Look Here: Treatments for Poor Vision

Approximately 14 million Americans over the age of 12 suffer from visual impairment, according to the National Health and Nutrition Examination Survey (NHANES). The most common forms are the refractive disorders myopia and hyperopia.

Myopia (nearsightedness) is a condition in which distant objects are out of focus. It happens when the eyeball is too long or when the outer layer of the eye, the cornea, has too much curvature. This causes the light rays to focus at a point in front of the retina instead of directly on it.

Hyperopia (farsightedness) is the opposite problem: Close objects are out of focus. Here, the problem is that the eyeball is too short or the cornea has too little curvature. The light rays therefore focus behind the retina.

Current treatments for myopia and hyperopia include several that are widely used as well as those targeted for unusual cases. In addition, some new techniques are under development:

· Corrective lenses such as contacts or glasses. Wearing glasses, by the way, will not make your vision worse, says Karla Zladnik, professor of optometry and physiological optics at the Ohio State University College of Optometry.

· Laser-related surgery such as Lasik, or PRK (photorefractive keratectomy), which changes the shape of the cornea. Over the past decade, this has grown from an expensive and exotic technique to one in wide use. Many patients are pleased with Lasik, but a small minority report problems ranging from annoying (dry eyes) to serious (compromised vision).

· Orthokeratology, a nonsurgical method using special rigid contact lenses that flatten the eye while you sleep. You can see more clearly after the lenses are removed, but the effect is temporary. The lenses must be worn each night.

· Clear lens extraction is a surgical procedure in which the lens in the eye is removed and an artificial lens is inserted.

· Phakic intraocular lens treatment involves inserting an implant into the eye while leaving the natural lens in place.

Researchers are also looking at ways of slowing the progression of myopia, especially among children:

· Bifocal glasses have been shown to slow the worsening of nearsightedness.

· Atropine is used before eye exams to dilate the pupil. This drug has also been shown to retard the progression of myopia, though it does have considerable side effects.

· An eye gel based on the ulcer drug pirenzepine is in clinical trials and looks quite promising, says Dominick Maino of the Illinois Eye Institute. According to Valley Forge Pharmaceuticals, one of the makers of the gel, its study of more than 500 children showed that myopia progressed more slowly among those using the gel than among a control group that used a placebo.

-- Ranit Mishori