Efficacy of corneal curvature on the accuracy of 8 intraocular lens power calculation formulas in 302 highly myopic eyes

Abstract

Purpose: To investigate the effect of corneal curvature (K) on the accuracy of 8 IOL formulas in highly myopic eyes. Setting: Eye Hospital and School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, China. Design: Retrospective consecutive case series. Methods: 302 eyes (302 patients) were analyzed in subgroups based on the K value. The mean refractive error, mean absolute error (MAE), median absolute error (MedAE), root-mean-square absolute prediction error (RMSAE) and proportions of eyes within ±0.25 Diopter (D), ±0.50 D, ±0.75 D, ±1.00 D were statistical analyzed. Results: Emmetropia Verifying Optical (EVO) 2.0, Kane, and Radial Basis Function (RBF) 3.0 had the lower MAE (≤ 0.28) and RMSAE (≤ 0.348) and highest percentage of eyes within ±0.50 D (≥ 83.58%) in the flat (K ≤ 43D) and steep K (K > 45D) groups. Hoffer QST had the lowest MedAE (0.19), RMSAE (0.351) and the highest percentage of eyes within ±0.50 D (82.98%) in the normal K group (43 < K ≤ 45D). When AL ≤ 28 mm, all formulas showed close RMSAE values (0.322 to 0.373) in flat K group. When AL > 28 mm, RBF 3.0 achieved the lowest MAE (≤ 0.24), MedAE (≤ 0.17) and RMSAE (≤ 0.337) across all subgroups. Conclusions: EVO 2.0, Kane, and RBF 3.0 were the most accurate in highly myopic eyes with a flat or steep K. Hoffer QST is recommended for long eyes with normal K values. RBF 3.0 showed the highest accuracy when AL > 28 mm, independent of corneal curvature.

The effect of corneal power on the accuracy of 14 IOL power formulas

“…Kane and EVO2.0 also performed well and have good stability in flat cornea group. This finding was consistent with many previous studies [ 16 , 19 , 33 , 34 ].…”

“…The EVO2.0 and Hoffer QST also performed well. The RBF3.0 formula was found to have good results at different corneal curvatures in our previous studies in long eyes [ 33 ]. The K6 formula showed its effectiveness in both flat and steep corneas, although its efficacy in long eyes with abnormal corneal power was somewhat less pronounced [ 33 ].…”

“…The RBF3.0 formula was found to have good results at different corneal curvatures in our previous studies in long eyes [ 33 ]. The K6 formula showed its effectiveness in both flat and steep corneas, although its efficacy in long eyes with abnormal corneal power was somewhat less pronounced [ 33 ]. The Kane formula maintained its accuracy across eyes with abnormal corneal power, in both normal and long ALs, as supported by the results of this and previous studies [ 33 ].…”

Accuracy of 20 Intraocular Lens Power Calculation Formulas in Medium-Long Eyes

“…[ 30 ] proposed mean rank score for subgroup analysis (e.g., in terms of AL). Recently, most studies are based on outcomes of the root mean square absolute error (RMSAE) [ 31 – 33 ]. Then RMSAE is compared between formulas using the bootstrap-t method with Holm sequential correction [ 32 ].…”