Shortly after the November elections, two Americans who had been very much in the national limelight visited their optometrists.
President‐elect Jimmy Carter stopped in at the Brunswick, Ga., office of Dr. Carlton Hicks, who fitted him, for the first time, with one contact lens—for his right eye.
A few weeks later, TV newscaster Barbara Walters, who has worn contact lenses for years, was at the Manhattan office of Dr. Robert J. Morrison for her regular twice‐annual checkup.
Jimmy Carter and Barbara Walters have different visual problems. According to Dr. Hicks, President Carter, who has not needed corrective lenses, is beginning to have difficulty in close‐up reading and vision—a condition called presbyopiawhich afflicts most people when they reach middle age. The TV newswoman, according to Dr. Morrison. is nearsighted, or myopic, and has trouble seeing distant objects.
Carter and Walters are among several million Americans who are beneficiaries of a major—and ongoing—revolution in contact‐lens technology. They are fitted with the new, limp, waterabsorbent soft contact lenses, which are much more comfortable, but also much more costly and inconvenient, than the older hard contact lenses, made of rigid material, that have been available since the 40's.
A half‐dozen different soft lenses have been approved by the Federal Food and Drug Administration, and manufacturers are engaged in a fiercely competitive research and development race to bring out ever‐better soft, hard and in‐between lenses. The contact‐lens industry believes it can capture an ever‐in creasing share of the market of more than 100 million Americans who now wear glasses or other corrective lenses.
A startling new advance that still is classified “experimental” in the United States could measurably contribute to this goal: The development of a lens that perhaps can be safely worn for weeks, months or even years at a time without ever being removed from the eye.
About 1.5 million Americans are fitted with contact lenses each year. The principal motive, lens fitters say, is vanity. Better vision is another. For many sports activities, contact lenses are far safer than glasses, and there are football coaches who require their weak‐eyed players to wear them.
For all wearers there is the benefit, noted recently by Dr. Morrison, of coming out from behind the “vision barrier” imposed by the frames and broken visual fields of glasses. Dr. Morrison recalls one patient, a psychiatrist, who remarked that “he had lived behind glasses for so long that contacts suddenly gave him the feeling of being ‘free.’”
More and more males are wearing contact lenses, although women and girls still predominate among wearers, according to one recent survey of contact‐lens fitters. More than a third of wearers are students, this survey shows, with clerical workers and housewives the next two most common occupational groups, followed by professionals, laborers and teachers. The lenses are particularly popular with entertainers and other celebrities who live in the public eye.
Not everyone who wears glasses can switch to contact lenses, however. Even Dr. Morrison—who once predicted that contact lenses would render eyeglasses obsolete—concedes that, at least for now, there are some people who cannot use them. The strong prisms that some persons need cannot be provided in contact lenses.
Common refractive, or visual, errors that contact lenses will correct include farsightedness and astigmatism: the visual distortion in astigmatism results from irregular curves on the corneal surfaces. Nearsightedness, Barbara Walters' problem, is the commonest reason for fitting contact lenses. She has been Dr. Morrison's patient for many years. For a while she wore hard tenses, but several years ago, he switched her to a new soft lens that he himself developed. He says that with contact lenses her vision now is 20/20 in each eve.
The reading problem that bothers President Carter is not always treated with contact lenses. Many middle‐aged persons whose sight is otherwise normal simply get reading glasses. If they already arc wearing glasses, they get bifocal lenses, in which distant vision is corrected through the central portion of the lens. while an insert at the bottom provides presbyopic correction when the wearer looks down to read. In recent years, bifocal contact lenses have been developed, but are not yet perfected. The center of the lens corrects distant vision, while the outer edge is formulated for reading.
In President Carter's case, says Dr. Hicks, the preshyopia is not severe, and may only bother the President late in the day, when he is tired. Dr. Hicks therefore will leave the President's dominant, or sharper, left eye uncorrected, for distant vision. He will try to strengthen Carter's non‐dominant right eye with a soft contact lens, to make it the lead eye for reading and other close‐up work.
A distinction must he made between the large majority of contact‐lens wearers who have refractive errors that can be adequately corrected either with contact lenses or with glasses, and the medically more important minority for whom contact lenses may he the only way to treat severe, even blinding, eye disabilities.
The most severe of these problems is keratoconus, a disease in which the normally rounded cornea becomes progressively more conical in shape, ending vision in the eye. Patients whose eyes lack lenses are the other principal medical beneficiaries of contact lenses. This condition, called aphakia, often is produced deliberately, when eye surgeons remove lenses that have become clouded by cataracts, usually in old age. The thick spectacles that may be prescribed provide a narrow, tunnel vision—rudimentary sight at best. Contact lenses restore a full visual field.
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Anyone who wants to wear contact lenses must master—and practice—the tricky maneuver of inserting the lenses. The eyelids are spread wide apart with the fingertips of one hand while the opposite index finger puts the lens on the eye. Each lens is removed by putting a finger on the outside corner of the eyelids and pulling back toward the ear. A lid will catch the corner of the lens, breaking the suction, and the lens will fall out.
Many would‐be wearers simply cannot put the lenses in themselves. Some of the very best candidates—elderly patients whose cataracts have been removed, for example—are disqualified because their aged hands tremble too much to manipulate the tiny lenses.
