currently i'm wearing contact lenses about 18 hours straight in a day without removing it. at first, i never thought there will be SO MANY negative effects of wearing lenses for too long until shiqah told me so.
here's some info i would like to share :)
In a nut shell: give your eyes a break. Expert say that you can get away with wearing contact lenses 12 to 14 hours a day, but that you should give your eyes a break once a week. Most experts agree that if someone wears contact lenses for too long - say for over 16 hours/day each day - their eyes could become starved of oxygen. In the long-term, this can result in the cornea losing its transparency.
If your eyes get starved of oxygen, tiny blood vessels in the eye start to shoot off and new ones develop. The most disturbing thing about blood vessels growing on the eye is that there are usually no symptoms and the eye could feel perfectly normal. An optician will be on the look out for signs of this happening, and so it is a good idea to have your eyes examined by an optician regularly.
According to a Dutch study (1), overnight use of extended-wear contact lenses is the most important risk factor for a potentially blinding form of eye infection, called "microbial keratitis".
The researchers focused on the incidence of this rare form of bacterial eye infection associated with contact lens use. In certain rare cases, microbial keratitis can result in damage to the cornea leading to partial or total blindness in the eye.
According to the researchers in this study (1), the risk of microbial keratitis was almost 20 times greater for users of extended-wear soft contact lenses and 3 times greater for users of daily-wear soft contact lenses than for people who use daily-wear hard lenses. The researchers attribute the high risk of infection of extended-wear lens users to the users’ tendency to keep the contact lenses in overnight.
HAH AMEK KAU. TRUS CUAK. NK BUKAK LENS SKANG GAK :D