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Key info, use of contact lenses
WHAT YOU SHOULD KNOW ABOUT DISPOSABLE CONTACT LENSES
By Dr. W. Gifford Jones
Why wouldn't anyone jump at the chance of wearing contact lenses for weeks at a time without the daily hassle of putting them in, taking them out, and cleaning them? The invention of extended-wear lenses seemed like a gift sent from Heaven. But those who jumped at the opportunity of using them for cosmetic reasons sometimes had a rude awakening. This gift carried a troublesome price tag. Some patients developed allergic reactions to the cleaning solutions. Others developed potentially dangerous infections and ulcers due to protein deposits on the lens. If they're lost during swimming several hundred dollars went down the drain. Now a new six-pack of disposable lenses may help to solve these problems. And they can even turn your brown eyes blue.
Dr. Jack Hartstein, associate professor of ophthalmology at Washington University School of Medicine says "Disposable lenses are safer, more convenient and will probably end up costing less than extended-wear lenses." He's one of several U.S. experts testing lenses for Vistakon , a subsdiary of Johnson and Johnson.
Dr. Hartstein claims the very element that makes extended-wear lenses possible also makes them dangerous. The lenses contain as much as 70 per cent water which allows a steady supply of oxygen to pass through the lens to the cornea.
By allowing the cormea to breath , the lenses remain comfortable in the eye for many weeks.
But the watery lenses also absorb protein , bacteria and chemical irritants which sets the stage for trouble. Hartstein says that even though patients are instructed to remove extended-wear lenses every two weeks and cleanse them overnight, deposits still tend to accumulate, compromise vision and eventually health. Patients often have to discard the lenses, go back to regular glasses and take antibiotics for several months to clear up the infection.
According to Dr. Hartstein the disposable lens contains only 58 per cent water. So far he's prescribed the toss-away lenses for 60 patients and reports that all but five adjusted successfully to them. Four of these patients had never worn contact lenses and had trouble putting them in as they're slightly thinner than other lenses. But he had no complaints about their fit or visual clarity. Without exception his patients are pleased .
Dr. Sheldon Wechsler of Johnson and Johnson states that disposable lenses have been tested for over four years and are currently being marketed in Florida. For the moment they are only available for nearsighted patients and those suffering from marginal astigmatism, a defect in the cornea that interferes with focus. But there will soon be disposable lenses to suit most of the 15 million North Americans who wear contact lenses.
There's one potential problem. Patients may fail to follow instructions and forget to toss away the lens. Or try to save money by using them longer. That would set the stage for a possible complication. We know that If you use a disposable razor blade too long you eventually end up nipping the skin. And if you get absent-minded or penny-pinching with disposable lenses the end result may be a serious eye infection. Since there's a little Scottish blood in many of us this occurence is a distinct possibility. To circumvent this problem some companies are considering the use of a chemical that would turn the lens a different colour following a predetermined period of time.
We don't know the cost of disposable lenses for Canadians at the moment. In the U.S. the initial fee, which includes an examination, fitting and a three-month supply of lenses in a portable six-pack, is about $175.00. Each subsequent six-pack costs $75.00. Since the lens should be changed every two weeks the cost is about $300.00 a year for disposable lenses. This compares favourably with the extended-wear lenses that cost from $300.00 to $500.00 a year.
Some other benefits accure to the toss-away lenses. You don't need to spend another $150.00 a year on cleansing solutions. If you lose your lens while travelling you're not incapacitated for the rest of the trip . All you do is reach into the six-pack for a spare. There's no need for insurance to cover lost or damaged lenses. And a study by 16 investigators showed the majority of patients had less itching, burning and blurring of vision than those using the regular extended wear lenses.
Contact lenses are a boon to those who are very near-sighted or very far-sighted. But they will not suit everyone. A few patients suffered from discomfort, blurred vision and the lens required cleaning. So think again if you simply want coloured toss -away lenses to turn your brown eyes blue.
W. Gifford-Jones M.D is the pen name of Dr. Ken Walker graduate of The Harvard Medical School. He's been a ship's surgeon, hotel physician and family doctor and later trained in surgery at McGill in Montreal, University of Rochester N.Y. and Harvard. His medical column is published by 60 Canadian newspapers and several in the U.S. He is the author of seven books. Dr. Walker has a medical practice in Toronto. His Web site is: www.mydoctor.ca/gifford-jones. He can be reached at letters@canadafreepress.com
