Evaluation of the initial optical coherence tomography parameters in anticipating the final visual outcome of central retinal vein occlusion

Purpose: To evaluate the predictive and associated factors in determining the visual outcome in patients having central retinal vein occlusion (CRVO)-related macular edema (ME). Methods: The charts of the patients who were treated due to CRVO-related visual disturbance were reviewed. The optical coherence tomography (OCT) images of eyes were analyzed, and disorganization of retinal inner layers (DRILs), ellipsoid zone (EZ) and external limiting membrane (ELM) disruption length, hyper-reflectivity of retinal inner layer (HRIL) existence, baseline and final visual acuity (VA), subfoveal thickness (SFT), subretinal fluid (SRF), and injection numbers were noted. The regression and correlation analyses were applied. Results: Thirty eyes of thirty patients were included in the study. The mean follow-up time was 17.5 ± 11 (8-47) months. The mean baseline VA was 1.4 ± 0.7 (0.2-3.1) logMAR. A total of 87 intravitreal injections were applied for the treatment of ME during the follow-up. The initial mean central subfield thickness was 795 ± 264 (1470-398) μm. HRIL and SRF were observed in 16 and 23 eyes at the initial visit, respectively. The final mean VA was 1.2 ± 0.9 (0.1-3.1) logMAR. At the final visit, additional OCT parameters were evaluated. The mean DRIL length was 463 ± 324 μm. The mean disruption length of EZ and ELM was 367 ± 247 μm and 414 ± 327 μm, respectively. The final mean SFT was 290 ± 91 μm. SRF presence at the initial visit was found to be associated with elongated EZ and ELM disruption length at the final visit (P = 0.03 and P = 0.04, respectively). On linear regression analyses, none of the baseline features (SRF, SFT, and HRIL) except baseline poor best corrected visual acuity were found to be predictive in anticipating the final visual outcome (P = 0.04). On linear bivariate analysis, the final poor visual outcome was found to be affected by EZ disruption length of ≥500 μm at the last visit (P = 0.02). Conclusion: Baseline VA was the only predictive factor in anticipating the final visual outcome. At the final visit, extensive disruption length of EZ in the subfoveal area was associated with a poor visual outcome.