Comparison of Anterior Segment Measurements Obtained by Aladdin Optical Biometer and Sirius Corneal Topography

To assess the agreement of anterior segment parameter measurements derived from Aladdin optical biometer using optical low coherence interferometer and Sirius corneal topography using combined Scheimpflug-Placido disk.

Data obtained using the Aladdin and Sirius systems from 110 eyes of 59 subjects who had no health problems other than refractive errors were retrospectively evaluated. Anterior chamber depth (ACD), flat (K1) and steep (K2) keratometry readings, and white-to-white distance (WTW) measurements taken with both devices were noted.

The mean age of the patients was 47.31±18.57 years (range, 25 to 79 years). Mean ACD was 3.35±0.4 mm using Aladdin and 3.42±0.44 mm using Sirius. Mean difference in ACD was 0.075 mm greater with Sirius than Aladdin (p<0.001). K1 measurement obtained by Aladdin was an average of 0.409 D higher (p<0.001). No statistically significant differences were detected between the two devices in respect to K2 and WTW measurements (p=0.18, p=0.85 respectively). Pearson correlation analysis showed high correlation between the two devices for all measurements (r=0.985, 0.895, 0.961 and 0.766 for ACD, K1, K2 and WTW respectively; p<0.001).

Anterior segment parameters obtained by Aladdin optical biometer and Sirius anterior segment analysis system correlated well with each other and measurement differences between the devices were clinically negligible except for K1 values.