ontact lens helps to prevent complications.Extended Wear Contact Lens UseMany people are able to wear lenses continuously for many days with no apparent problem or complication. However, sleeping in contact lenses, while convenient, substantially increases the risk for infection and other complications. The oxygen supply to the cornea drops overnight while wearing a contact lens. This can lead to swelling of the cornea (giving blurred vision or the visualization of rainbows around lights), breakdown of the corneal surface, and ultimately infection of the cornea (ulcer). This risk is high enough that many eyecare providers discourage against the use of contact lenses on an extended wear basis. If the lenses are used this way, extreme caution should be taken, and the lenses should be removed with any sign of trouble (eye redness, pain, blurred vision, sensitivity to light, etc). In fact, it may be reasonable to consider refractive surgery as an alternative to extended wear contact lens use....