Observing Lens Flexure by Altering Various Scleral Lens Parameters

Background: Scleral lenses have been used as far back as the 1800s as a treatment option for corneal irregularities. There have been many advancements in the design since then and through this study we hope to make another. The FDA approved gas permeable lens material will be modified to assess the flexure of the scleral lens. The modifications to the scleral lens will include modifying the central thickness, peripheral base curves, and landing zones. The ultimate goal is to create a lens design that has a thinner central thickness than current scleral lenses, thus allowing for better oxygen permeability to the cornea. Methods: The manufacturer, Valley Contax, will alter the lens parameters. The following procedures will be used to make the initial scleral lens fit: corneal biomicroscopy examination, corneal topography, and anterior segment optical coherence tomography (AS-OCT). Once all of the data is collected, a scleral lens with customized parameters will be fit on the patient’s eye. Afterwards, lens flexure will be evaluated using corneal topography and AS-OCT. Results: The topographical data of lenses A, B, and C revealed that lens B had the lowest initial delta k, lowest final delta k, and lowest percent change from initial to final. Lens B also showed the most consistent settling across the different lens zones. Lastly, lens B was rated as the most comfortable by the subjects, proving that thinner lenses are not always more comfortable. Conclusions: The research showed that thicker scleral lenses flex less over time compared those of a thinner design. It also showed that thicker scleral lenses settle more consistently than thinner.