Quote:
Contact lenses are medical devices and soft contacts tend to be packaged in small sterilised containers filled with fluid, which over time (hence the expiration date) can become contaminated. The biggest cause of infection, however, is overnight wear, says Professor Roger Buckley, associate director of the Vision and Eye Research Unit at Anglia Ruskin University. Sleeping with your lenses in raises the risk of corneal infection twentyfold. The cornea is starved of oxygen when lenses are in and eyelids closed, making it less effective as a barrier for keeping out germs. The overall risk is still small (3.5 per 10,000 people wearing daily soft lenses), but keratitis is painful, can make your eyes weep and causes blindness. So should contact lenses be treated with more respect?
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