How is 5 x more oxygen measured?
What does up to 5 x more oxygen mean?
- This means that the Dk/t of O2OPTIX is 5 times higher than
the Dk/t of the comparative traditional daily wear soft contact lens.
- This means that when your eye needs it most, the lens has the ability
to transmit up to five times more oxygen through the lens to the eye.
Will my eye always use 5 x more oxygen?
- A lens with higher Dk/t will always allow the eye to consume
more oxygen than a lens of lower Dk/t.
- Actual oxygen consumption will vary from person to person, by environment,
temperature, time of day and many other factors.
- As yet we do not have good measures of how much oxygen the cornea
actually consumes and there is debate in the scientific community about how
to measure and predict this.
- Traditional daily wear soft contact lenses (low Dk/t lenses) are associated
with signs of Corneal Oxygen Deficiency but silicone hydrogel lenses (high
Dk/t lenses) resolve many of these problems.
What is Dk/t?
- Dk/t is the ISO (International Standards Organisation)
approved measure to describe the oxygen transmissibility of contact lenses.
- Oxygen transmissibility is the rate that oxygen can flow through
the lens to the eye.
- Quoted values are always for a -3.00 D lens. The Dk/t value for lenses
of different powers or thickness will differ.
- Actual oxygen consumption will vary from person to person, by environment,
temperature, time of day and many other factors.
