Glaucoma is a condition which affects the nerve in the back of the eye. It consists of millions of small fibers that course from the back of the eye to the back of the head where electrical impulses are processed into vision. There are many types of glaucoma, but the most common form has no symptoms. If glaucoma progresses, it usually causes painless loss of side vision. With severe loss of side vision a person's ability to navigate their surroundings can be difficult. A comprehensive eye exam can help detect glaucoma. The sooner glaucoma is detected the better are the chances to stabilize the nerve and prevent loss of peripheral vision.