Many people use soft contact lenses for their daily vision correction needs. Sometimes, however, these may not be enough to address your vision, eye health, or comfort needs with contact lenses. Other, more specialized options exist in such cases, and one of these options is the use of scleral lenses.
What is a Scleral Lens?
A scleral lens is a large diameter, rigid contact lens that vaults over the entire front clear part of the eye, the cornea, to sit comfortably on the white part of the eye: the conjunctiva and sclera. It differs from the regular soft contact lenses you may be familiar with in that it is somewhat larger, hard, and must be filled with special fluid before being placed on the eye. Even though it is made of a rigid material, it is actually quite comfortable, owing to the fact that it does not touch the sensitive cornea and constantly hydrates the front of the eye with the tear-like fluid that it is filled with. These features are the basis of why your optometrist may recommend scleral lenses to you.
Uses of Scleral Lenses
One of the primary needs for a scleral lens, or any rigid lens, is to improve vision when the cornea becomes irregular and no longer transmits a clear image to the back of the eye. This can occur for several reasons: conditions such as keratoconus where the cornea thins and becomes pointed, after a surgery to the eye where the tissue is changed in some way that does not enable proper vision, or after severe injury to the cornea, again causing its structure to weaken and shape to change. If you have severe dry eye disease that is not solved by other treatments, your eye doctor may recommend scleral lenses as a way to protect the eyes from feeling dry and painful.
How to Use a Scleral Contact Lens
Scleral lenses are different from other contact lenses in that they completely vault over the cornea and must therefore be filled with fluid to keep them in contact with the eye. Before the lens is put onto the eye, it must be filled to almost overflowing with unpreserved saline solution. While the wearer keeps their face parallel to the ground, the lens is raised to the eye. If it is not applied properly, a bubble will form and the lens must be removed, filled with fluid, and put on again. For removal, a plunger can be used or the eyelid can be moved underneath the lens to break suction and remove it. Like any other contact lenses that are repeatedly used, scleral lenses must be cleaned regularly by rubbing and rinsing with special cleaning solution and never with tap water. They must also be stored in disinfectant solution overnight.