What are signs and symptoms of glaucoma?

There are 2 major types of glaucoma: open-angle glaucoma and acute closed-angle (also called narrow angle) glaucoma. Open-angle glaucoma (about 90% of all glaucoma) usually has no signs or symptoms in its early stages, the first sign is usually loss of peripheral (side) vision. This is why it is so difficult because the vision loss is irreversible. Narrow angle glaucoma is very different. Symptoms of narrow angle may come suddenly and include redness, ocular pain, facial pain, headache, rainbow colored haloes around lights, nausea and vomiting which is why when this happens it is called an attack of acute angle closure and is considered a medical emergency.