EVALUATION OF PREDICTIVE ACCURACY OF FIVE INTRAOCULAR LENS POWER CALCULATION FORMULAE IN CATARACTOUS EYES WITH SHORT AXIAL LENGTH

Abstract Purpose: To compare the predictive accuracy of five intraocular lens (IOL) power calculation formulae SRK/T, Hoffer Q, Holladay I, Binkhorst, and Barrett Universal II in cataract patients with short axial length (<22.00 mm). Methods: In this prospective observational study, 65 eyes with axial length <22.00 mm undergoing phacoemulsification with posterior chamber IOL implantation were included. Preoperative biometry (axial length, keratometry, anterior chamber depth) was obtained using standard immersion ultrasound. IOL power was calculated using SRK/T, Hoffer Q, Holladay I, Binkhorst, and Barrett Universal II formulae. The actual postoperative spherical equivalent (SE) was measured at 6 weeks. Absolute prediction errors (AE) were determined for each formula and compared statistically. Results: The mean age was 62.81 ± 5.17 years, with a female predominance. Significant postoperative visual improvement was observed. Hoffer Q showed the lowest mean AE (0.09± 0.09D), indicating the highest predictive accuracy, followed by Barrett Universal II (0.128 ± 0.164) and Holladay (0.227 ± 0.139). SRK/Theoretic and Binkhorst formulae demonstrated higher errors. Conclusion: Hoffer Q is the most accurate formula for IOL power calculation in short axial length eyes, with Barrett Universal II as a reliable alternative.