These contact lenses are much more permeable than traditional soft contact lenses, providing more comfort to the eye as oxygen is admitted. This provides relief for the cornea and the eye in general, enabling longer usage. Some hydrogel contacts can be worn without extraction for up to a month.
How do Hydrogel lenses work?
The polymers in the contact lenses permit the access of water to the eye. The water carries oxygen with it thus enabling the eye to breathe despite the presence of the lens. The amount of oxygen supplied to the eye is restricted by how much water reaches the eye. The silicone admits oxygen both through water reaching the eye as well as via admitted air.
The advantages of silicone hydrogel
The main advantage of these lenses is that they can be worn for up to thirty days. Because the lenses can retain seven times more oxygen than standardised contact lenses, the user can keep the lenses on for longer periods of time and reduce the risk of eye infection or other ailments. Since the lenses can absorb more water than other contact lenses, they are less likely to dehydrate and thus irritate the eye. Some patients considering surgery through LASIK treatment may find the silicone hydrogel lenses a more favourable alternative.
What else should you be aware of?
Users who prefer to sleep with their lenses on will prefer this type of lens. It is important to ensure that the lenses really are thirty day lenses, as not all silicone hydrogel lenses are; there are also weekly and daily lens versions. Silicone hydrogel lenses are not available from all manufacturers and may require the administration of a special order. The potential user should also consult an eye care professional with regard to any requirement for overnight lenses or Extended Wear lenses, in order to ensure that the lens really is appropriate or suitable.