Scleral lenses are life changing devices for a wide variety of patients. These custom devices help give crisp vision to people suffering from keratoconus, post-LASIK, corneal transplant, corneal scarring, high astigmatism and much more. They are extremely comfortable, stable, and easy to wear. They also offer relief from severe dry eye syndrome. This relatively new technology continues to evolve at a rapid pace and there are new options that utilize technology to improve fit, comfort and vision.
These options range from: good (diagnostic fit), to better (custom scan fit,) to best (impression mold design).
Diagnostic Fitting (Good)
This is the traditional method for fitting scleral lenses. Diagnostic (trial) lenses are placed on the eye in the office to determine the best fit and power for the patients eye. These designs continue to improve and are becoming more customizable each year, but still have limitations on how “fine-tuned” the fit can be based on manufacturer specifications.
Custom Scan Fitting (Better)
Thanks to a new piece of equipment here at Kirkwood Eye know as the Pentacam Corneo-Scleral Profiler, we can now scan the entire front surface of the eye including the cornea and surrounding sclera (the white part of the eye). Traditional topographers only measure the cornea. This is important because scleral lenses rest completely on the sclera. This technology allows us to scan the scleral topography (shape) and custom design a lens to match the unique curvature of each patients eye for an exacting fit in all meridians. This not only improves comfort and vision, it also reduces the need for remakes and additional office visits to “fine-tune” the design.
Impression Molded Design (Best)
This technique is similar to the process used for a dental mold. A bio-compatible compound is loaded in to a tray and placed against the ocular surface for about 90 seconds. There is no pain and it feels similar to wearing a contact lens. The compound hardens and is gently removed, leaving a perfect impression of the surface of the eye. The impressions are sent to a lab where scleral lenses are designed in a 3D environment to perfectly match the patient eye down to 2 microns of tolerance (a micron is one millionth of a meter). This design is great for anyone looking for a perfect fit from day one and is especially useful for people with scleral irregularities like glaucoma shunts or other elevations.
Andrew Biondo, OD, FSLS is the Primary Medical Director at Kirkwood Eye Associates in Kirkwood, MO. Serving the greater St. Louis area, Dr. Biondo has 12 years of experience as an eye care provider, health educator & consultant to the specialty contact lens industry. His special interests include contact lenses, dry eye disease, glaucoma, macular degeneration, laser eye surgery & preventive vision care.