by Dixie Farley
Modified by FAQS.ORG
Imagine wearing your contact lenses for a few hours and then, after you
pop them out, still seeing clearly for a portion of the day. For certain
individuals with nearsightedness, that image can be reality, thanks to a
new lens the Food and Drug Administration recently cleared for marketing.
The OK rigid gas-permeable contact lens, made by ConTEX, Sherman Oaks,
Calif., is the first lens designed to correct nearsightedness by
temporarily reshaping the transparent tissue known as the cornea that
covers the iris and pupil. It is just one of many choices for the 28
million Americans who wear contact lenses.
These medical devices, sold under more than 350 brand names, offer
numerous options, including rigid-lens handling ease, soft-lens comfort,
bifocal vision, a rainbow of colors, no-fuss disposables, and even
protective help against ultraviolet radiation.
The idea behind the OK lens is not new. Since the early 1960s, some
optometrists have used conventional daily-wear rigid lenses to reshape
corneas. This procedure is called orthokeratology, or Ortho-K. FDA
considers such treatment of an individual patient to be the practice of
medicine and therefore not subject to regulation. Selling contacts not
cleared for Ortho-K to practitioners for this use is illegal marketing,
however, so the agency is helping manufacturers obtain clearances
specifically for Ortho-K.
Studies before FDA began regulating contact lenses, in 1976, show that
Ortho-K appears to be safe, says James Saviola, O.D., chief of the
vitreoretinal and extraocular devices branch at FDA's Center for Devices
and Radiological Health. "The lower your amount of nearsightedness,
the greater your probability of success with Ortho-K," he says.
Ortho-K reshaping involves the use of a series of lenses that apply
pressure to the cornea. Once the desired result is achieved, use of
daily-wear maintenance lenses is crucial to retain the reshaping. If you
wear the maintenance lenses faithfully, Saviola says, "you may only
need to wear the lenses for a portion of the day."
However, Ortho-K does not work for everyone. Some people do not
experience any significant reduction in nearsightedness. "An
individual's response is difficult to predict," Saviola says. "It
may take weeks or months to have an effect."
The most serious safety concern with any contact lens is related to
overnight use. Extended-wear (overnight) contact lenses--rigid or
soft--increase the risk of corneal ulcers, infection-caused eruptions on
the cornea that can lead to blindness. Symptoms include vision changes,
eye redness, eye discomfort or pain, and excessive tearing.
The risk of corneal ulcers for people who keep extended-wear lenses in
overnight is 10 to 15 times greater than for those who use daily-wear
lenses only while awake, says James Saviola, O.D., chief of the
vitreoretinal and extraocular devices branch at FDA's Center for Devices
and Radiological Health.
When the eyes are open, he explains, tears carry adequate oxygen to the
cornea to keep it healthy. But during sleep, the eye produces fewer tears,
causing the cornea to swell. Under the binding down of a rigid contact
lens during sleep, the flow of tears and oxygen to the cornea is further
reduced. This lack of oxygen leaves the eye vulnerable to infection.
Extended-wear rigid lenses also can cause unexpected, sometimes
undesirable, reshaping of the cornea.
Soft extended-wear lenses also bind down on the closed eye, but they
are porous and allow some tears through during sleep. Because they have so
little form, their binding has little effect on the shape of the eye.
FDA has approved extended-wear lenses for use up to seven days before
removal for cleaning. Still, there are risks with use of extended-wear
lenses, "even if it's just one night," Saviola says. Daily-wear
lenses are removed daily for cleaning and are a safer choice, provided
they aren't worn during sleep.
Another sight-threatening concern is the infection Acanthamoeba keratitis, caused by improper lens care. This difficult-to-treat parasitic
infection's symptoms are similar to those of corneal ulcers.
The use of homemade saline from salt tablets is one of the biggest
contributors to Acanthamoeba keratitis in contact lens wearers. "FDA
no longer condones the use of salt tablets, and neither should a concerned
pharmacist," writes Janet Engle, Pharm.D., in the 1996 Handbook of
Nonprescription Drugs. Engle is associate dean for academic affairs and
clinical associate professor of pharmacy practice at the University of
Illinois in Chicago.
Microorganisms may also be present in distilled water, so always use
commercial sterile saline solutions to dissolve enzyme tablets. Heat
disinfection is the only method effective against Acanthamoeba, and it
also kills organisms in and on the lens case.
