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Technology Sees Through the No-Contacts Excuses : There are now cheaper, safer, more comfortable versions of both hard and soft lenses.

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SPECIAL TO THE TIMES

Remember how disappointed you were when your eye doctor told you you couldn’t wear contacts?

It may be time to go back and ask again.

For years, patients with severe astigmatism, complicated prescriptions, irregular corneal surfaces or those who needed bifocals have been told they’d have to make do with glasses.

Other patients may have tried contact lenses, only to find them too uncomfortable or too much trouble.

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But thanks to a plethora of new products, most of those old reasons have become illegitimate, according to Dr. Jonathan Geller, manager of clinical research for Coastvision in Huntington Beach, one of only a handful of custom contact lens manufacturers in the world.

Longtime contact lens wearers have benefited from the new products as well, with cheaper, safer, more comfortable versions of both hard and soft lenses.

Daniel Sigband, a Huntington Beach ophthalmologist and clinical assistant professor of ophthalmology and neurology at UCI Medical School, says the starting gun for the latest technological race was fired in 1987 with the introduction of soft disposable lenses.

A Danish company first developed the molding process that made disposable lenses possible, Sigband says. “In the original manufacturing process for soft lenses, the lenses are shaped with a lathe in hard form, then hydrated to make them soft. But the molding method uses liquid plastic that is placed in a mold. It’s much less labor-intensive.”

Johnson & Johnson bought the rights to the process from the Danish company, then introduced it here. Sigband was one of seven ophthalmologists nationwide who participated in the clinical research leading to approval of the lens by the U.S. Food and Drug Administration. Sigband has participated in contact lens clinical research for the past 20 years, working with various manufacturers.

Two other companies have since joined the disposable-lens market, offering eye care practitioners more choices to give their patients the best fit possible.

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Soft lenses, whether disposable or for daily or extended wear of up to a week, have a high water content, anywhere from 38% to 55% depending on the lens, Sigband says.

One of those new lenses, for example, the SeeQuence II lens from Bausch & Lomb, is more resistant to protein deposits, a potential problem for all contact lens wearers but particularly for those with dry eyes.

Early in 1991, several companies introduced frequent replacement soft lenses, which can be worn repeatedly for one to three months and then replaced. Some of those lenses are also available with a light tint for those who would like to enhance their eye color along with correcting vision.

Also new on the market are advancements in toric soft lenses for patients with astigmatism, an irregularity in the shape of the cornea. Previously, most astigmatism patients could not get the correction they needed with soft lenses.

Some patients still need harder lenses, Sigband says. For them, gas permeable hard lenses, which allow oxygen to pass through the plastic to the eye tissue, may be the best choice.

A new gas permeable lens called Envision, for example, is “aspheric,” or not round, Sigband explains. Instead, it is designed to meet the contour of the astigmatic eye to improve vision and comfort.

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One new lens, Soft Perm, is a hybrid, with a rigid gas permeable center inside a soft lens. “These are problem-solving lenses for many people,” Sigband says.

Another new gas permeable lens material called Fluroperm 151 allows twice as much oxygen to flow through as other lenses now on the market. Sigband, who also participated in the research for that lens, says the manufacturer is now hoping for FDA approval within a year.

But all the new products have limited parameters, Sigband says, and are only available in certain powers and shapes. For patients with unusual eye problems, custom lenses may be the answer.

Coastvision was founded by Steve Downs, an optometrist who wanted to concentrate on making what were then considered “impossible” prescriptions, Geller says.

“We make soft lenses for amounts of astigmatism that are very rarely seen. The average person may be walking around with 1 or 2 diopters of astigmatism, while we make lenses for 10 diopters or more,” he says.

Because of the intensive labor necessary to make custom lenses, they cannot yet be made in disposable versions, Geller says.

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“It’s so rewarding to see the miracles that you can do,” he says. “When you have somebody with horrendous eyes and horrible looking glasses, it impacts their self-image. To be able to take people who feel trapped by their glasses and be able to free them, it’s a wonderful feeling. It’s especially true with teen-agers. It changes their whole life.

“Some patients will break down in tears. They look at themselves in the mirror from 20 feet away, and see themselves clearly without having the glasses in the way.”

But appearance isn’t the only reason for wearing contact lenses, Geller says.

“The vision really is more natural. You get more natural depth perception and image sizing than with glasses,” he says.

And some people with special eye problems can get much better vision with contact lenses than with glasses. “That enables them to do things they couldn’t before,” Geller says.

Bifocal lenses are another front in the contact lens revolution, Sigband says, and he and other experts expects that area to grow as the baby boom generation ages. “There could be potentially 40 million Americans who are candidates for bifocal lenses. Right now the success rate is only about 50%, but for that 50%, it’s 100%,” he says.

Eye care practitioners can now choose several different approaches to bifocal correction, Sigband says. The diffraction optic lens, the Echelon lens, presents the retina with two separate images simultaneously, one focused for near vision and the other for distance. The brain then must separate them out and choose one image, depending on the circumstances.

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Another type of lens has a reading portion in the center, while the outside ring corrects vision for distance. Rigid gas-permeable bifocals are also now in the design stage, he says, with aspheric lenses the most successful so far.

In other cases, doctors prescribe one lens for near vision and the other for distance, a technique called the monovision system. Former President Reagan is perhaps the best-known contact lens wearer using that system. It works quite well for many patients, Sigband says, but the disadvantage is that the patient loses the binocularity he would have if both eyes were seeing the same image.

Of the 25 million Americans who now wear contact lenses, 80% wear soft lenses, with disposable and programmed replacement lenses taking up a growing portion of that segment, Sigband says. Of the 20% who wear rigid lenses, the majority are using gas permeable, with only about 3% still wearing the original rigid lenses.

“They have excellent durability and optics, but unfortunately they do not breathe oxygen. There’s some question about the long-term safety,” Sigband says. “Most patients are being converted to gas-permeable lenses.”

No matter what type of lens you use, proper hygiene is important to successful wear, the experts agree.

“Always follow your eye care practitioner’s instructions as best you can. If you’re still having problems, go back in and find out what’s causing it. Warning signs include a change in vision, pain, or redness in the eye,” Sigband says. In the most extreme situations, contact lenses can cause corneal ulcers or infections if not used properly.

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“Hygiene and motivation are now as important to contact lens success as the condition of the eye,” says Geller, who also has a private practice in Murrietta.

Although their numbers are dramatically diminishing, some patients still simply can’t wear contact lenses. The most common problems include dry eyes, sometimes caused by medications for hypertension or allergies, or even birth control pills, Geller says. Unusually high levels of protein in the tears are a problem for some patients, because deposits build up on the lenses.

And some patients simply can’t bear the thought of placing something directly on their eye, even though the new lenses are so comfortable they can hardly be felt after a minute or so in the eye, Geller says.

Depending on the type of lens, contact lens fittings can cost from $200 to $450, Sigband says. Disposable lenses cost more initially than reusable ones, but the cost of the necessary cleaning and storage solutions makes the total cost about the same.

Other methods of vision correction have created some new contact lens users, Geller says. Patients who have had radial keratotomies, with tiny incisions in the cornea to correct nearsightedness, may need further correction “when those operations turn out less than perfect,” he says. “They also have some scar tissue, which leaves them needing less correction but with a more complex prescription.”

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