Comparison of intraocular lens power calculation methods after myopic laser refractive surgery without previous refractive surgery data

Abstract

To compare the accuracy of intraocular lens (IOL) power calculation methods for post-myopic excimer laser surgery patients without previous refractive surgery data using the Holladay IOL Consultant Program and the American Society of Cataract and Refractive Surgery (ASCRS) IOL Power Calculator. Wang Vision Cataract and LASIK Center, Nashville, Tennessee, USA. Case series. Eight methods were used to calculate IOL power: Holladay 2 partial coherence interferometry (PCI)-K, Holladay 2 FlatK, Wang-Koch-Maloney, Shammas No-History, Haigis-L, ASCRS-Average, ASCRS-Min, and ASCRS-Max. The optimum IOL power corresponding to the target refraction was back-calculated using the stable post-cataract surgery refraction and implanted IOL power. Using the optimum IOL power, the predicted IOL power error and the resultant refractive error with each method were calculated and compared. The Holladay 2 FlatK method was most accurate for IOL power calculation, followed by the Holladay 2 PCI-K, ASCRS-Min, Wang-Koch-Maloney, ASCRS-Average, Shammas No-History, Haigis-L, and ASCRS-Max. Statistically significant differences were observed between Holladay 2 FlatK and Holladay 2 PCI-K (P<.05), Wang-Koch-Maloney and ASCRS-Average (P<.05), and Haigis-L and ASCRS-Max (P<.01). No statistically significant differences were observed between the Holladay 2 PCI-K, ASCRS-Min, and Wang-Koch-Maloney or between the ASCRS-Average, Shammas No-History, and Haigis-L (both P>.05). The Holladay 2 FlatK method provided the most accurate IOL power in eyes without previous myopic laser surgery data. If the Holladay IOL Consultant Program is unavailable, the ASCRS methods can be used; the ASCRS-Min represents the most accurate method.