The two forms of glaucoma are described below with more detail: Glaucoma with an open angle: Open-angle glaucoma is the most common form of the disease. It starts out without any symptoms, but eventually side (peripheral) vision starts to fade, and if nothing is done, a person can go entirely blind. Closed angle glaucoma is a less common form of the condition known as angle-closure glaucoma. It takes place when the eye's drainage system becomes completely blocked, which quickly increases eye pressure.