WHAT IS GLAUCOMA?
Glaucoma is a disease caused by elevated eye pressure which results in damage to the optic nerve inside the eye. The optic nerve is a bundle of nerve fibers which makes vision possible. If the optic nerve sustains damage from elevated eye pressure, permanent vision loss and blindness may occur. In the most common form of glaucoma, vision loss is gradual and it may take many years for damage to become evident.
HOW COMMON IS GLAUCOMA?
According to the World Health Organization, glaucoma is the second leading cause of blindness in the world. It is estimated that over 2.2 million Americans have glaucoma, but only half of those know they have it. 1 A comprehensive eye examination can detect whether an individual is at risk for developing glaucoma.
WHAT ARE THE SYMPTOMS OF GLAUCOMA?
Most types of glaucoma do not cause any symptoms until after irreversible vision loss has occurred. As the optic nerve becomes more damaged in the early stages, blank spots begin to appear in your field of vision, but they typically go unnoticed until the optic nerve is significantly damaged and these spots become large areas of permanent vision loss. A less common type of glaucoma is a rapid onset attack where the drainage area of the eye closes and eye pressure builds rapidly. Symptoms may include sudden blurred vision, severe eye pain, headache, rainbow-colored halos around lights, and nausea and vomiting. This is a true eye emergency that could result in blindness if not treated quickly. 2 To proactively monitor for problems, routine eye examinations every 1 to 2 years are recommended — in addition to prescribing glasses or contacts to improve vision, your eye doctor will assess the health of the eye and look for risk factors for eye diseases such as glaucoma.
WHAT ARE THE RISK FACTORS FOR GLAUCOMA?
A risk factor is something that doesn’t always lead to a condition, but increases the risk of having that condition. Risk factors for developing glaucoma include age, race, family history, steroid use, and eye injury. Some health conditions such as high blood pressure, high cholesterol, and type 2 diabetes may also be associated with an increased risk of glaucoma.3
WHO WILL DEVELOP GLAUCOMA?
Glaucoma is more prevalent in patients age 60 and older, but it may occur earlier in life and even in children. African American, Asian and Hispanic persons are more likely to develop glaucoma. If there is an immediate family member who has glaucoma, the risk of developing glaucoma increases 4 to 9 times.3 Steroid use may increase eye pressure and lead to glaucoma. Steroids may be prescribed in the form of tablets, creams, gels, eye drops, nasal sprays, or injections, and are commonly used to treat conditions in the body that cause pain and inflammation. During ocular trauma, the area of the eye that allows fluid to drain and maintains normal eye pressure may become damaged and cause eye pressure to become elevated, leading to glaucoma. The mechanisms by which eye pressure or optic nerve health are affected by high blood pressure, high cholesterol and diabetes are not fully understood at this time.
HOW IS GLAUCOMA DIAGNOSED?
Most often, glaucoma is detected during a routine eye examination. Additional testing for glaucoma may be ordered due to elevated eye pressure in one or both eyes, positive family history for glaucoma, and/or based on the appearance of the optic nerve inside the eye. Any of these clinical signs observed during a routine eye exam may result in another more detailed examination called a glaucoma evaluation.
WHAT ADDITIONAL TESTING IS PERFORMED IN A GLAUCOMA EVALUATION?
Although eye pressure has already been checked during routine testing, it will be checked again, as eye pressure may fluctuate throughout the day. A procedure called gonioscopy will be performed with a special lens that allows your eye doctor to evaluate the drainage area of the eye. Corneal thickness will be measured, as thin corneas are associated with increased risk of glaucoma. Photographs of the inside of the eye may be taken to record the appearance of the optic nerve and to aid in monitoring for change over time. Visual Field testing will be performed. This maps the sensitivity of the peripheral vision, which is likely to be affected first in glaucoma. A scan of the optic nerve, called Optical Coherence Tomography, is quick and painless and results in an image that allows your eye doctor to determine if there are signs of damage on the optic nerve that could be caused by glaucoma. Your eye doctor will evaluate the results of theses tests and may request frequent retesting to determine the presence of glaucoma and whether treatment is necessary.
WHAT IS THE TREATMENT FOR GLAUCOMA?
Treatment for glaucoma in the United States is most often the prescription of eye drops which are used 1 to 2 times daily to lower eye pressure, although a minimally invasive laser procedure is also becoming more common. Depending on the type of glaucoma and stage (mild, moderate, advanced), eye surgery may be the best treatment option to lower eye pressure. Your eye doctor will work with you to determine your next steps after glaucoma is diagnosed. Treatment for glaucoma is considered to be long-term. Once a patient begins treatment to lower eye pressure, this treatment must be maintained to control eye pressure, thereby slowing the progression of glaucoma and reducing the risk of vision loss.
IS THERE A CURE FOR GLAUCOMA?
At this time, there is no cure for glaucoma. The goal of treating glaucoma is to slow the progression of the disease that results in vision loss if left untreated and unmonitored. Therefore, early detection and treatment is the best defense against irreversible vision loss.
IS GLAUCOMA PREVENTABLE?
It is not completely understood why glaucoma develops, and there is no recommended vitamin or diet that will reduce the risk of glaucoma. However, not smoking and maintaining a healthy diet with antioxidants, fruits and vegetables, and 30 minutes of exercise 5 days a week is associated with a reduced risk of developing high blood pressure, high cholesterol, and type 2 diabetes.4 These conditions may all contribute to an increased risk of developing glaucoma. The best defense against glaucoma is early detection, staying physically healthy, and annual eye examinations.
(1) The Eye Disease Prevalence Research Group, Arch Ophthalmology. 2004; Prevent Blindness America; (2) American Academy of Ophthalmology (2012). Glaucoma, A Closer Look. San Fransico, CA; (3) Are You at Risk For Glaucoma? Glaucoma Research Foundation. http://www.glaucoma.org. Accessed Jan. 14, 2015; (4) Strategies to Prevent Heart Disease. Mayo Clinic. http://www.mayoclinic.org. Accessed Jan.14, 2015