Several eye conditions and irregularities like astigmatism, dry eye, and keratoconus make it difficult to wear contact lenses. If you have been told in the past that you are not a candidate for contact lenses due to an irregularly shaped cornea or severely dry eyes, then we recommend speaking with our eye doctors about scleral contacts.
Larger than normal gas permeable (GP) contact lenses, scleral contacts are designed to rest on the less-sensitive sclera (white of the eye) while bridging over the cornea. As a result, scleral lenses work as a functional substitute for the entire cornea, correcting vision impaired by keratoconus or other corneal irregularities. By arching over the cornea and resting on the sclera, scleral contacts create a small space between the lens and the cornea which becomes a reservoir for moisture. This fluid reservoir relieves chronically dry eyes, making it possible for a person with severely dry eyes to comfortably wear contacts.
By resting on the sclera, scleral contacts remain centered on the eye, not shifting with blinking as much as regular contact lenses. For these reasons, scleral contacts provide a lens solution for individuals with keratoconus or who have undergone a corneal transplant. The fluid reservoir between the cornea and the lens makes them a good fit for those who suffer from severe dry eye due to conditions like Stevens-Johnson syndrome, graft-versus-host disease, or Sjogren's syndrome.
Scleral contacts vary based on the required size of lens. Scleral contacts range in size from 14.5 mm to 24 mm in diameter. Even the smallest scleral contacts are designed to cover the entire cornea (The average size of a cornea is 11.8 mm.), while most conventional lenses only cover 75 to 80 percent of the cornea. The size of lens is often determined by the severity of the eye condition present in the wearer. Less severe cases of keratoconus and irregular astigmatism due to refractive surgery or corneal grafts can usually be comfortably fitted with scleral lenses on the smaller end of the spectrum. While more complex occurrences of keratoconus, ocular surface disease, and pathologically dry eyes require large scleral contacts, which provide a greater reservoir to accommodate more fluid or to bridge severe corneal bulging due to keratoconus.
Scleral Contacts Fitting with our Eye Doctors
Custom-made to match each patient's specifications, scleral contact fittings with our optometrist typically require more appointments than a regular contact lens fitting in order to determine the right lens, size, and find a perfect fit. During a fitting, our optometrist measures the eyes and performs a full scan of the corneal surface to determine the patient's exact eye shape. This allows our optometrist to order the right size and shape of scleral lenses for each patient. Scleral lenses also require additional instruction regarding proper care, insertion, and removal. During a fitting, our eye doctors will answer all of your questions about scleral contacts to ensure you enjoy a comfortable fit and clear vision.