Glaucoma is a group of eye conditions that damage the optic nerve, the health of which is vital for good vision. This damage is often caused by an abnormally high pressure in eye. Symptoms of glaucoma are patchy blind spots, tunnel vision, severe headache, eye pain, nausea and vomiting, blurred vision, halos around lights, eye redness. Types of glaucoma are open-angle glaucoma, angle-closure glaucoma, normal tension in glaucoma, pigmentary glaucoma. Glaucoma treatment is done by ophthalmologists or eye surgeon.