Vision Problems

Plano Lenses and Corrective Surgeries
by Food and Drug Administration (FDA)

(Page 3 of 5)

Plano Lenses - Wearer Beware

Also known as zero-powered, decorative, or noncorrective lenses, plano lenses at one time were considered cosmetic devices. Their purpose is to temporarily change, for example, a brown-eyed person's eye color to blue, or to make a person's eyes look "weird" by portraying Halloween themes or the logos of a favorite sport team. But because these lenses carry the same infection risks to the eye as corrective contact lenses, in 2005, they became medical devices by law.

"FDA strongly believes that eye care providers are needed to fit decorative lenses," Saviola says, because of concerns about the potential for eye problems, such as pink eye (conjunctivitis) and corneal ulcers. He says that the agency also informed health care professionals of the risk of blindness and other eye injuries "if non-corrective, decorative, or cosmetic lenses are distributed without an eye care professional's involvement."

The FDA further advises people to never buy such decorative lenses at any store that doesn't ask for a valid prescription from an eye care professional. "The FDA has never cleared an over-the-counter novelty lens," says Saviola. Such sales are illegal in the United States, and for good reason: wearing contact lenses that don't fit properly is dangerous and can cause serious vision problems, abrasions, and infections.

Maria Higgins, O.D., F.A.A.O., an optometrist who practices in Pittsburgh, was part of the National Contact Lens Enforcement Petition in 2003 that strongly encouraged the FDA to enforce the existing medical device laws more effectively.

"I have had numerous experiences where a patient who was new to my office had purchased lenses at an establishment that was less than optimal," she says. Two girls, in particular, came in with flaring, red eyes, Higgins recalls. They were diagnosed with corneal ulcers as the result of overwearing colored, nonprescription contact lenses purchased from a Dollar Store. Both women had worn two-week, disposable lenses for over four months.

"I am not against patients being able to purchase lenses in places other than my office," Higgins says, "but I want my patients to be safe." Fortunately, she adds, since the new law requiring all contact lenses be dispensed by prescription only, "I've found that patients do realize the importance of being fitted by a professional." Plano lenses are as safe as any other contact lenses, Higgins adds, as long as people follow the same rules for corrective contact lenses.

Corrective Surgeries

Refractive surgery includes several surgical procedures designed to help reduce the need for glasses or contact lenses. These procedures correct refractive errors by changing the focus of the eye. Common procedures such as photorefractive keratectomy and laser in situ keratomileusis (LASIK) do this by reshaping the curve of the cornea to move the point at which light is focused onto the retina.

Various procedures with different capabilities are available. There are now four categories of refractive surgery procedures: excimer laser, implant, thermal, and other refractive procedures.

In PRK, an excimer laser capable of removing precise amounts of tissue with micron accuracy is used to reshape the central cornea - to flatten it to correct myopia, or to steepen it to correct hyperopia. PRK can also be used to correct astigmatism. The layer of cells covering the cornea, the epithelium, is removed, and the laser sculpts the cornea to correct the refractive error. A bandage contact lens is placed over the eye after the procedure to speed the epithelial healing process.

PRK gained popularity in the mid-1990s, but also was met with limitations. It worked best in patients with low-to-moderate myopia, because with higher levels, there was a risk of corneal haze. The procedure also was associated with some physical discomfort after surgery, since the cornea needed several days to heal. In some cases, it could take several months to reach the best level of vision.

By far the most popular vision correction procedure has been LASIK. Surgeons use a surgical knife, called a microkeratome, to create a hinged flap on the surface, fold it over to sculpt the underlying cornea into a new shape, and fold it back onto the cornea.

To encourage her daughter to consider LASIK, Becky Ricketts, 51, of Mt. Airy, Md., underwent the procedure for severe astigmatism in both of her eyes two years ago.

"I decided to be the guinea pig," she says. "My daughter's eyes were so bad, I just believed she would be better off having LASIK, based on results of the people I knew who'd had it done."

Ricketts's eyesight, though not as poor as her daughter's, was such that she wore glasses every day for most of her life, but not so bad that she was legally required to wear them to drive. "I've always passed my driving tests without glasses," she says. She does admit, however, that she squinted in front of the computer screen, and claims that without glasses, "everything had a fuzzy look." She was not able to wear contact lenses because the astigmatisms were so severe that "if I blinked, the contacts moved and I couldn't see." In fact, any movement of the head, Ricketts says, caused her contact lenses to move.

About the Author

www.fda.gov
FDA is A United States government body that oversees medical devices, including contact lenses, intraocular lenses, excimer lasers and eyedrops. In the US, these products must be approved by the FDA before they can be marketed.