The cellular mechanism underlying neuronal degeneration in glaucoma: parallels with Alzheimer's disease.

Evidence is presented that the characteristic pattern of neuronal degeneration associated with glaucoma is due to a combination of the persistent physical damage to axons at the level of the lamina cribrosa and the associated neuronal reaction to this kind of trauma. The class of neuronal cytoskeletal proteins known as the neurofilament triplet are crucially involved in the reaction to physical damage and the selective localization of these proteins to larger retinal ganglion cells may underlie their susceptibility to eventual degeneration. The appearance of glaucoma-like neuronal pathology in Alzheimer's disease may follow the reaction of neurofilament-containing retinal ganglion neurons to persistent damage to their axons by beta-amyloid plaque formation in subcortical visual centers.