Soft lenses are much more comfortable than rigid lenses, thanks to their
ability to conform to the eye and absorb and hold water. You can get used
to soft lenses within days, compared with several weeks for rigid. An
added benefit is that soft lenses aren't as likely as rigid lenses to pop
out or capture foreign material like dust underneath. Extra-thin soft
lenses are available for very sensitive people.
While the ability to hold water increases oxygen permeability of soft
lenses, it increases their fragility as well.
Rigid lenses generally give clearer vision. They can be marked to show
which lens is for which eye. They don't rip or tear, so they're easy to
Also, rigid lenses don't absorb chemicals, unlike soft lenses, which
Saviola says are like sponges. "They'll suck up any residues on your
hands--soap, lotion, whatever."
Both soft and rigid lenses offer bifocal correction. In some models,
each lens corrects for near and distance vision. In others, one lens is
for near vision, and the other is for distance. Middle-aged people who
have good distance vision but need help for reading can get a monovision
reading lens for one eye.
Soft lenses additionally come as disposable products (defined by FDA as
used once and discarded) or as planned-replacement lenses.
With planned-replacement lenses, the practitioner works out a
replacement schedule tailored to each patient's needs, says Byron Tart,
director of promotion and advertising policy at FDA's devices center. "For
patients who produce a higher level of protein in their eyes or don't take
as good care of their lenses, it might be healthier to replace the lenses
more frequently," he says.
Some practitioners prescribe disposables as planned-replacement lenses,
which are removed, disinfected and reused before being discarded. Saviola
cautions that lenses labeled "disposable" don't come with
instructions for cleaning and disinfecting, while those labeled
specifically for planned replacement do. Whatever lenses your practitioner
prescribes, be sure to ask for written instructions and follow them
Very few people wear hard lenses, but they are available for people who
have adapted to them and want them. Hard lenses are not the same as rigid
gas-permeable lenses, since they do not allow oxygen transmission through
Contacts Not for Everyone
People with inadequate tearing (dry eye syndrome) usually can't
tolerate contacts, says Donna Lochner, chief of the intraocular and
corneal implants branch of FDA's devices center. In addition, Lochner
says, "Severe nearsightedness often can't be corrected effectively
with contact lenses."
Saviola notes that certain working conditions, such as exposure to
chemical fumes, may be undesirable for contact-lens wearers. Contacts may
be ruled out by allergy to lens-care products or by corneal problems, such
as a history of viral infection of the cornea. "Extra caution,"
he says, "should be exercised with diabetics, because they're
susceptible to infection and have trouble healing."
Cosmetic use of contacts is limited in children. Adolescence is the
youngest age as a rule to consider contact lenses, says Saviola, but some
practitioners do fit 9- to 11-year-olds. "You may prescribe for a
younger child who has the motor skills and responsibility to handle
For some people who haven't been able to wear contacts and want to,
implantable lenses may be an option in the future.
Doctors are studying ring segments, "shaped like parentheses,"
Lochner says, which are implanted in the cornea. "They flatten out
the cornea, changing the shape to give the correct optical power."
Lenses that are implanted inside the eye are also being studied to correct
refractive error, she says.
Correcting vision is not the only use for contact lenses.
Some soft contacts are used as bandage lenses after photorefractive
keratectomy laser surgery for nearsightedness. The surgery removes the
outer cell layer of the cornea, creating a large abrasion on the eye. "It's
excruciatingly painful," Saviola says, "if you don't have a
protective covering on the cornea after the anesthetic wears off."
Collagen eye shields are used as bandage lenses to relieve pain from
other abrasions or sores on the cornea. They dissolve in a couple of days.
Companies that sell contact lenses compete stiffly for business,
offering discounts and premiums such as a second set free.
But a discount for the lenses might not save you money if the price
doesn't include other needed products and services, such as a thorough eye
examination, lens-care kit, and follow-up visits to make sure you're
adapting. A moderate cost for a package that has everything you need may
be the best deal.
Before you make an appointment, ask the practitioner these questions:
- Will you give me my prescription? (You may want the prescription if
you decide to go to another practitioner or order lenses from an
- What tests are included in the eye examination?
- What do you charge for the examination, lenses, evaluation, fitting,
lens-care kit, follow-up visits, and service agreements?
- What is your refund policy if I can't adapt to contact lenses?
- How many types and brands of contact lenses do you sell?
- How much do you charge for replacement lenses?
Asking questions about any new prescription treatment is always a good
idea. Like medicines, contact lenses provide benefits and pose risks. But
even with the increased risk of corneal ulcers posed by extended-wear
lenses, Saviola says this risk alone isn't enough to say the devices
aren't safe and effective if properly used.
