What are Scleral Contact Lenses?
Everyone has heard of soft contact lenses. They’re the small, clear, bowl-shaped alternative to glasses that you can insert right on top of your cornea to see clearer. But there is so much more to the world of contacts than that.
Scleral lenses are large diameter rigid gas permeable lenses that completely cover the cornea (the transparent layer in front of the eye) and extend onto the sclera (the white portion).
To put into perspective of how much larger scleral lenses are compared to your traditional soft lenses, the diameter of a soft contact lens can range from 14.0 to 14.5 mm while a scleral lens can be over 20 mm!
The idea of a larger lens may seem intimidating and may have some people questioning its design and comfort. However, because of the design, it can be more comfortable for patients than soft contacts that just cover your cornea. This is true because the cornea is one of the most highly sensitive tissues in the body versus the sclera.
The conjunctiva, or the soft, clear tissue that covers the sclera, has less nerves, which reduces the sensitivity of it. Having the edges of a smaller lens touching the cornea can be very irritating, which is why some opt for a larger diameter lens. In addition to this, scleral lenses are designed to fit with little to no lens movement during blinks. Other lenses slide more over the cornea, which can disturb those who have more sensitive corneas.
Are Scleral Contact Lenses Comfortable?
The comfort of scleral lenses is usually very good especially compared to smaller diameter rigid gas permeable lenses! Another main reason why patients wear these lenses is because it helps them restore their clear vision, which has been impaired by irregularities of their cornea.
In order to have clear, non-blurry vision, one’s cornea should have a nice rounded shape that can bend incoming light towards the retina. However, certain conditions, like keratoconus and pellucid marginal corneal degeneration, can result in an irregular corneal shape. Both keratoconus and pellucid marginal corneal degeneration are diseases that cause thinning of the cornea, resulting in the front part of the eye bulging outwards.
These bulges will bend light rays in various angles that miss the retina, resulting in abnormal vision. Spectacles and soft contact lenses may help with mild cases of corneal irregularity but as the disease progresses and the cornea’s shape becomes increasingly more irregular, glasses and regular contact lenses are less effective.
Scleral lenses help mask this irregularity and provide a smooth, rounded front surface through which light can enter the eye.
Scleral Contact Lenses for Patients with Dry Eyes
Scleral contact lenses can also help with disorders that affect one’s tear film. Tears are important to the overall health of our eyes and vision. They protect and lubricate the eyes, decrease the risk of eye infections, and keep the surface of the eyes smooth and clear. However, some patients have disorders that affect the overall quality or quantity of the tears that puts them at risk for the various issues stated before.
Dry eye syndrome is a major issue, especially in older adults, that reduces the number of tears to properly lubricate and nourish the eye. Scleral contact lenses are a great solution to help alleviate the discomfort dry eyes bring. These lenses trap fluid behind the lens so when they’re placed over the cornea, the dry surface has a reservoir to consistently lubricate it.
Here at Insight Vision Center Optometry, we want you to love the way you see. That’s why we use modern technology to take topographies of our patient’s eyes. We can then properly design scleral lenses that best fit their eyes to let them see the best that they can see.
Where is Insight Vision Center Optometry?
Serving the communities of Costa Mesa, Irvine, Newport Beach, Tustin, Santa Ana, Huntington Beach, and Fountain Valley. Schedule a visit with Dr. Valerie Lam or Dr. Thanh Mai to learn more. Our optometry practice is located in Costa Mesa at 3151 Airway Ave. Suite J2, Costa Mesa, CA 92626 and we offer vision therapy, orthokeratology services, and treat keratoconus.
