Comparison of the keratometer and the lens bench in measuring intraocular lens power

Intraocular lenses (IOLs) from six manufacturers were measured on a Terry keratometer and on a calibrated lens bench for lens power. Differences between the two methods appeared when the IOLs were a different refractive index than polymethylmethacrylate (PMMA) and a shape other than planoconvex. These differences were consistent for ultraviolet absorbing PMMA and for meniscus lenses.