Comparison Of The Ascrs Iol Calculator (Aic) Predictability For Eyes With Prior Myopic Lasik Or Prk, To 2 Other Methods: A Consecutive Case Series

 To evaluate the accuracy of 3 intraocular lens (IOL) power calculation techniques and formulas in cases with prior myopic LASIK or PRK.

Laservision Ambulatory Surgical Unit, Athens, Greece

In this consecutive case series, 20 eyes of 12 patients, with prior LASIK or PRK were evaluated. IOL calculation for the Acrysoft aspheric toric was performed: besides the AIC 2022-2024 internet-available version, with the IOLMaster 700: axial length, total cornea power and Holladay1 formula (IMH1), and our own proprietary modified technique using either IOLMaster 700,Lenstar or Pentacam AXL wave axial length measurement combined with Pentacam HR total corneal power at 4.5mm, by the Holladay1 formula, an adjusted A constant and a pre-fixed fudge factor of +2 Diopters (AthensFormula) the later two formulas providing a single IOL power, not a range as the AIC.The differences in the calculation errors of the 3 formulas were compared.

Results: The prediction error of the AthensFormula was superior (statistically significantly less) than the AIC and IMH1. Of the later two the IMH1 superior to the AIC. All cases were evaluated at 3 months post uneventfull clear cornea catarct extraction and toric IOL implantation

Conclusions: IOL calculation for eyes with prior myopic LASIK or PRK remains challenging. This small case series appears to offer an alternative calculator- potentially more accurate- that is simple, and can be applied with 2 measurements: 1- axial length and anterior chamber depth by any current interferometry device and 2- anterior chamber depth and total corneal power by Scheimpflug tomography.