One of the biggest complaints for contact lense wearers over the years is the fact that you cannot sleep with them in your eyes. For some people, especially those who love the great outdoors and camping, this is a big inconvenience.
It turns out that a study on extended wear lenses (published in the New England Journal of Medicine in 1989) discovered that the risk of corneal ulcers was 5 times greater with extended wear contacts than regular contacts that were cleaned and disinfected every day. Of course, the actual rate of infection was still only 0.2 percent, but the damage was done.
The makers of these lenses now started referring to them as "flexible" wear lenses, and recommended they not be worn for a maximum of 7 days at a time. They also recommend that patients who are prone to dry eyes, have a high level of protein in their tears, or who work in dirty and dusty environments should clean and disinfect the lenses daily.
So imagine the excitement in 1981 when, for the first time, contact lenses were introduced that could be worn for several days and even overnight! They were known as "extended wear" contacts and it was claimed they could be worn for up to 30 days without cleaning or disinfecting. Too good to be true? Yep.
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Contact Lenses: Soft Extended Wear