The cellular composition of primary and recurrent periretinal proliferations has been widely described. The use of daunomycin, an antiproliferative antibiotic, has been recommended to reduce these proliferations. Two recurrent membranes after intraoperative application of daunomycin were examined.Methods
Two epiretinal membranes, which were removed 5 months and 20 months after vitrectomy with daunomycin, were examined by light and electron microscopy to determine the structure and cellular composition of these membranes.Results
The matrix of the membranes consisted of new collagen with fiber diameters between 20 and 22 nm. Fibrocytes and macrophages were present in both specimens. Retinal pigment epithelial cells and fibrous astrocytes were present in only one specimen.Conclusion
Retinal pigment epithelial cells, which are consistently present in primary periretinal membranes, were found in only one of the two specimens examined. Myofibroblasts, also normally present, were not found. The other cells found are typically seen in primary periretinal proliferations.