Comparison of Two Partial Coherence Interferometry Devices for Ocular Biometry

Background: An estimation of the repeatability of the Lenstar LS900 biometry parameters and comparison of these measurements to those evaluated with the IOLMaster were carried out. Patients and Methods: Axial length, corneal curvature, anterior chamber depth, central corneal thickness and lens thickness measurements were performed in 145 eyes using the Lenstar LS900, while axial length, corneal curvature and anterior chamber depth were measured using the IOLMaster. The repeatability coefficients and the coefficients of variation were assessed. The Bland-Altman plots and the regression analysis were applied to evaluate the differences between the two methods. Results: Axial length was the most repeatable parameter and lens thickness the most variable. Axial length and corneal curvature measurements by IOLMaster and Lenstar LS900 showed a good correlation (mean differences: 0.03 and 0.01 mm). Anterior chamber depth measurements by the two instruments resulted in a difference of 0.2mm (all p values < 0.0001). Regression analysis showed a highly significant correlation between measurements by the two methods. Correlation coefficients were: axial length 0.999, corneal curvature 0.983, anterior chamber depth 0.925 (p < 0.0001). Bland-Altman plots demonstrated that measurements by the tested devices were closely related without systematic effects in the range of evaluated data. Conclusion: Lenstar measurements yielded a high repeatability and correlate highly significant with the IOLMaster measurements.