Mehmet TETİKOĞLU, Hacı Murat SAĞDIK, Serdar AKTAŞ, FATİH ÖZCURA

Repeatability and Reproducibility of a New Partial Coherence Interferometer; AL-Scan Optic Biometer

The purpose of this study was to evaluate the intra-observer repeatability and inter-observer reproducibility of the ocular parameter measurements in cataract eyes using the new partial coherence interferometer, AL-Scan. Eighty-six eyes with cataracts were included in this prospective study. Axial length, average keratometry, anterior chamber depth, central corneal thickness, white-to-white distance and intraocular lens power calculation with the SRK-T formula were determined by two observers. The measurements were repeated by the same observers using the same AL-Scan unit on the same eye approximately 2 weeks later, just before surgery. Inter-observer reproducibility was excellent, with very high interclass correlation coefficients (˃0.984) for all measured parameters. Standard deviations (Sw) and coefficients of variation (CV) of the repeated measurements were low, which demonstrated high intra-observer repeatability, except for the central corneal thickness and white-to-white distance measurements (Sw≤0.224 ∞CV≤ 1.072). The precision of the measurements obtained by the AL-Scan biometer is highly reliable and observer-independent

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