Progression and regression of partial corneal involvement in the iridocorneal endothelial syndrome.

We observed three women with partial corneal involvement in the iridocorneal endothelial syndrome for more than ten years. During this time, the peripheral anterior synechiae progressed in all three, with one patient developing glaucoma. In two patients, the abnormal endothelial cells spread to cover the entire posterior corneal surface; in the third, they disappeared almost entirely. The endothelial permeability to fluorescein remained abnormally low only in the two eyes with diffusely abnormal endothelium, and increased to normal in the third eye as the abnormal endothelium disappeared. The permeability in the third eye had been abnormally low only in the superior half of the cornea, where the abnormal endothelium was located. As the abnormal endothelium regressed, it was replaced by normal endothelium with a normal cell density similar to that of the unaffected fellow eye. Thus, for more than ten years, the partial endothelial involvement associated with the iridocorneal endothelial syndrome progressed substantially in two patients and regressed dramatically in a third.