Those most at risk for glaucoma include people over the age of 60, blacks over the age of 40, those with a family history of the disease and folks who have conditions like high blood pressure and diabetes. These groups should have annual eye exams starting at age 40, while everyone else should strive to have an eye exam every two to four years [source: Bain]. An instrument known as a tonometer can measure intraocular pressure, while a pachymeter measures the thickness of the central cornea, which can help an optometrist determine the intraocular pressure that's reasonable for the patient.
However, as we mentioned, some forms of glaucoma present themselves without any advanced intraocular pressure, which is why it's important to have an eye exam that includes dilation of the pupils. When the pupils are dilated, the doctor can use an ophthalmoscope to look directly through the eye to the optic nerve to check for signs of damage.
With primary open-angle glaucoma, treatment usually begins with eye drops, which work either to curtail the production of fluid in the eye or to assist the meshwork in draining more fluid. The goal is to lower intraocular pressure, thus delaying or completely preventing the onset of glaucoma, but eye drops can't cure damage that is already done. These eye drops have the potential to react adversely to other medications, so, as always, let your doctor know what other medicines you might be taking.
Sometimes pills may be used if eye drops fail to halt the damage to the optic nerve, but more often, doctors will turn to laser treatment. Lasers can be used to create tiny openings in the trabecular meshwork that allow the aqueous humor to drain. This procedure will typically help for a few years, but further treatment may be required down the road. If you go to the emergency room with a case of angle-closure glaucoma (the emergency form of glaucoma that we mentioned on the previous page), doctors may recommend this therapy.
The last resort for many doctors is a surgery known as trabeculectomy, in which a new drainage system for the eye is created. During the surgery, doctors cut a new flap into the eye so the fluid can leave the eye. Surgery is how congenital glaucoma is treated and is sometimes an option for angle-closure glaucoma as well.
Because there's no cure for glaucoma, early diagnosis and treatment are key to protecting vision. Scientists are hard at work, though, on future diagnostic and treatment tools that might include a vaccine, optic nerve regeneration and smart contact lenses that monitor the condition.
Related HowStuffWorks Articles
- "About Glaucoma." Glaucoma Foundation. (April 13, 2009)http://www.glaucomafoundation.org/about_glaucoma.htm
- Bain, Julie. "As Glaucoma Treatment Advances, Vision is Saved." New York Times. Dec. 25, 2001. (April 13, 2009)http://www.nytimes.com/2001/12/25/health/as-glaucoma-treatment-advances-vision-is-saved.html?scp=2&sq=glaucoma&st=cse
- Bakalar, Nicholas. "Care of the Eyes Demands Diligence." New York Times. May 13, 2008. (April 13, 2009)http://query.nytimes.com/gst/fullpage.html?res=9C00E3DC143BF930A25756C0A96E9C8B63
- Barras, Colin. "Smart contact lens feels the pressure of glaucoma." New Scientist. July 9, 2008. (April 13, 2009)http://www.newscientist.com/article/dn14285-smart-contact-lens-feels-the-pressure-of-glaucoma.html
- "Glaucoma." Mayo Clinic. July 17, 2008. (April 13, 2009)http://www.mayoclinic.com/health/glaucoma/DS00283
- "Glaucoma Facts and Stats." Glaucoma Research Foundation. Jan. 12, 2009. (April 13, 2009)http://www.glaucoma.org/learn/glaucoma_facts.php
- Singer, Natasha. "Love the Long Eyelashes. Who's Your Doctor?" New York Times. Jan. 14, 2009. (April 13, 2009) http://query.nytimes.com/gst/fullpage.html?res=9C06EEDB133FF937A25752C0A96F9C8B63
- Wade, Nicholas. "Study Finds Genetic Key to a Kind of Glaucoma." New York Times. Aug. 10, 2007. (April 13, 2009)http://www.nytimes.com/2007/08/10/science/10eye.html?_r=1
- "What You Should Know." National Eye Institute, National Institutes of Health. (April 13, 2009)http://www.nei.nih.gov/glaucoma/content/english/know.asp