Aspherical IOL designed with goal of aberration-free or neutral lens

San Diego-A new aspheric IOL, under development by Bausch & Lomb (Rochester, NY) is expected to provide optimum optical performance in pseudophakic eyes for a number of refractive conditions.

This IOL, in contrast with presently available IOLs, has no spherical aberration and will therefore not add to any pre-existing higher-order aberrations. Louis D. "Skip" Nichamin, MD, described the concept behind this IOL at the annual meeting of the American Society of Cataract and Refractive Surgery.

The problem with this, as Dr. Nichamin pointed out, is that the range of positive spherical aberration is significant and varies in the population. That, combined with the increase in corneas that have been altered by LASIK, makes use of this type of implant, at least in some patients, less than optimal.

This situation prompted Bausch & Lomb to design an "aberration-free or neutral lens" that does not contribute additional spherical aberration.