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Contact Lenses
| Why choose us? | | What we offer | | Lenses for Astigmatism | |
| Overnight Wear Lenses | | New Wearers Guide | | Dry eyes | |
Overnight Wear Lenses
Too much hassle to take your lenses out at night ? Then why not change to lenses that you can sleep in.
OVERNIGHT WEAR LENSES CAN BE WORN CONTINUOUSLY, WITH JUST A NIGHT OFF ONE DAY A MONTH BEFORE STARTING THE NEW PAIR.
How Are These Lenses Different?
They let through a lot more oxygen to the cornea – up to 6 times more.
Why Is This Necessary?
The cornea like all other tissues in the body requires a continuous supply of oxygen. Because it has no blood vessels of its own, it gets its supply directly from the air – oxygen from the air dissolves into the tear layer.
When the eyes are closed, no direct air transfer is possible. Instead oxygen diffuses across from the blood vessels that line the inside of the eyelids. This night time supply is much lower than the daytime one because there is less oxygen in the blood than in air. A contact lens reduces the supply further as it is a barrier through which some of the oxygen molecules don’t get through.
Overnight wear lenses incorporate Silicone which makes the lenses much more oxygen permeable.
These lenses are also good for people who don’t want to wear their lenses overnight but who have very long daily wearing times. They have also been fitted on those individuals whose corneas have shown signs of oxygen deprivation in the past, and those whose eyes just have a naturally higher oxygen requirement.