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In my opinion, the recent movement toward daily-wear lenses is not progress at all. We should be trying to figure out how to make a lens that is safe for a minimum of three months of continuous wear.”Consumers were certainly attracted to the convenience and freedom of the Permalens and other extended-wear lenses that were introduced shortly thereafter. However, as their popularity grew, so did the reports of clinical complications. By the late 1980s, it was clear that the risk of ulcerative keratitis was much greater with extended-wear lenses than with daily wear lenses; and in 1989 the FDA recommended that continuous wearing periods be decreased from 30 days to a maximum of seven days.Besides his work on extended-wear lenses, Dr. de Carle is also well known for his bifocal contact lens designs, including the de Carle bifocal. He first had the idea of placing the distance portion of the lens in the center, so that portion would be steeper and allow for better tear exchange. He then experimented with three-and five-zone lenses, including a design on which the Acuvue bifocal is based. Currently, he is wearing a new lens he invented with many zones and is negotiating with industry for potential acquisition of the technology.Undoubtedly, one of the most important developments in contact lens technology in the last 50 years is the mass production of disposable contact lenses.Michael Bay, M.D., a Danish ophthalmologist and entrepreneur, is believed to be the first to have produced a lens intended for regular disposal. His Danalens, marketed in Denmark, intrigued executives from several contact lens manufacturing companies. The material and the lenses themselves were not particularly impressive, but the manufacturing process—stabilized soft molding, in which lenses could be molded in a hydrated state—had great potential.Johnson & Johnson’s Vistakon division acquired therights to Dr. Bay’s technology in 1984 and paired it withetafilcon A, a material it had acquired three years earlier.Etafilcon A had been invented by Seymour Marco, O.D., a country optometrist who ran Frontier Contact Lens Co. of Florida. Dr. Marco was already making lenses from the new material, with limited success. Hank Green, then president of Vistakon, had the vision to put a considerable amount of Johnson & Johnson research muscle and money into refining both the material and the manufacturing process.
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