If you have been told you can’t wear contact lenses due to an irregular cornea or other eye problems, you need to learn more about scleral contact lenses. These lenses are large in diameter and gas permeable, designed to cover over the entire corneal surface, resting on the sclera or “white” of the eye.
This creates a smooth optical surface while helping to correct vision problems caused by keratoconus and other irregularities of the cornea. It also creates a fluid reservoir between the cornea and the lens, providing comfort to those with severe dry eyes who couldn’t tolerate wearing regular contact lenses.
Scleral lenses have a diameter greater than or equal to that of soft contact lenses. Soft contact lenses range in diameter from 9.0-9.5mm and cover only 75-80% of the cornea while scleral lenses can range from approximately 14.5mm in diameter and up to 24mm in diameter.
Mini-scleral lenses are approximately 18mm in diameter or smaller. With the average human cornea being only approximately 11.8mm in diameter, even the mini-scleral lenses are designed to cover the entire corneal surface.
Corneo-scleral lenses, 13mm to 15mm in diameter, fall into a category in between rigid gas permeables (GP lenses) and mini-scleral lenses and are a good choice for those who require a larger than average GP lens to be comfortable.
The lens size you need will be determined by the severity of your eye condition. Milder cases of keratoconus and irregular astigmatism from refractive surgery or corneal grafts can be managed with smaller scleral lenses.
More severe and complex conditions like advanced keratoconus require larger lenses because of their ability to hold more fluid or bridge larger changes in corneal curvature. When you are examined for contact lenses, your eye care professional will determine which size scleral contact lenses will best suit the needs of your eye condition.
Scleral lenses tend to be more expensive than corneal GP lenses. A big factor that adds to the cost is that each lens must be custom-made to fit the individual wearer. This requires more expertise and sometimes more fitting time than standard soft or GP lenses.
In some cases, scleral contact lenses may cost up to three or four times more than standard contacts but when compared to the cost of soft contact lenses or hybrid lenses, the difference in cost is not as significant. This type of lens can provide the wearer with better vision and more comfort than GP or soft contact lenses, so do not let the potential costs keep you from experiencing the benefits these lenses can offer.
Since coverage for scleral lenses may vary depending on your insurance provider, it is important to consult with your eye care professional to learn more about payment and insurance coverage options. Contact Dittman Eyecare today to schedule a contact lens exam.