Massive retinal gliosis. A reactive proliferation of Muller cells
T. M. Nork, M. W. Ghobrial, G. A. Peyman and M. O. Tso
Both Muller cells and astrocytes have been implicated in the dispute over
the histogenesis of massive retinal gliosis. We studied three cases of
massive retinal gliosis by light and electron microscopy and
immunocytochemistry. Spindle fibrillary glial cells were joined by zonulae
adherentes resembling those of the external limiting membrane of the
retina. Furthermore, these cells produced a continuous basement membrane
around an extracellular space filled with fine filaments, which was highly
suggestive of vitreous cavity. In the proliferating cells, immunoperoxidase
technique disclosed the presence of carbonic anhydrase isoenzyme C,
characteristically found only in Muller cells. The glial cells in the
preretinal membrane away from the gliotic nodule showed similar
characteristics. We concluded that both the nodule of massive retinal
gliosis and the associated preretinal glial membrane resulted from the
proliferation and migration of Muller cells.
