Comparison of a new optical biometry with an optical low-coherence reflectometry for ocular biometry

Objective: To evaluate the repeatability and agreement of a new partial coherence interferometry optical biometer (AL-Scan, Nidek CO, Aichi, Japan) with optical low-coherence reflectometry device (Lenstar LS 900, Haag-Streit AG, Koniz, Switzerland). Methods: Three consecutive measurements with the 2 devices were performed by the same examiner in 65 eyes of 65 patients with cataract. Patients were divided into 2 groups: axial length (AL) between 22 and 26 mm (Group 1) and more than 26 mm (Group 2). Comparisons were performed for AL, anterior chamber depth (ACD), keratometry (K, over 2.4 mm diameter for AL-Scan and 2.3 mm diameter for Lenstar) and corneal diameter (CD). Repeatability was analyzed using the intraclass correlation coefficient (ICC) and the agreement was by the Bland-Altman method. Results: The repeatability of both devices was high for all biometry measurements (ICC over 0.970) in Group 1 and 2. The best repeatability was achieved for AL in each group. In both groups, the differences were statistically significant for all parameters (p < 0.05) except for the measurement of AL and CCT (p > 0.05). The Bland-Altman analysis showed good agreement between devices for all measurements in both groups. The closest agreement was for the AL measurements (ranged from -0.06 to 0.08 mm in Group 1 and 0.05-0.07 mm in Group 2). Conclusions: The new biometer provided excellent repeatability for all ocular biometry. In addition, there was good agreement between AL-Scan and Lenstar biometers for all parameters in cataractous patients with medium and long ALs. (C) 2016 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.