Epiretinal Membranes-Dr. MacCumber
Authors: MacCumber, Mathew W.1,2;Parker, Paul R.1; Zeyer, John C.1,2;
- Department of Ophthalmology, Rush University Medical Center, Chicago, IL, United States
- Illinois Retina Associates, SC, Chicago, IL, United States
Title: Segmentation Measurements and Disorganization of the Retinal Inner Layers on Optical Coherence Tomography as Pre-Operative Indicators of Visual Outcome following Vitrectomy with Epiretinal Membrane Peeling
Purpose: We have previously found that a macular domed-shaped configuration on optical coherence tomography (OCT) correlates with better visual outcome after vitrectomy with epiretinal membrane (ERM) peeling. This study assesses segmentation thickness measurements and disorganization of the retinal inner layers (DRIL) on optical coherence tomography (OCT) as predictive indicators of visual outcome in similar eyes to aid in pre-operative assessment.
Methods: A retrospective chart review of 31 eyes in 31 patients at Illinois Retina Associates which underwent pars plana vitrectomy with ERM and internal limiting membrane (ILM) peeling in the year 2015. Inclusion criteria required a pre-op Snellen visual acuity of at least 20/200, minimum follow up of one year, and complete pre-op OCT imaging including a five-line raster. For each patient, change from baseline visual acuity to one-year follow up was calculated using LogMAR equivalent and lines of vision. The vertical distance from the ILM to the inner nuclear layer (INL) and from the ILM to the outer plexiform layer (OPL) were measured on the four non-central, non-foveal cross-sections within the five-line raster, and the mean of these four values was calculated for each patient. Disorganization of the retinal inner layers (DRIL) was defined as loss of the normal distinction between the inner plexiform layer (IPL) and INL on the foveal cross-section. The results within each group were compared using a two-tailed T test.
Results: Eyes with a mean pre-op ILM to INL thickness of ≥230 μm had a mean 2.5 lines of vision gained (p=0.037) and a mean LogMAR change of -0.25 (p=0.029) as compared to eyes with <230 μm which showed a mean 0.23 lines gained and mean LogMAR change of -0.029. Pre-op visual acuity was similar in both groups, as was central macular thickness (p=0.24). Correlation between ILM to OPL thickness and vision gain was not significant. DRIL was observed in only 4 eyes (13%); its presence/absence failed to achieve significance both in lines gained (1.2 in eyes without DRIL vs. 2.1 in eyes with DRIL; p=0.54) and LogMAR (-0.1 vs. -0.2; p=0.37).
Conclusions: Mean pre-op ILM to INL thickness of ≥230 μm on macular OCT correlated with a more favorable post-operative visual result after vitrectomy for symptomatic ERM. Central macular thickness, ILM to OPL thickness and presence of DRIL did not significantly correlate with visual outcome although the number of eyes with DRIL was small in our dataset. Larger studies would help confirm these findings.