When routine methods are used in intraocular lens (IOL) power calculation in cataractous eyes that have had undergone incisional or photoablative keratorefractive surgery, refractive errors are frequently seen following the cataract surgery. The 2 important sources of error in biometry are the incorrect determination of the corneal power (inability to measure the anterior corneal curvature correctly and inability to convert this measurement to the total corneal power, due to changed refractive index of the cornea) and incorrect estimation of the effective lens position in IOL power calculation formulas.
Keywords: Intraocular lens, keratorefractive surgery, LASEK, LASIK, PRK, RK