Glaucoma
Glaucoma is the second leading cause of blindness, and since most cases of glaucoma have no pain and no symptoms, it is important to be screened for it every year. Glaucoma is an eye disease usually associated with an increase in the intraocular pressure (pressure inside the eyes), which leads to damage to the optic nerve. If untreated it can progress, causing irreversible damage which can lead to blindness.
The main types of glaucoma are open angle glaucoma and acute closed angle glaucoma. Open angle glaucoma is a chronic, usually slow progressing disease. It gradually reduces your peripheral vision until tunnel vision is all that’s left. It can be treated with eye drops or surgery. Acute closed angle glaucoma produces sudden symptoms like eye pain, headaches, halos around lights, nausea, red eyes and vision loss, which usually lasts for a few hours. Each attack causes more vision loss. It’s normally treated surgically.
Glaucoma is screened for using tonometry, visual fields, and an evaluation of your optic nerve. Tonometry is a measurement of the pressure inside the eyes. Visual field testing maps out any blind spots in your vision. Your optic nerve is best evaluated using a retinal photo or thru a dilated pupil.
For more information check http://www.glaucoma.org/