Glaucoma: The eye disease you don’t see coming
You could have glaucoma and not even know it.
Of the 2.7 million people in the U.S. with the condition, only about half are aware they have it. And yet glaucoma is the second leading cause of blindness in people over 65 and can be prevented with an annual eye exam.
Your vision may be generally good, and you don’t have any symptoms. But maybe reading has become a bit more difficult, or you’ve decided to get new frames for your glasses.
“Glaucoma is a disease of the optic nerve” that can happen at any age, said Jane Schweitzer, MD, an ophthalmologist who practiced at Falmouth Hospital.
Here’s what you need to know about glaucoma:
- Early treatment is more successful. If treatment fails, the glaucoma may have been too advanced when the patient was diagnosed.
- Damage from glaucoma cannot be undone. Whatever vision is left at the time of diagnosis is the starting point of treatment.
And the only way to diagnose glaucoma is to get a thorough and complete eye exam. No one likes those dilating drops that open your pupils to a frustrating experience of light shows and glare. But, Dr. Schweitzer said, “to decline an exam with dilation is not good.”
Dilation allows your ophthalmologist to visualize the optic nerve for damage, she said. And measuring the pressure in the eye, through Applanation tonometry, is another important step in the diagnosis.
The two most common types of glaucoma are open angle and closed angle, both resulting from changes in the pressure of the eye that causes damage to the optic nerve.
What keeps that pressure at a healthy level is called aqueous humor fluid (not tears), which flows through the front porous part of your eye. If the porous area becomes blocked and the fluid is unable to drain out through a small duct, then your eye pressure rises, causing open angle glaucoma.
Closed angle glaucoma happens when there a structural change in the iris blocks the angle of the drainage path of aqueous fluid.
Treatments for glaucoma include a variety of eye drops, which can help to slow progression of the disease, and laser treatment that allows the fluid to drain better by improving the poruous area of the eye.
Surgery is the last and most difficult treatment. It is a complicated and more involved procedure to build an alternate route for the drainage, and the results can be unpredictable, Dr. Schweitzer said.
Although, there are other causes of damage to the optic nerve, it is important to know the following risk factors for developing glaucoma. Dr. Schweitzer advises people to have their eyes examined more than once a year if they have more than three of these risk factors, as cited by the New England Ophthalmological Society:
- Older than 50
- History of elevated eye pressure
- African or Hispanic ancestry
- Family history of glaucoma
- Very near-sighted or far-sighted
- History of eye trauma
- Prolonged corticosteroid use
Discuss these risk factors with family members, especially if there is a family history of glaucoma and with your primary care physician at your annual exam, Dr. Schweitzer said.