Integrated iseikonic equation for intraocular lens power calculations

I present a simplified equation to calculate the iseikonic intraocular lens power and the resultant refractive error needed to achieve iseikonia with 5% tolerance limits. Iseikonic lens power calculations are indicated in the presence of a unilateral cataract and a phakic fellow eye. Iseikonia is often achieved by leaving the operated eye more myopic than the fellow eye. The induced myopia, with 5% tolerance limits, ranges from -0.75 +/- 2.75 diopters (D) for a posterior chamber lens to -2.40 +/- 2.75 D for an anterior chamber lens.