Observation of Kolmer's crystalloid outside the retina. Presence in the corneal endothelium in various conditions.

A structure similar to Kolmer's crystalloid, an organelle found in the horizontal cells of the retina, was observed in endothelial cells of the cornea from four patients (one case of hyperparathyroidism and three cases of corneal dystrophy). Based on a morphological analysis it is concluded that the structures in the present cases are identical with the cytoplasmic structure of the horizontal cell, and that the membranous tubes probably constitute a special form of rough surfaced endoplasmic reticulum, eventually involved in transport and/or a specialized protein synthesis.