Comparison of Accuracy of Six Modern Intraocular Lens Power Calculation Formulas

Area of Science:

• Ophthalmology
• Biomedical Engineering
• Optics

Background:

• Cataract surgery is a common procedure for vision restoration.
• Accurate intraocular lens (IOL) power calculation is crucial for achieving desired refractive outcomes.
• Modern IOL power calculation formulas aim to improve refractive predictability.

Purpose of the Study:

• To compare the accuracy of six contemporary IOL power calculation formulas.
• To evaluate the prediction error of these formulas in standard cataract surgery.
• To analyze formula performance across different axial lengths (AL).

Main Methods:

• Retrospective review of 203 eyes undergoing phacoemulsification and IOL implantation.
• Biometric data obtained using partial coherence interferometry.
• Evaluation of Barrett Universal II (BUII), EVO 2.0, Hill-RBF 3.0, Hoffer QST, Kane, and PEARL-DGS formulas.
• Analysis of prediction error, correlation with AL and corneal power, and subgroup analysis by AL.

Main Results:

• No significant difference in absolute prediction errors among the six formulas overall.
• BUII and Hill-RBF 3.0 showed a higher percentage of eyes within ±0.50 D error compared to Hoffer QST (not significant after correction).
• BUII formula exhibited the highest accuracy, followed by PEARL-DGS, EVO 2.0, Kane, Hill-RBF 3.0, and Hoffer QST.
• Hoffer QST prediction error correlated significantly with AL; no formulas correlated with corneal power.

Conclusions:

• The six modern IOL power calculation formulas demonstrate comparable accuracy.
• Formula accuracy is consistent across various axial lengths.
• The BUII formula showed the highest performance index, indicating superior accuracy in this cohort.