If there’s a type of contact lens called the gas permeable contacts, then there’s also one which is called the Silicone Hydrogel contact lens also known as super permeable lenses. This type of contact lens allows high amounts of oxygen to pass through the lens which in turn makes it the most comfortable, wearable and long lasting among its counterparts. Silicone Hydrogel contact lenses can be worn for as long as 30 days straight, without removal. The reason behind this contact lens breakthrough is the compound, silicone. Oxygen is a requirement for proper blood circulation in the eye’s cornea. Silicone allows more gas and oxygen to pass through compared to any other permeable other material out there.
Soft contact lenses are usually made out of hydrogel polymers, a soft and water containing plastic material. Hydrogel polymers are not gas permeable the eye gets oxygen through the water inside the plastic material. This small amount of water contains a minimal amount of oxygen plus it will eventually dry out in time, making oxygenation insufficient. Silicone Hydrogel contact lenses use both the water content in polymer and the gas permeability of silicone to provide adequate oxygenation to the eyes. With silicon hydrogel lenses, water content is less, which in turn, provides more comfort and less dehydration.
As mentioned, silicone hydrogel contact lenses can last up to 30 days without removal. Some manufacturers sell different variants, which include daily wear lenses, 6 to 7 night contacts and 8 to 20 days lenses. Silicone hydrogel contact lenses may not be for everyone. Prior to getting a pair, it is best to consult an eye specialist. They can thoroughly examine and evaluate the eye for any condition that might not go well with this type of contact lens. Contact lens fitting is also done to ensure eye comfort, lens durability and optimum eye health.