Early years: Visante OCT
Allow me to take you back to the future. With all of the options for fitting scleral lenses today, the fact remains that no instrument has been more important in the development of scleral lenses than the Visante OCT by Carl Zeiss. I purchased my first one in December 2007. Because of the international business, had the Visante not been there, I might have given up my scleral lens business. I actually measured some RGP contact lenses using the tools in the Visante and was able to accurately measure the curvatures – front and back – to within an acceptable tolerance using sags and chords. I would publish a paper on those experiments in 2008 (Eye & Contact Lens). That year saw a couple of curious visitors who went on to do their own research and publish their own papers on scleral shape using the Visante. By this time I had already applied for a U.S. Patent on using images for scleral lens design. My images found their way into publications by Bausch & Lomb about scleral lens fitting.
No More Trial Lenses
But my mission was not to find rules about scleral shape. My purpose was to be able to measure each eye and come up with the ideal fit for that eye and only that eye from measurements and mathematical formulae. Truform Optics was just starting up their own scleral lens business and they made ideal partners, always eager to try new things. For my part, I knew about Excel spreadsheets and the graphic and cubic spline functions and I created my own rudimentary CAD system from that. It was a modest beginning, measuring chords and sags in a couple of meridians. We progressed from spherical designs, to bitoric, to quadrant specific. I became quite facile at being able to crank out a respectable number of cases per week using that setup, and even designed a method of constraining the front surface to the back surface. This is why Laserfit lenses never really looked “perfect” like some other lenses. Instead, they faithfully followed the natural terrain of the sclera.
Baby Steps
I soon discovered just how limited the resident tools were in the Visante for lens design purposes, and had just begun to import the Visante scans into other software programs that had even greater assortment of tools, and then supplementing those with Excel functions. Word soon got out and I was invited to speak at what was one of the early Global Specialty Lens Symposia in 2009. Many of these slides have no narrative or explanation, but they represent various ways for designing lenses from the images, and I reveal them for what they are, the first baby steps in the history of designing scleral lenses from accurate high-resolution scans of the human eye for the improvement of fit and comfort. But this was only the beginning, not the middle nor the end of the story. To be continued.
2009 Global Specialty Lens Symposium
