Glaucoma is a group of disorders whose common denominator is causing damage to the optic nerve. The optic nerve transmits all of the visual information from the retina to the brain.
In its initial stages, the damage usually causes blind spots in peripheral vision, the outer edges of what the eye can see. As the pressure builds and more damage occurs to the optic nerve it can lead to tunnel vision, loss of reading vision, and even blindness in extreme cases.
At least 2 million Americans have Glaucoma. Almost half of these people are visually impaired because of it. Roughly 4 percent are legally blind from the disorder.
What are the signs or symptoms of glaucoma?
Typically there are no symptoms with glaucoma. It’s an optic-nerve problem, and that’s not something that’s readily detected unless patients have been seeing their eye doctors regularly for annual exams.
Historically eye doctors convinced people that high eye pressure meant glaucoma. The reality is a lot of people have glaucoma without high eye pressure. It’s not even part of the definition of glaucoma anymore. Only 5 percent or fewer of patients have a high enough eye pressure that they’ll have pain or symptoms attributable to glaucoma.
If your eye doctor notices changes in your optic nerve from previous exams, he or she may suspect glaucoma. Symptoms may include small losses of side vision and tunnel vision.
The most important thing to do is to get an annual eye exam. Family history is a risk factor. So is diabetes. We generally start to say around age 40 your risk starts to go up by about a ½ percent a year. Glaucoma can happen at any age, but typically it takes time to develop. We’re more likely to be treating it in patients who are older than 40.
Am I likely to suffer major vision problems if I’m diagnosed with glaucoma?
Fortunately not. In the early days, glaucoma often went undetected until it was too late to preserve most of a patient’s vision. Now we can diagnose it usually long before a patient has had any loss of vision or any problems.
Most people should not go blind or lose significant vision with glaucoma. If it’s caught or diagnosed early you usually can maintain good vision just with eyedrops. Sometimes we might encourage laser or other surgery to get the eye pressure to a low enough level that the optic nerve won’t be damaged.
My parents had glaucoma. Am I more at risk?
The genetic inheritance of glaucoma is still unclear. About half of the people with glaucoma have a family history of the most common type of the disorder, known as primary open-angle glaucoma.
One type of glaucoma occurs in people who have had a history of being hit in the eye. This often is associated with athletes who suffer frequent eye trauma, such as boxers, basketball players (from elbows), wrestlers. Not only can they get a rise in pressure following the injury, but they also may develop glaucoma later on. All of these things stress the importance of regular eye exams.
How do you treat glaucoma?
Glaucoma is a disorder of the optic nerve, so treatment protects the optic nerve. Right now most of our treatments incorporate the use of eye drops to lower pressure in the eye, which puts less stress on the optic nerve and protects it.
You should have a comprehensive eye-health examination yearly or as prescribed by your doctor. Most of our emphasis besides early treatment is monitoring people who have risk factors and following them closely so they never develop any loss of vision or any visual function problems.
Treatment is first aimed at prevention through exams on a regular basis. If you develop glaucoma it does not mean it’s going to lead to blindness. We treat it with eye drops to prevent further damage and sometimes will incorporate the use of lasers and surgery to manage a particular individual’s glaucoma.
Does marijuana prevent glaucoma?
Marijuana is a reasonably effective drug at lowering eye pressure. However, it’s not as effective as other commercially available treatments. The systemic side effects of marijuana are much greater than the medicines we use to treat eye pressure. For that reason, those wanting a medical reason to treat glaucoma with marijuana don’t have as much scientific evidence to support them when other better alternatives are available.