ESCRS - POCAT595 - Intraocular Lens Power Calculation After Myopic Laser Vision Correction: Large Multicenter Real-World Comparative Analysis And The Role Of Posterior Corneal Curvature And Historical Data

Intraocular Lens Power Calculation After Myopic Laser Vision Correction: Large Multicenter Real-World Comparative Analysis And The Role Of Posterior Corneal Curvature And Historical Data

Published 2026 - 44th Congress of the ESCRS

Reference: POCAT595 | Type: Free paper | DOI: 10.82333/2s94-mq31

Authors: Dr David L. Cooke 1 , Dr Jasha A. Wendelstein 2 , Dr Kamran M. Riaz 3 , Prof. Dr Samuel Masket 4 , Dr Colya N. Englisch* 5

1Great Lakes Eye Care ,Saint Joseph,United States;Department of Neurology and Ophthalmology, College of Osteopathic Medicine, Michigan State University,East Lansing,United States, 2Department of Experimental Ophthalmology,Saarland University,Homburg,Germany;Institut für Refraktive und Ophthalmochirurgie (IROC) ,Zurich,Switzerland;Department of Ophthalmology,Ludwig Maximilian University,Munich,Germany, 3Dean McGee Eye Institute,University of Oklahoma,Oklahoma City,United States, 4Stein Eye Institute, Geffen School of Medicine, UCLA, Los Angeles,United States, 5Department of Experimental Ophthalmology,Saarland University,Homburg,Germany

Purpose

The primary aim was to evaluate the refractive predictive accuracy of legacy and modern intraocular lens (IOL) power calculation formulas, with and without incorporation of posterior corneal curvature (PCC), in a large multicenter real-world cohort of eyes with prior myopic laser vision correction (M-LVC). The secondary aim was to determine the incremental value of historical refractive data when applied to (1) standard formulas not specifically designed for post–M-LVC eyes with and without a novel history myopic modification (HMM), (2) M-LVC–specific formulas without PCC input, and (3) M-LVC–specific formulas incorporating PCC, in a “historical“ subset with complete biometric and historical information.

Setting

This retrospective cohort study used multicenter routine cataract surgery data from the United States aggregated in the Veracity database (Carl Zeiss Meditec AG). A total of 4,978 eyes with prior myopic laser vision correction (M-LVC) with swept-source biometry (IOLMaster 700) operated between 10/02/2017 and 08/20/2025, were evaluated for the primary aim. A subset of 80 eyes, operated between 01/01/2023 and 08/20/2025 with complete historical data, was analyzed for the secondary aim.

Methods

For the primary aim legacy formulas (Haigis-L, Shammas-PL), modern formulas with and without PCC (posterior keratometry [PK] or total keratometry [TK]) input (Barrett True K, EVO 2.0, Hoffer QST, Pearl DGS, K6), one formula without PCC (Shammas-Cooke), and one legacy formula with PCC (Haigis-TK) were used. For the secondary aim, 38 formula variants were assessed, including 12 standard formulas (with/without HMM) and four M-LVC formulas (Barrett True K, EVO 2.0, Pearl DGS, K6) in PCC- and history-based versions. HMM was derived from an independent training set: HMM (D) = 0.1445 × Ablation (D) + 0.063. Outcomes included mean absolute error (MAE, compared using heteroscedastic tests) and proportions within ±0.50 D / ±1.00 D of target.

Results

Modern no-history formulas outperformed legacy formulas. PCC significantly reduced MAE (p<0.0001). K6 had the lowest MAE overall. Among non-PCC formulas, EVO 2.0 ranked second; with PCC, Pearl DGS ranked second alongside Barrett True K and EVO 2.0. The two-variable Shammas-Cooke outperformed Haigis-L and Shammas-PL (both p<0.0001). In the “historical“ subset, PCC formulas counted among the top MAEs: EVO 2.0 (0.35 D), Barrett True K (0.37 D), Cooke K6 (0.37 D). History selectively improved no-PCC formulas and, via HMM, enhanced standard formulas (all p<0.01). Highest-ranking approaches (MAEs 0.35–0.38 D) combined PCC, history, or both, including HMM-corrected standard formulas; anterior-cornea-only formulas performed worse.

Conclusions

In this large real-world cohort, refractive accuracy after cataract surgery in post–M-LVC eyes was significantly improved with modern M-LVC formulas, particularly when PCC was used. When PCC measurements are available and included in modern IOL calculation platforms, routine recovery of historical refractive data offers minimal benefit. When PCC is unavailable, history-based approaches, including application of a HMM to standard formulas, not requiring particular online calculators, improve refractive outcomes.