Niemann-Pick disease--type C. Ocular histopathologic and electron microscopic studies.

The presence of lipid storage was demonstrated in type C Niemann-Pick disease by histopathologic and ultrastructural studies. Pleomorphic membranous inclusions, with variable proportions of light and dark granular material, were observed within the conjunctival fibrocytes, endothelial cells and pericytes, keratocytes, lens epithelium, retinal ganglion cells, retinal pigment epithelium, fibrocytes in the uveal tract, and optic nerve fibrous astrocytes. Only optic nerve and retinal ganglion cell involvement had clinical counterparts represented by optic nerve pallor and perimacular gray discoloration.