Glaucoma often has no symptoms. Glaucoma is an eye disease that involves damage to the optic nerve. This nerve sends visual signals to the brain, where they are processed into what you 'see'.Glaucoma develops slowly over time. Many people will go years before noticing any symptoms. Often they don't know they have glaucoma until they lose some of their eyesight. Loss of vision from glaucoma is not reversible.more...See more text