Comparison of a new optical biometer using swept-source optical coherence tomography and a biometer using optical low-coherence reflectometry

PurposeTo investigate agreement between the IOLMaster 700 based on swept-source optical coherence tomography (SS-OCT) and the Lenstar LS 900 based on optical low-coherence reflectometry (OLCR).SettingPrivate practice, Castrop-Rouxelle, Germany.DesignProspective evaluation of diagnostic test.MethodsAxial length (AL), keratometry (K), anterior chamber depth (corneal epithelium to lens) (ACD), lens thickness, and central corneal thickness (CCT) were measured in 183 eyes of 183 patients. Analyses used a paired t test, Pearson correlation coefficient (r), and Bland-Altman plots. Intraocular lens (IOL) power calculations were compared using the Hoffer Q, Holladay 1, and SRK/T formulas.ResultsThe difference in the mean AL between SS-OCT and OLCR was statistically significant but clinically insignificant (23.61 mm ± 1.27 [SD] and 23.60 ± 1.27 mm, respectively; P < .0001); the agreement and correlation were excellent. The mean K with OLCR was flatter by 0.02 diopter (D) than the mean K with SS-OCT, 43.82 ± 1.43 diopters (D) and 43.84 ± 1.43 D, respectively; the difference was not statistically significant. The mean ACD with SS-OCT was deeper by 0.03 mm than the mean ACD with OLCR, 3.22 ± 0.44 mm and 3.19 ± 0.44 mm, respectively; the difference was statistically significant (P < .001) but clinically insignificant. The differences in the mean lens thickness (OLCR 4.63 ± 0.44 mm and SS-OCT 4.59 ± 0.43 mm) and the mean CCT (OLCR 559 ± 37 μm and SS-OCT 554 ± 36 μm) were not statistically significant. There was no statistically significant difference between the median absolute errors of the 3 formulas.ConclusionsAgreement between SS-OCT and OLCR was very good. The clinically insignificant but statistically significant differences in AL, ACD, and lens thickness did not reflect a statistically significant difference in IOL power calculation using 3 third-generation formulas.Financial DisclosureProprietary or commercial disclosures are listed after the references.