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What Are the Treatments?

Periodic eye examinations by your ophthalmologist are essential to monitor the health of your eyes and diagnose suspected disorders. Checking the position of each eye and its movements will reveal crossed eyes or other forms of strabismus.

A Snellen eye chart employs letters of decreasing size to determine the sharpness of your vision at distance. The retinoscope projects a thin beam of light into the eye. When used with the rotating lens dial (called the phoropter) the eye doctor measures any refractive error like nearsightedness, farsightedness, astigmatism. Next, the doctor will examine the surface of each eye ysing a slit-lamp microscope. The same device is used to inspect internal eye structures located in the front portion of the eye. This is how changes in the clear cornea and lens are identified. The pressure inside the eye is measured using one of several devices. Examinations with hand-held ophthalmoscope can reveal abnormalities of the retina, the macula and the optic nerve. Some patients will need to have dilating eye drops administered in order for the doctor to complete a full examination.

If routine testing indicates that you have a refractive error, conventional treatment calls for wearing corrective glasses or contact lenses, and, in rare cases having corrective surgery. Almost 60% of the population wears corrective lenses, and that number increases markedly after the age of 65.

Conventional treatment for disorders such as nearsightedness, farsightedness and astigmatism typically relies on corrective prescription lenses. Disorders such as cataracts, glaucoma, macular degeneration, and retinal detachment require advanced medical and surgical treatments. Enormous progress in eye surgery has been made over the past few decades. Many people with eye problems previously felt to be untreatable now enjoyed improved eyesight and an improved quality of life. This applies to individuals of every age - infants to senior citizens!

To treat nearsightedness your ophthalmologist or optometrist will usually prescribe lenses to focus visual images correctly on the retina. Depending on the specifics of your eye exam, you may have a choice between wearing conventional eyeglasses and contact lenses.

As an alternative to corrective lenses, or in severe cases, surgery can be performed to treat nearsightedness. Radial keratotomy is a surgical procedure in which tiny, spoke-like incisions are made in the cornea, flattening the center and focusing images correctly on the retina. The surgery is performed one eye at a time and the success rate is good. More than three-quarters of those who have had the surgery report fully corrected or close to it. The procedure has potential complications, however: Vision may fluctuate, the cornea may become infected, and there is some risk of the corneal rupture.

Laser treatment may offer results similar to better than radial keratotomy. The laser beam removes microscopic amounts of tissue from the center of the cornea. This effectively flattens the cornea so that light rays focus correctly on the retina.

If farsightedness does not resolve itself naturally and the disorder persists into adulthood, glasses or contact lenses can be prescribed. People typically seek treatment for farsightedness when they begin to complain of eyestrain, especially at the end of the day.

For astigmatism, the accepted prescription is a lens that will correct or neutralize the effect of the uneven cornea. Again, you wil typically have a choice between glasses and contact lenses.

In cataracts, the eye's natural lens hardens and becomes cloudy, obscuring vision. Correcting the problem was once a complex procedure requiring general anesthesia and a week of hospitalization. Today, a process called "lens phacoemulsification" uses ultrasound to break up the cataract and remove the tiny lens fragments through an incision so small that it usually requires no stitches. The surgeon then inserts an artificial lens implant. Local anesthesia is used and the patient goes home from an outpatient facility within an hour or two after surgery.

There is currently no cure for age-related macular degeneration (AMD), but new treatments are sometimes able to prevent severe visual loss. Treatment for AMD may include:

• Laser therapy — to destroy abnormal blood vessels.
• Submacular surgery — to remove blood under the retina, abnormal blood vessels or scar tissue.
• Retinal translocation — surgical rotation of the damaged retinal tissue away from the macula.
• Low-vision aids — to help people with partial vision make the most of their remaining vision. These devices have special lenses or electronic systems that magnify images so it can be seen by nearby functioning retina.
• Photodynamic therapy — injection of medications that are activated by light exposure.

There is no evidence that medications are beneficial for treating this disease. Several drugs are currently being investigated experimentally. Vegetables high in carotenoids, such as spinach and collard greens, can reduce the risk of developing ARMD.

Numerous clinical research studies have demonstrated that people at risk of losing more sight due to ARMD could prevent further vision loss by taking a combination of zinc andantioxidants, including vitamins C and E beta-carotene.

Wearing sunglasses with an ultraviolet filter when outdoors and not smoking are also recommended to prevent the onset of ARMD.

Regular visits to an eye-care specialist can also help detect ARMD and other eye diseases in the early stages.

Some cases of retinal detachment can be corrected with laser surgery, which has a high rate of success. If the peeling or tearing of the retina is extensive, additional corrective surgery may be necessary.

People with the most common type of glaucoma often have to use a series of eye drops over time to keep the disease under control. In glaucoma, fluid in the eye fails to drain properly, causing pressure to build up. Laser surgery for this form of the disease, called chronic open-angle glaucoma, has been available since 1979, but ophthalmologists employ it as a later alternative to drug therapy, not as the first line of treatment.

There is no single, surefire remedy for glaucoma. Much remains to be learned about this disease. Glaucoma therapies evolve and change continously. One long-term study, however, indicates that treating people with laser surgery first works just as well, if not better, to keep glaucoma in check.

In a study sponsored by the National Eye Institute and published in the American Journal of Ophthalmology, researchers from eight medical centers around the country compared the effectiveness of the two approaches by treating one eye of each of 203 patients with laser surgery and the other with daily eye drops. After following the patients for an average of seven years, the researchers found that the laser-treated eyes had slightly lower intraocular pressure, better visual acuity and less deterioration of the optic nerve than the eyes that received drug treatment first. To keep pressure controlled, however, 56% of the laser-treated eyes and 70% of the medicated eyes required additional drugs after two years.

"No one knows precisely how the laser procedure works to lower eye pressure," says Evan Dreyer, MD, director of the Glaucoma Consultation Service at the Massachusetts Eye and Ear Infirmary, "Nor whether it can control glaucoma over the long term.

Because the disease can strike people as young as 35 and there is no cure, treatment for glaucoma may need to continue for several decades. Although some researchers express concern that the laser's effects may last only three to five years before the eyes need to be treated again, drugs become less effective over time as well," Dreyer says.

While people just diagnosed with glaucoma may be reluctant to try surgery first, there are good reasons to use it. Some patients with heart problems or asthma may not be able to take topical beta-blockers, one of the most commonly used glaucoma drugs, and drug treatment can cost upwards of $100 a month, so surgery may be cheaper in the long run. "The important thing is to preserve vision over the long term," Dreyer says. "This buys us some time."

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