"If people are informed," he says, "then they're making
a judgment based on available information. That's the thing we always
struggle with, conveying enough information to people and having the
practitioner convey enough information, so that the consumer can make an
Dixie Farley, who was on the staff of FDA Consumer for more than
13 years, retired from federal service in January.
Proper Care Gives Safer Wear
- Follow, and save, the directions that come with your lenses. If you
didn't get a patient information booklet about your lenses, request it
from your eye-care practitioner.
- Use only the types of lens-care enzyme cleaners and saline solutions
your practitioner okays.
- Be exact in following the directions that come with each lens-care
product. If you have questions, ask your practitioner or pharmacist.
- Wash and rinse your hands before handling lenses. Fragrance-free soap
- Clean, rinse and disinfect reusable lenses each time they're removed,
even if this is several times a day.
- Clean, rinse and disinfect again if storage lasts longer than allowed
by your disinfecting solution.
- Clean, rinse and air-dry the lens case each time you remove the
lenses. Then put in fresh solution. Replace the case every six months.
- Get your practitioner's okay before taking medicines or using topical
eye products, even those you buy without a prescription.
- Remove your lenses and call your practitioner right away if you have
vision changes, redness of the eye, eye discomfort or pain, or excessive
- Visit your practitioner every six months (more often if needed) to
catch possible problems early.
- Never use saliva to wet your lenses.
- Never use tap water, distilled water, or saline solution made at home
with salt tablets for any part of your lens care. Use only commercial
sterile saline solution.
- Never mix different brands of cleaner or solution.
- Never change your lens-care regimen or products without your
- Never let cosmetic lotions, creams or sprays touch your lenses.
- Never wear lenses when swimming or in a hot tub.
- Never wear daily-wear lenses during sleep, not even a nap.
- Never wear your lenses longer than prescribed by your eye-care
Sorting help from hype in any media--the World Wide Web, television, or
print--can pose a problem. So remember: If a claim sounds too good to be
true, it probably is.
Here are some recent examples of potential problems:
- Special effects contacts promoted on the Web with names like "Vampire"
and "Reptilian" may sound fun to try, but they could be risky,
says FDA's James Saviola, O.D. "We currently have no information
that shows pigments in these lenses are safe in the eye." While FDA
hasn't been strict about similar lenses used on a very limited basis by
entertainers, Internet advertising takes them beyond isolated theatrical
- Buying mail-order contacts with no prescription calls for caution,
says Saviola. "If your current lens has a 14-millimeter (mm)
diameter and 8.7 base curve, and the mail-order company switches to
another brand lens with a 14.0-mm diameter and 8.8 curve, it seems like
it's about the same size and shape and should fit well. Maybe it will.
But the new brand is a different material. It may leave your eyes
- A misleading print ad for Acuvue contacts was corrected last year
after an FDA warning. The ad showed a man and woman half indoors and
half outdoors on a sunny beach--no protective eyewear. "Open your
eyes to the UV around you," it stated. "And you'll be glad
Acuvue contact lenses are introducing UV protection." Writing to
Vistakon Inc., of Johnson & Johnson Vision Products Inc., FDA
warned: "The combination of this picture and the accompanying
language implies that wearing the Acuvue UV-absorbing lens outside
offers as much protection as one would naturally have indoors."
Warnings in tiny print that the lenses were not substitutes for
UV-absorbing eyewear did not "counteract the overall message"
that the lenses provided full UV protection, the agency wrote. The
company also corrected a similar TV ad.
- Misleading pricing a few years earlier prompted consumer lawsuits
against Bausch & Lomb for selling the same lens under three
different names, at three different prices.
- Charges of false claims were settled by the Federal Trade Commission
last November against J. Mason Hurt, O.D., of Bartlett, Tenn. Hurt had
touted his Precise Corneal Molding orthokeratology treatment as a
permanent cure for defective vision. A consent agreement prohibits Hurt
from making further false claims and requires reliable scientific
evidence for future claims.
At a Glance
Ophthalmologists (M.D. or D.O.) are eye surgeons
who study and treat eye diseases and can also perform the duties of
Optometrists (O.D.) examine eyes, diagnose and
treat vision problems, and prescribe eyeglasses and contact lenses. In
most states, they also can prescribe medicine.
Opticians grind and dispense eyeglasses and in
some states dispense contact lenses.