The eyes have it - eye care advice

Dance Magazine, April, 1997 by Marian Korosko

What do pilots, police officers, athletes, actors, and dancers have in common? They can't wear glasses while working. Micro- and refractive surgeries can now replace the need for glasses by correcting unbalanced vision and reshaping the cornea.

A patient, who had received refractive surgery less than ten minutes earlier, emerged from the doctor's office and was ready to go home. Looking through an opthalmologist's lens, the only apparent indications that a procedure had taken place were several thin, spoke-like red marks on the surface of the cornea, indicating microscopic incisions. Eric R. Mandel, M.D., had just performed refractive surgery on his patient and corrected his eye sight so that he would not have to wear glasses. The patient wore no patch and went off with no apparent discomfort.

Radial Keratotomy (RK), Astigmatic Keratotomy (AK), and Automated Lamellar Keratoplasty (ALK), are commonly performed procedures selected by people who want to be less dependent on glasses or contact lenses for the correction or improvement of myopia (nearsightedness), hyperopia (farsightedness), and astigmatism. These conditions may appear at any age.

Radial keratotomy involves making spokelike, microscopic incisions that flatten the cornea, allowing light rays entering the eye to be focused closer to the retina instead of in front of it. The result is more normal vision in myopics. Astigmatic keratotomy involves one or two incisions on the surface of the cornea in a curved pattern. These incisions correct the shape of the cornea, which is not round but football-like in astigmatics. Automated lamellar keratoplasty also reshapes the cornea using a microsurgical instrument to remove a minuscule layer covering the cornea, thus flattening it to correct virtually any degree of nearsightedness.

HOW THE EYE WORKS

Similar to a camera, the eye has a shutter--the colored iris--to regulate the light admitted into the eye; a clear window--the cornea; and a lens, located behind the dark pupil of the cornea, that focuses light rays onto the retina in the back of the eye, which then transmits the viewed object to the brain for identification.

Myopia, an inherited condition where light rays entering the eye are focused in front of the retina instead of directly on it, causes the patient to see near objects more clearly and far objects as blurry.

Farsightedness, also an inherited condition, occurs when light rays focus behind the retina instead of directly onto it, causing the patient to see distant objects more clearly than near objects, although both are blurred.

Astigmatism is an eye condition in which the curve of the cornea is not entirely round in shape, making it difficult for the patient to clearly focus on an object and results in blurred vision.

Dance training requires developing peripheral vision to gauge your place in a floor pattern without looking directly from side to side; focusing on an object to avoid becoming dizzy during tours (which involves the inner ear); estimating the distance of your partner's preparation for a jump; and recovering your sight when you leave the spotlight on a darkened stage and walk into the wings.

At any age, if a dancer's vision is blurry at three to six or more feet from a focal point, it's time to consider wearing contact lenses, as do twenty-five million Americans. According to ophthalmologist Mandel, contact lenses should not be worn until a dancer is fifteen or sixteen years old, when handling the lenses carefully and keeping them clean can be responsibly done. "The cleaning and disinfecting process," Mandel warns, "should not be taken lightly. Be sure to remove your lenses before removing stage makeup and do not sleep with lenses in your eyes, which can be most dangerous." Disposable lenses may be the better choice for a young performer.

Between the ages of nineteen and forty-nine is the best time to consider refractive surgery, if the patient is a suitable candidate and the prescription for glasses has been stable for one year. Mandel says: "I turn down about fifty percent of the people who want the surgery, because you have to qualify for this procedure for good results. Of the people I choose, easily ninety-eight percent are happy with the results."

First introduced in North America in 1978, RK has permitted several hundred thousand patients to pass driver's license exams (90%) without glasses or contacts. Refractive surgery, however, is not covered by insurance and costs about $1500 per eye, which includes the procedure, pre- and post-op testing, and any enhancement that needs to be done within six months.

LASER SURGERY

The laser, Light Amplification by Stimulated Emission of Radiation, is a concentrated beam of light, created when an electric current passes through special gases. The Excimer laser, composed of ultraviolet waves, has a follow-up record of ten years; RK has over twenty years. The Excimer laser can sculpt or reprofile the cornea to reduce or eliminate the need for glasses or contact lenses and is more effective for higher degrees of nearsightedness; LASIK (Laser Assisted Insitu Keratomilosis), an Excimer form of surgery, can correct an even higher degree of myopia. Other types of lasers are used in manifestations of diabetes, glaucoma, retinal diseases, and post-cataract membranes. Argon and Kryton, thermal lasers, can seal leaking blood vessels caused by diabetes or seal a retinal hole before retinal detachment. Argon lasers can also lower pressure inside the eye to treat open-angle glaucoma, while YAG (Yttrium Aluminum Garnet) lasers (photodisruptive lasers) can create a new drainage system in narrow-angle glaucoma or can remove membranes after cataract surgery.