Glaucoma - Not just high eye pressure

Mon, 07/27/2009 - 8:40am
By: The Citizen

By Dr. John Henahan, OD, FAAO
Special to The Citizen

Nearly 2.2 million Americans are estimated to have glaucoma. Worldwide, nearly 9 million people are blind from glaucoma and nearly 80 million people are expected to have glaucoma a decade from now.
For years glaucoma was defined as elevated pressure within the eye that leads to vision loss. In recent research, we have learned that many people with abnormally high eye pressure never develop glaucoma. On the other hand, nearly one in three people with glaucoma NEVER have high eye pressure.

That is crucially important in understanding how to preserve your vision. Just because you have normal eye pressure does not mean you are safe from glaucoma. A simple eye pressure screening has been shown to be almost worthless in detecting glaucoma.

What’s clear is that glaucoma begins with injury to the optic nerve as it exits the back of the eye. The damage then spreads, moving from one nerve cell to adjoining nerve cells.

For now, the only treatments available for glaucoma work by lowering pressure in the eye. Even in patients with normal eye pressure and early signs of the disease, lowering pressure has been shown to significantly slow the progression of nerve damage. This is usually accomplished with eye drops. When drops aren’t enough, laser treatments and surgery can be used to allow excess fluid to flow out of the eyes.

Despite effective treatments, many people suffer some preventable loss of peripheral vision. One problem is that the disease too often goes undetected. About half of the estimated 2.2 million Americans with glaucoma are not aware that their vision is at risk because they have not been tested, surveys suggest.

Another hurdle is getting patients who know they have glaucoma to take their medicine. A 2003 study found that half of patients never filled their initial prescription for eye drops. One in four patients failed to refill their eye drops a second time, another survey found, even though eye drops need to be used every day to be effective.

While scientists search for better treatments for glaucoma, the second-leading cause of blindness, people can take action to give themselves the best chance: get a regular eye exam, and if glaucoma is diagnosed, take the treatment regimen seriously. Your sight depends on it.

Dr. John L. Henahan, OD, FAAO provides comprehensive eye exams with an emphasis on eye health. He utilizes state of the art glaucoma detection technology to ensure the health of your eyes. If you or a loved one needs an exam, contact Spectrum Eyecare at 770-487-0667 or request an appointment on the web at

login to post comments