Glaucoma is an eye disease in which the normal fluid pressure inside the eyes slowly rises, leading to vision loss—or even blindness. Open-angle glaucoma is the most common form of the disease.

At first, it has no symptoms and causes no pain. Vision stays normal. As glaucoma remains untreated, people may miss objects to the side and out of the corner of their eye. Without treatment, people with glaucoma will slowly lose their peripheral vision. They seem to be looking through a tunnel. Over time, straight-ahead vision may decrease until no vision remains.

While glaucoma can strike anyone, the risk is much greater for people over 60. There is no cure for glaucoma. Vision lost from the disease cannot be restored. However, there are treatments that may save remaining vision. That is why early diagnosis is important.