Scleral Contact Lenses
Scleral contact lenses are focused contact lenses that sit on the sclera and provide coverage over the entire corneal surface. Unlike conventional contact lenses, which sit right on the cornea, this lens vaults above the cornea with a fluid-filled reservoir between the lens and the cornea. Therefore, this has numerous benefits for individuals with complicated corneal conditions, dry eyes, or other specific eye health needs.
What are Scleral Lenses?
Scleral lenses are larger than a traditional soft or RGP lens, usually 14 to over 20 millimeters in diameter. They primarily provide a smooth, optically clear surface over the eye, which can be helpful for patients with irregular corneas. The vaulting design creates space between the lens and the cornea that fills with tears or saline solution. This creates a liquid cushion, which maintains comfort and gives relief to those suffering from conditions that cause extreme dryness or discomfort.
Because the lenses rest on the sclera, they are much more stable compared to traditional lenses, which decreases the chance of the lenses shifting out of position. The stability enhances great visual acuity since the lens remains aligned over the pupil.
Who Can Benefit from Scleral Lenses?
Often, these patients are prescribed scleral lenses that have irregularly shaped corneas, or where the eyes happen to be severely dry or have conditions such as those that follow. These include keratoconus, a condition in which the cornea becomes thin and more enlarged in the shape of a cone under which distorted vision is witnessed, or sulfite sensitivity, contact lens complications, or refractive issues.
Post-operative corneas: After post-LASIK or corneal transplant, the surface of the cornea gets irregular. A scleral lens can help see again clearly.
Dry eye syndrome: People with very dry eyes find the protective benefit in wearing scleral lenses, which act as a shield to protect against evaporation and ensure hydration of the cornea constantly.
Irregular corneal scarring from trauma, infections, or surgeries creates irregularities. Scleral lenses cover the cornea and provide a more uniform refractive surface.
Diseases of the ocular surface: In diseases where the ocular surface is damaged, such as Stevens-Johnson Syndrome or Sjögren’s Syndrome, scleral lenses provide protection and retention of moisture.
Astigmatism: Toric soft lenses are available but, for severe or irregular astigmatism, scleral lenses might be more personalized and comfortable.
How do Scleral Lenses Work?
Because Scleral lenses are fitted to individual patients and require an extraordinary amount of fitting procedures before they can comfortably fit, through different stages of sizing, an eye care professional measures the curvature and size of a patient’s cornea and sclera using advanced imaging, such as a corneal topographer. This will create the finest map of how the eye surface is made and design the lenses accordingly.
Once their design is finalized, the lenses are produced using gas-permeable material from which oxygen freely passes through the lens and diffuses directly to the cornea. This should be carried out because oxygen is required for cellular metabolism and may prevent some complications such as corneal swelling or infection.
As the patient inserts the scleral lens, they fill it with a saline solution to create the fluid reservoir that protects and hydrates the cornea. Then, the lens rests gently against the sclera. Because it vaults from the cornea, there is no contact at all between the lens and the cornea in case the patient’s cornea is sensitive or damaged.
The benefits of scleral lenses
Scleral lenses offer several important advantages over regular contact lenses:
It is much more comfortable for the majority of patients than any other type of lens, especially for patients with sensitive or dry eyes. The fluid reservoir under the lens constantly hydrates it and eliminates friction between the cornea and the lens.
Better quality of vision in patients with irregular corneas compared to glasses or traditional contact lenses: the fluid layer between the lens and the cornea shields the corneal surface from environmental irritants, dryness, and mechanical damage, which is especially beneficial for severe ocular surface diseases.
High Oxygen Permeability and Hydration: The tissue-like material ensures that the scleral lens does not cause discomfort for extended periods of wear to patients due to its high breathability and constant hydration.
Customized Fit: In scleral lenses, each one is specifically designed to offer a highly individualized solution for complex eye conditions and the uniquely shaped eye of a patient.
Challenges and Considerations
While there are many advantages associated with scleral lenses, some challenges exist.
Cost: Custom-fit and fitting processes render scleral lenses to be much more costly than soft or rigid lenses. However, for many whose eye health problems are severe, the benefits far outweigh the cost.
Fitting Process: The fitting of scleral lenses takes much time and several return visits to an eye care provider. The individual benefit is guaranteed from the best fit of this particular lens; it takes time and effort.
Maintenance: Scleral lenses require proper hygiene and maintenance. Patients should clean the lenses and store them appropriately in solutions to avoid any complications or infections.
Learning Curve: Insertion and removal of scleral lenses are very challenging and provide a steep learning curve at the initiation point, particularly for first-time users of contact lenses. With experience and appropriate support from an eye care provider, most patients become proficient.
Scleral contact lenses seem a revolution for patients affected with complicated disorders of the cornea and for patients with a critical form of dry eyes. Their design is unique – truly so. They bring much more comfort, and better vision than any other method, while simultaneously protecting the cornea itself. This has been a quite good option for patients who do not find such relief in the existence of normal lenses. Although the fitting process is extremely labor-intensive and much costlier than the traditional lenses, the benefits of scleral lenses usually outweigh this investment for people with specific eye health requirements. It will be even more effective and more accessible to a wider group of patients as technology continues to improve.
