A 40-year-old Chinese man only known as Liu had contact lenses he wore for a year straight surgically removed because they grew into his eyes. He said that they proved difficult to take out, and just used eye drops when they bothered him.
When his vision started to go downhill recently, he decided to put in another pair on top of the old set. Said Liu, "I put a pair of used disposal contact lenses over the other two pairs in my eyes. By then, I was wearing three pairs of lenses."
When the third pair didn't help - and his eyes suffered a bad reaction the following day - he finally decided to see a doctor.
source:
http://www.ananova.com
when i lived in ny, i left mine in for 3-5 months at a time. during a four year period i never not had contacts on -- even while sleeping. my eye doctor made me sign a waver releasing her from liablity, lol
i am better now. i take them out a night ;) it's so dry her in vegas i have to!