Purpose
To investigate epiretinal membrane (ERM) abnormalities before and 3 months after ERM peeling treatment using an adaptive optics (AO) retinal camera.
Methods
AO high-resolution images of the inner retinal interface were obtained in one eye of 5 patients with ERM and 5 age-matched healthy controls. All participants underwent a full ophthalmologic examination, including a scanning laser ophthalmoscopy (SLO) and a spectral-domain optical coherence tomography (SD-OCT).
Results
Macrofolds, microfolds and hyper-reflective lines were observed in AO images of the inner retina of all eyes with ERM. Macrofolds were defined as irregular bridges of the inner retinal surface wider than 25 μm, while microfolds were approximately 5 to 10 μm wide. Macrofolds well correlated with the retinal folds seen with SLO and SD-OCT, whereas the microfolds were not detected by both retinal imaging techniques. Hyper-reflective lines, 5-10 μm wide, were diffusely spread onto the inner retinal surface and were orthogonally oriented with respect to macro- and micro-folds. Three months after surgery, the number of both micro- and macro-folds was greatly reduced, though hyper-reflective lines could be yet visualized. Occasionally, crater-like features 40-160 μm diameter, were observed. In control eyes, AO imaging showed a normal appearance of the inner retina, including the clear visualization of the nerve fiber bundles and retinal vessels. The macrofolds, microfolds and hyper-reflective lines were not seen in any case.
Conclusions
Adaptive optics imaging provides new insight into the changes of inner retinal interface in eyes with ERM at microscopic resolution. Microfolds and hyper-reflective lines of ERM have not been detected by conventional retinal imaging tools. Microfolds may correspond to micro-wrinkles of the inner retinal surface and hyper-reflective lines to micro-exudates residing within the Müller septa or degenerated neurites and/or hyalinised retinal vessels. Three month after surgery, while the number and extent of macro- and micro-folds was greatly reduced, the hyper-reflective lines were still present on the inner retinal surface.
Keywords: 550 imaging/image analysis: clinical •
688 retina •
762 vitreoretinal surgery