Anterior hydrogel lens deposits: polished vs. unpolished surfaces

Traditionally, lathe cut hydrogel lenses receive both back and front surface polishing to eliminate any surface irregularities that might serve as potential attachment sites for lens deposits or even microorganisms. However, with the advent of newer more technologically advanced lathing equipment, the need for lens polishing may require renewed justification. This study sought to compare, by scanning electron microscopy (SEM), anterior lens surface deposit formation on polished and unpolished 55% water hydrogel lenses. A total of 10 subjects wore in 1 eye (control) a lens with both front and back lens surfaces polished and on the other eye (test) a lens with only the back lens surface polished for a period of 2 weeks on a daily wear basis. Each lens was then scanned (using SEM), with 3 separate regions photographed at 30x using a 10 kV electron source. Using a Wilcoxon Signed-Ranks test on the differences between average deposit ratings for the polished and the unpolished lenses, by subject pair, we failed to reject the null hypothesis that the difference was zero.