February 2, 2012 at 10:16AM

Daily and monthly contact lenses remain more popular than extended wear lenses despite the fact they have now been on the market for more than ten years.
Extended wear contact lenses which are made from oxygen-permeable silicone hydrogel make up less than eight per cent of lens prescriptions worldwide.
The findings come from a study carried out by the Queensland University of Technology and published in the Optometry and Vision Science journal.
The difference between extended wear contact lenses and monthly lenses is that the former are designed to be worn constantly for the entire month, whereas monthlies must be taken out at the end of each day.
Since there have been a number of reports recently suggesting that people often sleep in their contact lenses when they shouldn't, it is surprising that extended wear lenses have not caught on.
Being oxygen-permeable means that eyes are able to breathe better when the lenses are in and should not produce the sticky substance which occurs when ordinary lenses are worn overnight.
Posted by Laura Bevan