Glaucoma is a group of diseases that damage the optic nerve, the part of the eye that carries the images we see to the brain. It is a stealthy disorder, usually causing no noticeable symptoms until there is a loss of peripheral vision – and, sadly, this loss is permanent. Left untreated, glaucoma can lead to blindness; it is the second leading cause of blindness in the US. Because it is typically symptomless at first, about half of Americans with glaucoma don’t even know they have it.
Here’s a basic overview of glaucoma. Healthy eyes continually produce and circulate a clear fluid called aqueous, which provides nutrients to and removes waste from parts of the eye and then drains out through a microscopic drainage channel or “angle.” With the most common form, open-angle glaucoma, the aqueous reaches the drainage angle but doesn’t flow adequately through it, creating pressure against the optic nerve at the back of the eye and damaging the nerve fibers. “Once the nerve fibers are compromised, peripheral vision begins to fail,” says Lake Eye ophthalmologist Dr. Vinay Gutti, “until eventually the patient is left with tunnel vision.” Open-angle glaucoma affects roughly 2.2 million Americans, especially those over 40, when the risk of glaucoma increases.
In narrow angle glaucoma, the drainage channel may be blocked and/or the aqueous fluid can’t reach it and remains in the eye, creating pressure on the optic nerve. Unlike the open-angle varieties, narrow angle glaucoma often produces sudden symptoms, including eye pain, redness, light halos, headache, vision loss, nausea and/or vomiting that may go away after a few hours and recur later, or continue uninterrupted. “These symptoms should be treated as an emergency,” says Dr. Gutti. “The longer you wait, the more vision you stand to lose.”
Now the good news: When caught in its early stages, proper treatment can prevent vision loss. So it’s important to have regular ophthalmological exams, even if your eyes feel fine.
“People should make sure to have at least one comprehensive eye exam by age 40 and every few years after that,” suggests Dr. Gutti. “And those in higher-risk groups should start at 35 and retest more frequently.” Elevated risk groups include seniors, diabetics, relatives of people with glaucoma, people with very high or very low blood pressure, people who are nearsighted, and people of African, Latino and Asian descent. “If you notice sudden changes to your vision, you should see an ophthalmologist as soon as possible, regardless of your age or risk,” says Dr. Gutti. “Testing for glaucoma is painless and quick, so there’s no reason to put it off.”
People diagnosed with glaucoma are usually prescribed specialized eye drops that reduce eye pressure and help prevent or arrest damage to the optic nerve, preserving sight. Medication may be prescribed. Less commonly, surgery may be needed.
“Most vision loss due to glaucoma can be prevented,” says Dr. Gutti. “The important thing is to catch it as early as possible.”
If you’re 40 or older and/or have higher risk factors for glaucoma and haven’t had a comprehensive eye exam in the past couple of years, it’s time to call the caring professionals at Lake Eye and get started on the path to healthier vision.