Sondheimer On Sight: The Dangers Of Glaucoma
BY DR. STUART SONDHEIMER, MD Special Columnist
Glaucoma is a generally irreversible disease that injures the optic nerve and retinal ganglion cells that bring vision from the eye to the brain. Over a million Americans are diagnosed as having Glaucoma, and another million Americans are unaware that they have the condition. It is estimated that nearly 120,000 U.S. citizens are legally blind in both eyes resulting from glaucoma and about 1.5 million Americans have some loss of peripheral vision from glaucoma. As we age, we are at increased risk for developing glaucoma. People that have relatives with glaucoma are also at increased risk of developing the disease, but the genetic mechanism of inheriting glaucoma is poorly understood. Other risk factors include diabetes, African-American heritage, hypertension, and myopia.
There are over 40 different types of glaucoma but most of them are either Open Angle Glaucoma or Narrow Angle Glaucoma. The eye continuously manufactures fluid that drains out of the eye through a drainage meshwork and channel. The eye has pressure like a tire has pressure. With glaucoma, the pressure in the eyes is elevated.
In Open Angle Glaucoma, the access to the drainage meshwork is normal. Generally, with advancing age, fluid drainage becomes slowed and the pressure in the eye rises. Initially the patient is unaware that anything is wrong. However, the elevated pressure in the eye can gradually injure the optic nerve and retinal ganglion cells.
In medically underserved areas, many people with glaucoma may not be aware that they have the disease until they can’t see well because the elevated eye pressure has damaged their optic nerves and retinas. By the time they become aware there is a problem, it may be too late.
An eye physician detects the elevated eye pressure of open angle glaucoma at an early stage before the optic nerve is injured and then treats the condition to preserve the patient’s vision. In the United States, most patients with glaucoma enjoy excellent vision for their entire lives, but some have severe vision loss and blindness. The eye physician can detect loss of vision, elevated eye pressure, and injury to the optic nerve and retina upon examination. A visual field is utilized in patients with glaucoma. If the patient is losing or is at risk of losing the ability to see clearly or sense light on the test, then the eye pressure must be lowered. Conditions that mimic glaucoma such as brain tumors, interrupted blood flow to the eye or brain, and congenital abnormalities must be excluded. An OCT (Ocular Coherence Tomography) test may detect injury to the retina and optic nerve at an earlier stage than when the visual field test becomes abnormal.
Using eye drops that either reduce the production of fluid in the eye or increase the flow of fluid out of the eye effectively treats most patients with Open Angle Glaucoma. However, if the patient doesn’t take the eye drops as recommended or if the medications don’t work well, continued elevated eye pressure and damage to the optic nerve and retina may require laser or conventional surgery to lower the eye pressure and stop the progression of glaucoma and vision loss. These procedures may increase the flow of fluid out of the eye. Other surgical treatments reduce the production of fluid in the eye. Patients must be monitored carefully to make sure that the treatments are working.
In Narrow Angle Glaucoma, the fluid in the eye may be blocked from reaching the drainage meshwork. This is more common in shorter, farsighted eyes than in eyes that are nearsighted. With age the lens grows thicker and eventually fluid can’t easily escape the eye. Some patients have acute attacks where the vision drops, the eye becomes red and inflamed, and the pressure in the eye increases. In most cases of Narrow Angle Glaucoma, the attack of high pressure can be broken with medications; surgeries are rarely required to break the acute attacks. After the acute attack is broken, a laser may be used to make a hole in the colored iris allowing fluid to drain easily out of the eye. In other cases, surgeries to allow fluid to leave the eye or to replace the lens are necessary.
Dr. Stuart Sondheimer, MD is an ophthalmologist and eye surgeon with offices located in Park Ridge, Deerfield and Skokie. The advice contained in this column is for informational purposes only. Readers should consult with a physician to evaluate any illness or medical condition. Dr. Sondheimer accepts new patients. Call (847) 677-2794 or visit his web site at: www.drsondheimer.com.