Glaucoma is an eye condition that occurs when fluid pressure in the eyes reaches harmful levels, damaging the eye’s optic nerve and causing a loss of vision. According to the Glaucoma Research Foundation, glaucoma is a leading cause of blindness in the United States, and the second leading cause of blindness worldwide.
Open-angle glaucoma is the most common form of the disease, affecting millions of people around the world. Early detection of glaucoma can help prevent the damage that leads to blindness, so it is important to know the risk factors, as well as the treatments for this progressive eye disease.
There are different kinds of glaucoma, but open-angle glaucoma is the most common kind, affecting about three million people in the United States alone. Typically, the symptoms of open-angle glaucoma occur gradually over a period of several years. For this reason, you may not notice the signs until you experience irreversible vision loss. That is why it is so important to see an eye doctor for regular visits.
Open-angle glaucoma occurs when intraocular pressure in the eye reaches a dangerous level, resulting in vision changes if left untreated. With the less common form of glaucoma, called closed-angle glaucoma, you may experience sudden eye pain, redness, nausea and a fixed, partially dilated pupil. You may also notice colored halos around lights and a sudden decrease in your field of vision. Closed-angle glaucoma is considered an emergency, and requires emergency treatment to prevent permanent eye damage.
Several different conditions can cause optic nerve damage, but studies show that the increased eye pressure associated with glaucoma is the most common cause of damage to the optic nerve. Fluid flows in and out through a chamber in the front of the eye called the anterior chamber. With glaucoma, this fluid becomes blocked or drains too slowly out of the eye, leading to increased pressure that can damage the optic nerve.
The optic nerve is important because it relays messages from the eye to the brain. Early signs of damage to the optic nerve include distorted images that may progress to vision loss or even blindness. Another cause of glaucoma is high blood pressure, which can cause increased pressure in the eyes. However, not every person with high blood pressure will develop glaucoma.
Glaucoma more commonly appears in people over the age of 60 years old. However, African Americans are at an increased risk for glaucoma and should be screened starting at 40 years of age. Glaucoma tends to run in families, so your risk for developing glaucoma increases if another family member has also been diagnosed. Mexican Americans also have a higher risk for glaucoma. Some chronic diseases, such as heart disease, diabetes and high blood pressure, also increase your risk for glaucoma.
Without treatment, people with glaucoma begin to lose their peripheral vision, leading to a condition known as tunnel vision. With time, straight-ahead vision also begins to deteriorate until eventually blindness occurs. For this reason, prevention is the most important way to avoid glaucoma.
The best way to detect glaucoma is to see an ophthalmologist for a complete eye exam every one to two years. Your eye doctor will dilate your eyes to better see the internal parts of the eye, including the optic nerve. A visual field test will be done to evaluate your field of vision, as well as a test to measure the amount of pressure in your eyes. These tests will help detect glaucoma before any symptoms develop.
If early glaucoma is detected, your doctor may order eye drops to decrease the amount of pressure in your eyes. For more severe cases of glaucoma, laser surgery is available to increase the outflow of fluid in the front of the eye where pressure can build up. Traditionally, medication has the least amount of side effects, and is the treatment of choice for most eye doctors. If you are experiencing eye pain, blurry vision or vision loss, contact an ophthalmologist as soon as possible for an examination.
- Glaucoma Research foundation: Glaucoma Facts - http://www.glaucoma.org/glaucoma/glaucoma-facts-and-stats.php
- National Eye Institute: Facts About Glaucoma - http://www.nei.nih.gov/health/glaucoma/glaucoma_facts.asp