Abstract
Purpose: :
To investigate the ultrastructure of the internal limiting membrane (ILM) and epiretinal tissue in eyes with recurrent macular holes.
Methods: :
Pars plana vitrectomy with en–bloc removal of the ILM and epimacular tissue was performed in 14 eyes with recurrent macular holes. The specimens were processed for light and transmission electron microscopy.
Results: :
Fibrocellular proliferation at the vitreal side of the ILM was found in 12 cases. Fibrous astrocytes, fibroblasts, myofibroblasts and macrophages were observed in descending order. Mono– and multilayered cellular membranes were seen in 10 eyes. In these cases, masses of newly formed collagen were found. Native vitreous collagen fibrils were sparsely distributed at the vitreal side of the ILM in some cases only. In the remaining 2 eyes, the ILM was devoid of cells and collagen.
Conclusions: :
In recurrent macular holes, epiretinal membranes show massive proliferation of cells and newly formed collagen. This is in contrast to idiopathic macular holes which had been closed by one operation. Mechanisms for macular hole formation seem to differ in idiopathic and recurrent macular holes. Recurrent macular holes are characterized by strong tangential traction in areas of remaining ILM, which is not found in macular holes closed successfully by one operation.
Keywords: macular holes • proliferation • pathology: experimental