A comparative study of eight intraocular lens calculation formulas.

A retrospective study of 183 eyes that had undergone extracapsular cataract extraction and posterior chamber intraocular lens (IOL) implantation was undertaken to compare the accuracy of eight IOL power calculation formulas (modified Binkhorst, Colenbrander, Gullstrand, Fyodorov-Galin-Linksz, Gill, Axt, Donzis-Kastle-Gordon and SRK regression). We found that the regression formulas were more accurate than the theoretical formulas, giving enough approximation to the ideal IOL as to assure its clinical use. We prefer the SRK formula because it is easier and it has a constant A that can be adapted in a personalized way to each surgical team.