Performance Of The Escrs Calculator With K And Tk Values In Steep And Flat Corneas

To compare the utility of K and TK values in extreme K eyes by testing four third-generation and six multivariable IOL power calculation formulas.

Single tertiary academic center. 

“Flat” and “Steep” K values were defined as ≤42D and ≥48D. Eyes with extreme K undergoing phacoemulsification with non-toric monofocal IOLs and postoperative CDVA ≥20/30 were included. Exclusion criteria were prior refractive surgery, corneal ectasia, scarring, trauma, CME, or poor follow-up. SS-OCT biometry (IOLMaster 700) captured K and TK, which were substituted into four third-generation formulas (Holladay 1, Hoffer Q, SRK/T, Haigis) and six multivariable formulas (Barrett Universal II, Cooke K6, EVO 2.0, Kane, Hill RBF 3.0, PEARL-DGS) to calculate refractive prediction errors. MAE and RMSE assessed outcomes.

Results for the present study are still being analyzed. Full comparative performance of K vs TK among formulas and by flat/steep strata reporting MAE//RMSE using heteroscedastic testing for testing statistical significance will be presented.

This study will define whether TK confers a clinically meaningful advantage over conventional K in extreme corneas and if specific formula(s) improve accuracy with K or TK values.