Comparison of axial length measurements with RS-1 spectral domain optical coherence tomography and OA-2000 biometer

AIM: To determine the utility of the RS-1 spectral domain optical coherence tomography (SD-OCT), which incorporates an "OCT Analysis Correction Parameter" for approximating axial length, in comparison with measurements obtained from the OA-2000. METHODS: Twenty-five right eyes of healthy individuals were included. Two horizontal line scans were conducted using the RS-1, and OCT Analysis Correction Parameters were recorded. Axial length was measured twice per eye using the OA-2000. Correlation between devices was assessed using Pearson correlation coefficient, coefficient of repeatability (CR%), and Bland-Altman analysis. RESULTS: High correlation was found between axial length measurements from RS-1 and OA-2000 (r=0.986, P<0.0001). The coefficient of repeatability was 1.56% for RS-1 and 0.115% for OA-2000. Mean axial length was 25.12 +/- 1.38 mm for RS-1 and 24.90 +/- 1.54 mm for OA-2000, with RS-1 showing a statistically significant larger value (paired t-test, P=0.0009). CONCLUSION: The axial length measurements of RS-1 demonstrate a strong positive correlation with those from the OA-2000. This indicates that it could potentially be used to forecast scan ranges and choose suitable databases according to axial length categories.