There are several different forms of glaucoma that affect patients, the most common type being open-angle glaucoma. In open-angle glaucoma, something has gone wrong with the drainage canal through which the clear fluid that nourishes the eye is returned into the bloodstream. The aqueous clear fluid is unable to drain fast enough, causing pressure to build up within the eye. The accumulation of fluid exerts pressure on the fragile optic nerve that connects the eye with the brain. If the pressure on the optic nerve remains at a high level for too long, permanent blindness can occur. Unfortunately, the symptoms of glaucoma often go unnoticed, as patients do not experience pain or other signs of problems. However, early signs of vision loss include depletion of peripheral vision. Contact our Chicago, Illinois area practice if you suspect you are suffering from glaucoma.