Histologically the nodules are made up of normal iris stroma that has been pinched off at the base by an abnormal corneal endothelial membrane that is spreading over the iris surface. These patients also have peripheral anterior synechiae and angle closure. This should not be considered a variant of ICE syndrome, but can be confused with the Cogan-Reese Syndrome. Studies have shown that the ICE syndromes represent a spectrum of disease that are linked by a common corneal endothelial abnormality. On slit-lamp examination there is a fine hammered silver appearance of the corneal endothelium and this is a consistent feature found among all of the variants of ICE syndrome.
Specular microscopy provides additional information on the endothelial changes.
These changes include endothelial cell pleiomorphism, dark areas within cells, and loss of hexagonal margins. These findings when present are essentially pathognomonic for the disease. Characteristically, the endothelium of the unaffected eye is normal. The abnormal corneal endothelial cells in ICE syndrome have apparently lost their contact inhibition and thus are capable of migration. A membrane of endothelial cells may grow over the angle and onto the iris surface to form peripheral anterior synechiae and cause glaucoma.