Glaucoma Is A Group Of Disorders In Which The Main Risk Factor Is High Fluid Pressure Within The Eye. All Glaucoma Disorders Are Characterized By Vision Loss, Caused By Damage To The Optic Nerve. The Optic Nerve Provides The Pathway From The Eyeball To The Brain. If A Doctor Discovers It Early And The Patient Follows Directions Carefully, The Damaging Effects Of Glaucoma Can Be Addressed. In a normally functioning eye, fluid is being formed and drained constantly. However, when an eye's drainage canals do not work well, the fluid cannot get out. The extra fluid raises the pressure inside the eye. The increased pressure can destroy sensitive nerve fibers on the back wall of the eye. Each time a nerve fiber is lost, the eye loses some ability to see. Usually, the glaucoma patient loses peripheral (side) vision first; eventually central vision can be lost. When vision is lost from glaucoma, it is irreversible and cannot be restored.