Macular dynamics and visual acuity prognosis in retinal vein occlusions - ways to connect

Background and Objectives: This study aimed to establish possible connections between macular dynamics, various macular features, and visual acuity prognosis among patients with retinal vein occlusions. Materials and Methods: This study included 85 patients with central retinal vein occlusions (CRVO) and 26 with branch retinal vein occlusions (BRVO). We assessed macular features such as central macular thickness (CMT), foveal intraretinal hemorrhage (IRH), the presence and distribution of hyperreflective foci (HF), ellipsoid zone (EZ) disruption, inner retinal layer disorganization (DRIL), and posterior vitreous detachment (PVD), as well as their dynamics over one year of observation and their impact on final visual acuity prognosis, depending on the type of occlusion. Results: Best corrected visual acuity (BCVA) evolution is statistically significant regarding groups of age and type of occlusion and insignificant regarding gender. The best response to intravitreal treatment, quantified as a decrease in CMT, was registered after the first intravitreal injection. Connecting a decrease in CMT with BCVA improvement, we did not register a statistically significant correlation in the CRVO group, only in BRVO cases. The study results showed that complete PVD plays a significant positive role in decreasing CMT and BCVA improvement in cases of CRVO. Our study revealed that no matter the type of occlusion, the presence of foveal IRH will have a negative impact on the BCVA outcome. Statistically significant differences have been noted only for the evolution of visual acuity in non-ischemic CRVO cases, in correlation with the presence of EZ disruption. Outer retinal layer HF has proved to be a predictive factor for poor visual acuity outcomes. Conclusions: The most important non-imaging predicting factors regarding BCVA after retinal vein occlusions are age and baseline BCVA. CMT's dynamics still establish a weak connection with visual acuity fluctuations. The presence of foveal IRH, outer retinal layer HF, and foveal EZ disruption has a negative impact on visual acuity outcomes. Abbreviations: CRVO = central retinal vein occlusions, BRVO = branch retinal vein occlusions, CMT = central macular thickness, IRH = foveal intraretinal hemorrhage, HF = hyperreflective foci, EZ = ellipsoid zone disruption, DRIL = inner retinal layer disorganization, PVD = posterior vitreous detachment, BCVA = best corrected visual acuity, OCT = optical coherence tomography, BCVA Ti = best corrected visual acuity at first, BCVA Tf = best corrected visual acuity after one year, NR of IVI = number of intravitreal injections, SD = standard deviation, M = male, F = female, CMT Ti = central macular thickness at first, CMT T1 = central macular thickness after first injection, CMT T3 = central macular thickness after 3 injections, CMT Tf = central macular thickness after one year.