Glaucoma is actually a group of eye diseases that lead to damage of the optic nerve (the bundle of nerve fibers that carries information from the eye to the brain), which can then lead to vision loss and the possibility of blindness. It’s often associated with a buildup of pressure in the eye, but glaucoma can occur with normal or even below-normal eye pressure. Normally, this fluid, called aqueous humor, flows out of the eye through a mesh like channel. If this channel becomes blocked, fluid builds up, causing glaucoma.
There are two main forms of glaucoma: open-angle (which is the most common form and affects approximately 95% of individuals) and closed-angle.
Open angle glaucoma, by far the most common form, has no symptoms at first. At some point, side vision (peripheral vision) is lost and without treatment, total blindness will occur.
Closed-angle glaucoma (acute glaucoma) results from a sudden, complete blocking of the fluid flowing out of the eye. Symptoms may include severe pain, nausea, vomiting, blurred vision, and seeing a rainbow halo around lights. Closed-angle glaucoma is a medical emergency and must be treated immediately or blindness could result rapidly.
Currently, there is no “cure” for glaucoma; however, early diagnosis and treatment can control glaucoma before vision loss or blindness occurs.
There are several tests that can help your eye care professional detect glaucoma; these include a visual acuity test, visual field test, dilated eye exam, tonometry (which measures this pressure inside of the eye), and pachymetry (which uses ultrasonic waves to help determine cornea thickness). Individuals at high risk for glaucoma should have a dilated pupil eye examination and a visual field test, annually.
Early treatment for open-angle glaucoma will usually begin with medications (pills, ointments, or eye drops, for example) that either help the eye to drain fluid more effectively or cause it to produce less fluid. Several forms of laser surgery can also help fluid drain from the eye. Incisional surgery to create a new opening for fluid to drain is usually performed after the other treatment options have failed.