in correlation between BCVA and CFT with conbercept treatment is similar to theirs.…”

Optical Quality Assessment in Patients with Macular Diseases Using Optical Quality Analysis System

“…The photoreceptor outer segment is thinner in patients with diabetic macular edema compared to the controls or patients with DR without macular edema [15]. In eyes with macular edema secondary to RVO, the photoreceptor layer thickness is associated with visual function [16]. Furthermore, photoreceptor loss occurs in AMD [17].…”