Glaucoma as a Neurological Disease

The retinal ganglion cells (RGC) and their axons that form the optic nerve are anatomically and developmentally an extension of the central nervous system (CNS). In fact, the optic nerve should not be considered a "nerve" but rather a CNS white matter "tract" containing glia of the white matter of the brain and spinal cord namely oligodendrocytes, astrocytes, and microglia, rather than Schwann cells. The optic nerve is also surrounded by meninges like other white matter tracts. It is not surprising that pathological processes that affect the optic nerve, therefore, demonstrate changes in the brain.