The contact lens wearer must also undergo a “breakin period.” Hard‐lens wearers begin by wearing their lenses an hour or less a day, gradually increasing—over weeks or even months—the length of time the lenses are worn continuously each day.
For soft‐lens wearers, the break‐in period may take no more than a week or so, and some wearers go almost at once to all‐day wear. One New Jersey teen‐ager, who disliked hard lenses because “you always feel there's something under your eyelid,” says when she switched to soft lenses, “I put them in, and by the end of the day I didn't realize that they were there at all.”
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About 6 million Americans are wearing contact lenses. Half of all those who are fitted for contact lenses each year get soft lenses. First developed in Czechoslovakia in the 60's, soft lenses were brought to this country by Dr. Morrison, becoming available here in the early 70's.
If fitted properly—and this is a critical if—a soft lens hugs the corneal contours more closely than a hard lens can. This helps keep dust specks from slipping in between eye and lens, a common mishap with hard lenses that can cause excruciating pain. It also means that soft lenses, which cover a slightly larger portion of the eye surface thnn hard lenses, are less likely to pop out inopportunely.
Surprisingly, though, their softness and pliancy may not be the principal reasons for the soft lenses' comfort. Dr. G. Peter Halberg, a Manhattan eye surgeon who is president of the Contact Lens Association of Ophthalmologists, a professional group, believes that the physical trait that helps make the lenses pliant also contributes directly to their comfort: Soft lenses are hydrophilic, or water‐absorb ent. They can absorb up to half or more of their weight in body‐warmed tear fluid from the eye. “The soft sensation,” says Dr. Halberg, “comes from the fact that the material is capable of giving off water from both sides of the lens, and is warm. Something that is wet and warm is accepted by the adjacent tissue as something akin to itself.”
The key to the soft lenses' comfort is also its principal problem. The moist, warm interior of the lens is an ideal nursery for colonies of bacteria, fungi and other microorganisms that can damage the eye. As a result, soft lenses must be carefully sterilized —usually by boiling them—every day. Since eye infections can be extremely dangerous, the F.D.A. has moved with great caution in licensing lens sterilization procedures. Last year, after stubbornly resisting manufacturers' pressure for quick approval, the F.D.A. satisfied itself that a cold cleansing method—in which the lenses are soaked in solutions that kill germs and break down protein deposits from the eyes —is safe and effective—and approved it.
The soft lenses are more fragile than hard ones; they can be torn irreparably by a fingernail. Their average life span is a year to a year and a half, far less than that of hard lenses. Soft lenses also are more expensive than hard lenses. In New York City, lenses and fitting—which may require a half‐dozen visits to the ophthalmologist or optometrist—can cost $300 to $500, or more.
Some soft‐lens wearers say they see better with their contacts than they ever did before. But, by and large, soft lenses do not yield the clarity of vision obtainable with hard lenses. The result is that while lack of comfort is the principal reason why wearers abandon hard lenses, as half of them eventually do, the great majority who give up on soft ones do so because they are dissatisfied with what they can see.
For these reasons, contactlens wearers and fitters have by no means abandoned hard lenses. Many believe that people who can comfortably wear hard lenses should do so. Dr. Halberg, who is a developer of soft lenses, says; “My first preference, if a person can wear them, is hard lenses, because of their great practicality.”
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What promises to be the next major revolution in con tact‐lens technology appears to be the development of long‐wearing lenses. These lenses are not yet approved by the F.D.A. and in this country are worn on an experimental basis. The F.D.A., along with leaders in the field like Drs. Halberg and Morrison, is dismayed by the rush to what it cautiously calls extended‐wear lenses. The agency says the longterm safety of these lenses has not been proved.
An extended‐wear lens must solve some basic physiological problems that are encountered when foreign matter is introduced onto the living tissue of the eye. Like all body tissue, the cornea must take up oxygen, cast off carbon dioxide, and dissipate into the air the heat produced in its normal metabolic activities. Corneal asphyxiation will produce redness, swelling and great pain, all of which are well known to wearers of conventional contact lenses.
Several methods to overcome these problems have been incorporated into experimental lenses that are being used for extended wear. One such lens is made of a hard, cellulose‐acetate material that, its manufacturers claim, can carry off heat very well, and is permeable to both oxygen and carbon dioxide. Favorable reports on this “gas‐permeable” lens have begun to appear in the medical literature. After a dozen of his patients had worn the lenses continuously for periods of six to 15 months, Dr. George E. Garcia, a Harvard ophthalmologist, judged them to be midway in comfort between conventional hard lenses and soft lenses. He said on the basis of this limited initial experience that the lenses seemed safe, and he rated them “a significant advance in the contact‐lens field.”
This view is shared by William McGuire, a 47‐year old contact lens technician from Cleveland, Ohio, who had himself fitted with gaspermeable lenses, and began wearing them continuously on Labor Day of 1973. Except to clean some wind‐blown dust out of his eye on one or two occasions, he has not removed the lenses in the almost 1,200 days since.
If the gas‐permeable lens and similar experimental new lenses pass the rigorous tests that the F.D.A. is formulating to insure that long use does not insidiously injure the eye, then extended—or even continuous—wear may be the next contact‐lens trend. ■
https://www.nytimes.com/1977/02/20/archives/fashion-making-contact.html
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