Repeatability and Similarity of Biometric Measurements by a New Swept-source Optical Coherence (OA 2000) and the Partial Coherence Interferometry Device (IOL Master) as Reference

To investigate the repeatability and similarity of measurement of Lens thickness (LT), Anterior Chamber Depth (ACD), Axial Length (AL), and keratometry (K) by new OA-2000 device and to compare it with IOL Master 500.

In this observational cross-sectional study, patients with cataract in one or both eyes were included. Biometery measurements including AL, ACD, LT, and K were obtained by the OA-2000 (software version 1.0R) and IOLMaster 500 (software version 5.4) devices in a random sequence. Two measurements were obtained for each device. Test-retest reliability coefficients for AL, ACD, and K readings was used to show repeatability. The Bland-Altman limits-of-agreement (LoA) method was used to assess the agreement in AL, ACD, and K readings between the 2 biometers.

Fifty-eight eyes (46 right eyes and 12 left eyes) of 58 patients (31 male and 27 female, mean age 61.4 ± 8.3) with cataracts were included in this study. Based on test retest repeatability, coefficient of variation (CV) for different parameters measured by OA2000 showed good to excellent reliability (CV for ACD: 88%, CV for K: 90%, CV for LT: 83%, and CV for AL: 99%). Bland-Altman analysis indicated small mean difference (0.01 for axial length, 0.11 for anterior chamber depth, 0.1 and 0.07 for keratometry) and narrow Limits of Agreement (LoA) for all comparisons (95% LoA: -0.09 -0.1for AL, -0.33 – 0.54 for ACD, -1.8 – 2.1for K1, -0.75 – 0.6 for K2).

The results of this study demonstrated the excellent repeatability of the new swept-source OCT (OA 2000) for measurement of biometric data for IOL power calculation, with good agreement with the standard PCI biometer (IOLMaster 500).