Investigative Ophthalmology & Visual Science
Surface-Specific Internal Limiting Membrane Biomechanics in Epiretinal Membrane Severity and Visual Outcomes
By Changsik Yoon, Sangkyung Choi, 윤예슬 and 4 others.
Abstract
Purpose
To determine whether surface-specific biophysical properties of the internal limiting membrane (ILM), measured by atomic force microscopy (AFM), are associated with optical coherence tomography (OCT)–based epiretinal membrane (ERM) stage and six-month visual outcomes.
Methods
In this prospective study, ILM specimens from vitrectomy for idiopathic ERM (stages 2–4) were examined by AFM for thickness, roughness, stiffness, and adhesion on the vitreal or retinal surface. AFM parameters were related to preoperative OCT parameters, best-corrected visual acuity, surgical grade of ILM adherence, and six-month outcomes. Multivariable regression assessed correlates of visual change and final acuity.
Results
We analyzed 147 eyes (80 retinal-side, 67 vitreal-side). Retinal-side roughness and stiffness exceeded vitreal-side values (both P < 0.001). Retinal-side roughness and adhesion (P < 0.001 and P = 0.008, respectively) and, less strongly, vitreal-side stiffness (P = 0.035) increased with ERM stage, whereas vitreal-side adhesion did not. Thickness did not differ by surface or stage (all P ≥ 0.116). Retinal-side roughness and adhesion correlated with preoperative severity and postoperative outcomes, whereas vitreal-side stiffness correlated mainly with severity and vitreal-side adhesion with surgical adherence. Greater retinal-side adhesion and vitreal-side stiffness were associated with smaller visual gains and worse final acuity in multivariable models (all P < 0.05).