Power Calculations for Spherical and Toric Phakic IOLs

In this chapter, methods for the calculation of stigmatic and toric phakic IOL (TPIOL) powers are presented. These methods include calculations for the ideal TPIOL power for a given eye and desired postoperative spectacle power, the prediction of the postoperative spectacle power for a selected TPIOL power different from the ideal power, the calculation of an exchange TPIOL in the event of an unacceptable refractive surprise, and the calculation of a lens position parameter on a per-case basis to provide a means of building a data set to optimize the predictability of future cases. Sample calculations are presented to demonstrate the use of these equations.