Comparison of Biometric Measurements and IOL Power Calculation Between a Swept-Source OCT and an Optical Low-Coherence Reflectometry Biometer.

PURPOSE: To evaluate the comparability of biometric measurements obtained using the swept-source optical coherence tomography (SS-OCT) biometer (Anterion) and the optical low-coherence reflectometry (OLCR) biometer (Lenstar LS900).

METHODS

This observational study included 150 cataract patients undergoing preoperative biometry at the General University Hospital of Elche. Measurements from the Anterion and Lenstar LS900 were compared for axial length (AL), mean keratometry (Km), anterior chamber depth (ACD), lens thickness (LT), and central corneal thickness (CCT). Bland-Altman plots and statistical analyses were conducted to assess differences and correlations.

RESULTS

The mean AL measurements showed no significant difference between the two devices (mean difference -0.004 ± 0.053 mm, P = 0.420). ACD and LT measurements displayed statistically significant differences, with Anterion showing greater mean values (ACD difference: 0.054 ± 0.037 mm, P < 0.001; LT difference: 0.107 ± 0.079 mm, P < 0.001). Mean keratometry was significantly flatter by 0.074 ± 0.259D (P = 0.001) in Anterion compared to Lenstar, primarily due to differences in steep keratometry. No correlation was found between keratometry differences and corneal asphericity. Estimated intraocular lens (IOL) power for emmetropia was significantly higher using Anterion by 0.146 ± 0.398D (P < 0.001), necessitating an A-constant adjustment of approximately 0.16 to equal mean IOL power in both devices.

CONCLUSION

a good correlation was found between both biometers. However, due to the differences found between biometric measurements between devices, these two biometers should not be considered interchangeable and clinicians should adjust IOL constants accordingly. Future studies will be necessary to determine whether one biometer is superior to the other in terms of refractive outcome predictability.