Evaluation of Intraocular Lens (IOL) Formulae Utilizing Posterior Corneal Power in Post-Laser Vision Correction (LVC) Eyes

Abstract

Purpose To evaluate the accuracy of intraocular lens (IOL) power calculation formulae incorporating posterior corneal power vs traditional keratometry in post-laser vision correction (LVC) eyes undergoing cataract surgery. Patients and Methods This multicenter study (7 sites) combined retrospective chart review and prospective enrollment of adult cataract surgery patients with prior myopic or hyperopic LVC (one study eye per patient). Preoperative biometry was obtained by swept-source optical coherence tomography, and refractive prediction accuracy was compared across six IOL formulae (Barrett True K-AK, Barrett True K-TK, EVO 2.0-AK, EVO 2.0-TK, Haigis-TK, and Shammas-Cooke) in terms of trueness (mean refractive prediction error [RPE]), precision (RPE dispersion), and accuracy (absolute error metrics and proportion of eyes within ±0.5 D and ±1.0 D). Results A total of 154 eyes were included. The proportion of eyes within ±0.5 D of predicted refraction was highest with EVO 2.0-TK in both post-myopic (77%) and post-hyperopic (88%) LVC eyes, with Barrett True K-TK next highest (75% and 78%, respectively); in post-myopic eyes, EVO 2.0-TK was also the only formula whose mean RPE did not differ significantly from zero. Conclusions EVO 2.0-TK demonstrated the highest overall accuracy among the formulae evaluated in both post-myopic and post-hyperopic LVC eyes, while Barrett True K-TK also performed well, with both formulae achieving ≥75% of eyes within ±0.50 D in both LVC subgroups.