Intraocular Lens Power Calculation for Cataract Surgery in Eyes with Previous Radial Keratotomy

ABSTRACT

PURPOSE: To compare the accuracy of the intraocular lens (IOL) power calculation of clinical history method, with contact lens overrefraction method or computerized videokeratography method in the eyes with previous radial keratotomy (RK) METHODS: The medical records of 2 patients (3 eyes) who had previous RK, and recent phacoemulsification with posterior chamber lens implantation were retrospectively reviewed. All surgical procedures were performed by one surgeon. The power of implanted IOL was calculated by using clinical history method and SRK/T formula. Keratometric (K) value was measured with contact lens overrefraction and computerized videokeratography method before cataract extraction. Ideal keratometric value was calculated from the final postoperative spherical equivalent and the power of implanted IOL retrospectively, and then compared to K value of each method. RESULTS: Mean differences between the ideal K value and K value was 1.48 diopters in computerized videokeratography method, 2.54 diopters in clinical history method, and 3.65 diopters in contact lens overrefraction method, respectively. CONCLUSIONS: Unintentional hyperopia can be decreased by intentional postoperative myopia and obtaining K value by the computerized videokeratography method in cataract surgery of the eyes with previous radial keratotomy.