Imagine going to bed with poor vision and waking up with perfect vision. That's the idea behind a new therapy that uses special contact lenses.

Craig Cousins has worn contacts or glasses since he was 9 years old. His vision was so bad that he couldn't see the eye chart in the doctor's office, he said.

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But now he can read even the smallest letters and he's not wearing any corrective lenses.

Last night, Cousins wore a new pair of contact lenses recently approved by the Food and Drug Administration.

"It gently reshapes the cornea to make it flatter and that changes the way light enters your eye and you become less nearsighted during the day," said Dr. Sandra Bozich.

It's called corneal refractive therapy or CRT.

After just two nights of wearing the lenses, Cousins said his vision has improved at least 75 percent.

"It's startling," he said.

His eyesight is expected to continually improve as he continues to wear the hard contacts overnight.

But doctors warn that CRT is not for everyone. It won't help those who are farsighted or who have too much astigmatism.

Eye surgeon Dr. Gary Kawesch says CRT is not risk-free.

"Any of those contact lens type procedures do have risks of permanent vision problems like infection," Kawesch said.

He says those risks are no greater than patients who wear daily contacts.

Cousins says he has experienced no problems and is only focusing on enjoying days without contacts.

The overnight contacts seem to work for most people. The lens manufacturer reports that 70 percent of patients achieve 20/20 vision or better after wearing them.