Low Water Content Contact Lenses

Since they need less moisture to remain permeable silicone hydrogel lenses can be safely worn for longer periods of time depending on the kind and brand of lens.

Low water content contact lenses.

Low water content contact lenses containing less than 40 percent water medium water content containing 50 to 60 percent water and high water content contact lenses containing more than 60 percent water. First introduced in the 1990s silicone hydrogel lenses allow even more oxygen to pass through to the cornea than regular soft contacts and they generally have low water content. High water content up to 90 hydrogel contact lenses for more sensitive eyes. Some people can wear ciba vision night and day contacts overnight for 30 days while other people will never be able to sleep in contact lenses overnight without having problems dry eye infection not enough oxygen etc.

There is significant variation in thickness and water content of hydrogel contact lenses because people will respond differently to the materials. Soft contact lenses are usually available in three categories. They tend to send more moisture to. High water content lenses are lenses with more than 50 water whereas low water content lenses have less than 50 water.

Soft contact lenses are categorized by how much water they contain. In theory under the facility of the exact same product contact lenses with higher water content are softer and the oxygen permeability is better. As a rule with conventional soft contact lenses the higher the water content the more oxygen can pass through the lens. Low water content up to 45 modern silicone hydrogel contact lenses used in contacts that are intended for continual wear.

They have almost 100 oxygen permeability. Water content is an important feature of the various plastics used to make soft contact lenses. This is important for lens comfort and healthy eyes but high water content lenses may be more fragile so are more likely to tear with frequent handling. Generally hydrogel lenses that have a low water content are thinner than soft lenses that have a high water content.

Contact lenses with a lower water content dehydrate less on the eye than do lenses with a high water content so they could be better for people with dry eyes. High water content lenses are more likely to cause dry eye than those with low water content. Water content is an important parameter of contact lenses that reveals the percentage of water in contact lenses. For those who wear soft contact lenses the water content ranges between 38 to 75 percent.

In general contact lenses are broken down into high water content and low water content lenses. For some people 38 percent water content will be just fine and for others it won t be sufficient.