A. Glaucoma is the name for a group of eye diseases that damage the optic nerve. The optic nerve, which carries information from the eye to the brain, is in the back of the eye.When the nerve is damaged, you can lose your vision. At first, people with glaucoma lose side (peripheral) vision.edical Reference. A. Glaucoma is the name for a group of eye diseases that damage the optic nerve. The optic nerve, which carries information from the eye to the brain, is in the back of the eye. When the nerve is damaged, you can lose your vision.