Extended wear contact lenses
Extended wear contact lenses are generally made of flexible plastics and are available for overnight or continuous wear ranging from one to six nights or up to 30 days. They are different from other contact lenses as they allow oxygen to pass through to the cornea. Also, there are some rigid gas-permeable lenses designed and approved for overnight wear.
The duration of continuous wear depends on the type of lens and on the tolerance of your eyes for overnight wear prescribed by your eye care professional’s evaluation. The majority of extended wear lenses to be worn without removal for up to seven days have been approved by the Federal Drug Administration (FDA). However, some lenses are approved for up to 30 days of continuous wear are made from super-permeable silicone hydrogel. Silicon hydrogel contains less water than traditional hydrogel, this being an additional advantage. Result of which is that extended wear lenses are not as prone to dehydration while they’re being worn.
Extended wear contact lenses were first sold in the early 1980s but it soon became apparent that people who kept their contact lenses in over night suffered more from eye infections. Therefore, many doctors started advising their patients to remove their contacts lenses atleast while sleeping.
The situation now has changed thanks to the introduction of disposable lenses. Previously, you would wear your lenses for a week, take them out, clean them, and then re-use them. However, the cleansing process, could never be thoroughly enough to eliminate the risk of inflammation. Today, the introduction of disposable extended wear lenses that can be used for seven days or more and then replaced with a fresh pair have dramatically reduced the health concerns stemming from extended wear.
Inspite of these advances, you should always follow the advice of your eye-care professional with respect to contact lens replacement and care. While greatly reducing the risks of sleeping in contact lenses, technical advances have not removed them altogether.
Recent Comments