This grant investigates the effects on the retina, optic nerve head, and optic nerve of monkey and human eyes of experimental and chronic human glaucoma. Neuro-anatomical methods of investigating retinal ganglion cells and their axons, as well as their terminations in the lateral geniculate body, are used to detect the sequence of cell death by type caused by elevated eye pressure. The aim is to develop better psychophysical tests for the early diagnosis of glaucoma. Studies of changes in structure of the optic nerve head, both clinically and histopathologically are correlated with each other in order to diagnose better the physical appearances that result from the pathologic events of glaucoma. Detailed studies of the molecular structure of the supportive tissue of the optic nerve head are performed, investigating both the cause of damage to nerve fibers and the events which occur clinically that may point towards susceptibility factors causing some persons (blacks and myopes) to suffer damage from glaucoma at a greater rate.