At first, open-angle glaucoma does not have any symptoms, there is no pain, and for the most part the vision stays normal. Without treatment, those with glaucoma will slowly lose their vision, usually the peripheral vision first. As glaucoma progresses, you may miss objects to the side and out of the corner of your eye.
Eventually, glaucoma can progress to the point of only “tunnel vision” or worse, with some patients with advanced glaucoma progressing to the point that no vision remains. Glaucoma typically occurs in both eyes, though the severity can be asymmetric.