Evaluation Of Escrs Online Calculator Performance By Usıng Optical Biometry And Scheimpflug Camera
Published 2025 - 43rd Congress of the ESCRS
Reference: PO459 | Type: Free paper | DOI: 10.82333/cnj6-2667
Authors: Lars Mackenbrock 1 , Grzegorz Łabuz 2 , Nikola Henningsen 2 , Gerd Auffarth 1 , Ramin Khoramnia 3 , Timur Yildirim* 1
1Department of Ophthalmology,University Hospital Heidelberg ,Heidelberg,Germany, 2Department of Ophthalmology,University Hospital Heidelberg,Heidelberg,Germany, 3Department of Ophthalmology,University Hospital Dresden,Dresden,Germany
Purpose
To evaluate the accuracy of ESCRS online calculator based on keratometry values at different zones obtained by optical biometry and corneal topography
Setting
Departman of Ophthalmology ,Zonguldak Bülent Ecevit University Hospital ,Zonguldak,Türkiye
Methods
A total of 120 patients who underwent cataract surgery with SA60AT IOL implantation were included in the study. Preoperative IOL power was calculated using optical biometry with standard keratometry and the SRK/T formula. SimK values were obtained using a Scheimpflug camera combined with Placido-disk corneal topography at 3 -, 5-, and 7-mm zones. The postoperative refractive outcomes were evaluated at 1. months using the ESCRS IOLcalculator module. Key metrics included mean prediction error (MPE), mean absolute error (MAE), median absolute error (MedAE), and the percentage of eyes within ±0.5 D, ±1.0 D, and ±2.0 D of target refraction.
Results
The MedAE values showed similar patterns across all formulas, with SRK/T having the lowest (0.25D) and EVO the highest (0.45D). Other values were: Hill-RBF (0.28D), Pearl-DGS (0.34D), Hoffer QST (0.34D), Kane (0.38D), Cooke K6 (0.38D), and Barrett (0.41D). While all were significantly above zero (p < 0.001), no significant differences were found between them (p = 0.536). The Hill-RBF formula performed best, with 87.5% of eyes within ±0.5D of the predicted refraction. Keratometric measurements at SimK(45,06D), 3-(45,19D), 5-(45,22D), and 7-mm(45,22D) zones showed no statistically significant differences among the formulas based on MAE values (p > 0.05).
Conclusions
The use of the ESCRS IOL calculator module (https://iolcalculator.escrs.org) has led to reduced prediction errors and a higher percentage of eyes achieving target refractive outcomes. Compared to the SRK/T formula, the Hill-RBF formula demonstrated statistically significant superiority, with the highest number of eyes falling within ±0.5 D of the predicted refractive error (PE). Additionally, all keratometric values obtained from the Scheimpflug camera combined with Placido-disk corneal topography have been shown to be reliably applicable in IOL calculations using newer-generation formulae.