Session Title: Free Paper Session 6: Vitreoretinal Surgery II
Session Date/Time: Thursday 07/09/2017 | 14:30-16:00
Paper Time: 15:42
Venue: Room 111
First Author: : D.Compera GERMANY
Co Author(s): : F. Hagenau A. Wolf S. Priglinger R. Schumann
To characterize epimacular tissue that is hyporeflective on SD-OCT and presents a yellowish appearance during macular surgery. Hyporeflective epimacular tissue was described to be situated on the macular surface of eyes with different traction maculopathies, with a particular high incidence in lamellar macular holes.
Interventional laboratory investigation.
Hyporeflective epimacular tissue was removed from 20 eyes during standard vitrectomy. We harvested specimens from 10 eyes with idiopathic macular pucker (iMP), 4 eyes with macular pseudoholes (MPH), 3 eyes with lamellar macular holes (LMH) and 3 eyes with full-thickness macular holes (FTMH). Specimens were prepared as flat mounts for fluorescence microscopy, phase contrast and interference microscopy, and immunocytochemistry. Ultrathin sections were prepared for transmission electron microscopy. Immunocytochemical staining was performed with primary antibodies directed against myofibroblasts, glial cells and hyalocytes.
Using flat-mount preparation, surgically removed epimacular tissue showed a positive autofluorescence under the fluorescence microscope. Using immunohistochemistry, glial cell markers such as anti-glutamin synthetase and anti-vimentin were strongly positive but not co-localized. Myofibroblasts with positive anti-alpha-SMA staining were detected. Anti-melan A and anti-melanopsin were negative. Electron microscopy revealed densely packed epiretinal cell proliferation with vitreous collagen strands. Ultrastructural observations show autofluorescent pigment cells with granules in the cytoplasm.
Presence of autofluorescent pigment cells explains the yellowish appearance of hyporeflective epimacular tissue in eyes with different traction maculopathies during macular surgery. Our data were suggestive of a lipo-pigment component of the fluorescent cytoplasmic granules that has not been demonstrated before and share similarities with lipofuscin. Accumulation of this fibrocellular material might be related to a degenerative process at the vitreoretinal interface that is not a prerequisite for lamellar macular holes.