Chemical (Cold) Disinfection. There are several disinfection solutions on the market. Disinfection solutions contain chemicals such as thimerosal and chlorhexidine in sufficient concentration to kill the most common microorganisms. Since the lenses remain in the solution for long periods of time, they are kept wet and free of deposits.
The cold disinfection process is simple, and only slightly more inconvenient than storing hard contact lenses. After cleaning and rinsing the contact lenses with saline, they are placed in a special storage/ disinfection case, covered with the disinfection solution and left for at least four hours, usually overnight. Make certain that the storage case is rinsed daily with hot tap water and that it is free of any impurities before use. Read the rest of this entry »
In addition to deposits, soft lenses can carry and introduce microorganisms to the eye. This can then lead to infections, which preclude lens wear until they are cleared up. More important, infections can lead to complications if left untreated. Using a surfactant cleaner removes some organisms, but it cannot remove them all. Those that are left behind, it is feared, may find the soft, water-containing plastic a highly desirable breeding ground. Hence the need for disinfection to kill the remaining bacteria. (Lest you become unduly alarmed: The eyes have their own natural form of protection—tear immunoglobulins and the enzyme lysozyme—that combats infection up to a point. Also, soft-lens wearers who clean and disinfect their lenses as directed suffer no higher incidence of infection than either hard-lens wearers or those who wear no contact lenses at all.) Read the rest of this entry »
Surprisingly, all soft lenses are classified as drugs by the FDA because of their ability to combine chemically with medications placed in the eye. (Hard lenses do not.) The FDA must approve every new lens or lens modification as well as the solutions used in their care. Unlike hard lenses and their solutions, which have been around long enough to have been standardized, soft lenses have no established standards because the FDA insists that insufficient information still exists that would provide reasonable assurance of their safety and effectiveness. Every type of soft lens now on the market has been tested first on laboratory animals (which are “sacrificed” so their eyes can be removed and thoroughly examined), and then on a minimum of four hundred human “guinea pigs” for six months (whose eyes—thank goodness—are examined in situ). Read the rest of this entry »
“I had a lot of friends who wore hard contact lenses; in fact, I’d had a brief fling with them myself about ten years ago. But I live in a big city and couldn’t stand the pain every time a little piece of dust or soot got between my cornea and my lens. So I gave up. I don’t know how my friends continued to put up with it. Actually, some of them didn’t—gradually more and more of them began switching to the (then) new soft lenses: They seemed so happy with them. . . . They finally talked me into trying again. And, boy, am I glad they did! From the very first time I wore them they were unbelievably comfortable. I barely knew that they were there. They were so easy to wear, it was all I could to to keep myself from exceeding the hours specified in my wearing schedule. That was quite a switch from my hard-lens days, when I could hardly wait to get home to take them out. Now I wouldn’t dream of going back to wearing glasses or hard contact lenses. I feel so free and I can see much better too. I’m only sorry that I waited so long.” Read the rest of this entry »
Contact Lenses Care .
