Scleral Lenses

[DrG]

I am quite surprised that nobody has asked me about scleral lenses in this forum. There is more than one supplier of this lens. I have been working diligently with Truform Optics in Fort Worth in arriving at an advanced design in a wide range of sizes.

I'm happy to field any questions you may have.

[DrG]

This posted twice for some reason.

[DrG]

I'll start.

I believe that scleral lenses are commonly defined as a lens that rests entirely upon the sclera, thereby clearing the cornea. A scleral lens can be made to touch the cornea, though, but this defeats the purpose of such a large design. The diameters generally range from 16 mm to 26 mm. The larger size is needed to provide a sufficient load bearing area on the sclera, which is the white part of the eye outside of the cornea. If the area is too small, the lens will "dig into" the sclera and cut off the circulation. The fact that the lens does not touch the cornea makes it ideal for fragile and diseased corneas, and can actually promote healing of damaged epithelium. The single largest use for sclerals is in the treatment of keratoconus. The second is Stephen's Johnson Syndrome, I believe.

Ironically, scleral lens designs represent the earliest known contact lenses. The advent of corneal designs in the 1950's made contact lens fitting much simpler, and sclerals all but disappeared except in the UK. Early designs were made from acrylic material thermoset from a mold taken of the cornea, like a dental mold. This is the process I learned in optometry school. The advent of RGP materials have improved the performance of the lens, but also have made it more difficult to manufacture, as they cannot be heat formed.

One of the great lens pioneers responsible for resurrecting the scleral lens is Don Ezekiel of Gelflex in Australia. The scleral lens was further refined by the Boston Foundation for Sight. Med Lens Innovations is another manufacturer of scleral lenses in the U.S. The Jupiter Lens is a popular 16 mm design from Med Lens. Med Lens probably manufactures most of the scleral lenses used in the U.S. outside of the BFS. Practioners use fitting sets. Essilor Labs in Dallas also manufactures the Rob Breese (Med Lens) design under license.

Recently, a Fort Worth company, Truform Optics, has made their foray into scleral designs. They are a precision manufacturer with sophisticated capabilities and programming experience. I am working closely with them on a practical 16 mm design that is completely customized, and looks very promising indeed. I am also working on a novel design process to eliminate the need for trial lenses and to shorten the fitting process, also with promising results.

I have a newsletter, called GRS News that is distributed to a mailing list, in which I can go into greater detail. GRS is an abbreviation for Global Refractive Solutions, which is the name for my specialty lens practice. The next newsletter will be chock full of news, and will be published in the next week or so.