Contact lenses are one of the most popular methods of correcting vision in patients with conditions like nearsightedness, farsightedness, and astigmatism. Unlike glasses, contact lenses are worn directly on the surface of the eyes, eliminating many of the inconveniences of wearing glasses. Standard contact lenses make contact with the entire surface of the eyes, and this means that they aren’t necessarily suitable for every patient, particularly those with issues with their cornea. Fortunately, that doesn’t mean that those patients can’t benefit from contact lenses. Instead, they may need to consider a type of specialty contact lens known as scleral lenses.
Scleral contact lenses are large-diameter contact lenses that have a special vaulted design, only touching down on the sclera, which is the white part of the eye. The space that is beneath and that vaults over the top of the cornea plays an important role in the suitability of these lenses for those patients who can’t wear regular varieties. They are designed this way to accommodate some corneal abnormalities and other conditions that can prevent a patient from wearing normal, full-contact contact lenses.
To make scleral lenses even more versatile, there are several sizes to choose from:
Semi scleral: the smallest variety although they are still larger than standard contacts, they rest on the line where the cornea meets the sclera.
Mini scleral: slightly larger than semi-scleral lenses, these touch down on the surface of the eye at the anterior of the sclera.
Full scleral: these have the largest diameter and also the greatest amount of clearance in terms of the vault over the cornea.
Scleral lenses are usually recommended for patients who have conditions that make regular contact lenses unsuitable. These include those who experience the following ocular problems:
Many people have corneas that are evenly-shaped domes that fit well into regular contact lenses. However, some patients have corneas that are unusually steep or have bulges, such as in a condition called keratoconus, which is characterized by the thinning and bulging of the cornea due to weakened corneal fibres. People with keratoconus can struggle to wear regular contact lenses, while scleral lenses have sufficient space beneath the vaulted section to accommodate most corneal abnormalities.
Dry eye is the name of an actual eye condition that occurs when there is a problem with the tear film that’s usually covering the surface of the eye. Contact lenses float on this tear film, but if a patient has dry eyes, it may be difficult or impossible to wear regular contacts. Scleral lenses keep tear film trapped on the surface of the eye in the fluid reservoir that is created by the gap between the cornea and the lens, enabling them to be worn by patients who have dry eye. Scleral lenses are also made from gas permeable material that allows more oxygen to reach the eyes, preventing them from drying out as quickly as they might with regular contact lenses.
Some ocular diseases affect the surface of the eyes and make it difficult for patients to wear normal contact lenses. Fortunately, scleral contacts create a barrier that protects the compromised anterior ocular surface from exposure, making it possible for those patients with ocular surface diseases to still wear contacts instead of glasses.
If you would like more information about scleral lenses and who might benefit from them, call our knowledgeable eye care team today at call 432-445-3662 for West Texas Eyecare in Pecos or Fort Stockton – they’d be delighted to assist you.