February 28, 2002
Glaucoma: A potentially serious eye disease has no obvious early symptoms
You feel perfectly fine – no headaches, no eye-strain, no clumsiness. You figure that anyone telling you that you may be losing your sight is, to put it kindly, not dealing well with reality. Unfortunately, as thousands of Americans find out every year, you could be blindingly wrong about your risk of developing glaucoma.
“Early glaucoma causes no problems that you can see,” says Dr. Philip Chen, associate professor in the School of Medicine’s Department of Ophthalmology. “It causes no symptoms until very late in the disease. Then a person may close one eye for some reason and realize that he has tunnel vision in the other eye. That may be the first clue he has that something is wrong.”
Technically speaking, glaucoma is a group of optic nerve disorders that cause a characteristic appearance of damage to the optic nerve and are most typically associated with increased pressure within the eye. Chen notes that this last fact isn’t always true.
“In the last few decades, although high eye pressure remains a major risk factor, doctors have realized there is no need to have high pressure within the eye to have glaucoma,” Chen says. “As many as 40 per cent of the people who have glaucoma may have normal pressure within the eye, and yet develop glaucoma, including the damage to the optic nerve and the visual field.”
In patients with glaucoma due to high eye pressure, the internal fluid drainage system within the eye stops working for some reason. The pressure this fluid maintains helps keep the eye round. When that fluid is unable to drain off normally, for reasons that are still being researched, glaucoma results. Incidentally, this fluid system within the eye is totally unrelated to tears.
While glaucoma can strike at any age, its incidence starts to rise once people reach their 40s. Other risk factors include:
- African-American descent. “African-Americans have glaucoma at three to four times the rate of white Americans,” Chen says.
- History of glaucoma in a close relative. “If you are told that you have glaucoma, you should urge your siblings, parents and any middle-aged children to be tested,” Chen says, “because there is a strong family link in many cases.”
- Nearsightedness.
Chen stresses that the importance of having your eyes completely examined by an ophthalmologist cannot be exaggerated. Eye pressure checks alone are not enough to detect glaucoma.
“The worse glaucoma is at the time of the initial diagnosis, the harder it is to treat,” Chen says. “If you lose part of the visual field, it can never be recovered. We can use drops to lower the pressure in the eye, and sometimes use laser or conventional surgery to halt the progression of the problem, depending on the case.”
If you are diagnosed with glaucoma, or even as being a glaucoma suspect (a person who is on the borderline of having glaucoma), it does not mean that you will eventually go blind. In contrast to the glaucoma medications of a generation ago, the eye drops used today are more convenient and usually highly effective. Chen emphasizes that complying with the treatment plan set up by your ophthalmologist is the best way to assure that your eyes will be your gateway to the rest of the world for your entire life.
For on-line information about glaucoma, visit
http://depts.washington.edu/ophthweb/iop.html
