Comparison of keratometry and white-to-white measurements obtained by Lenstar with those obtained by autokeratometry and corneal topography

• Accurate keratometry and WTW measurements are distinctly important for correct diagnosis and treatment of anterior eye disorders.
• A good keratometry agreement was found between Lenstar and Tomey RC-5000 with narrow 95% LoA.
• The keratometry was no significantly different and the 95% LoA was narrow between Lenstar and Topolyzer.
• For WTW measurement, a good agreement was found between Lenstar and Tomey RC-5000, as well as between Lenstar and Topolyzer.

PurposeTo compare anterior eye segment measurements obtained using low optical coherence reflectometry (LENSTAR LS900, Haag-Streit), autokeratometry (RC-5000, Tomey) and corneal topography (Topolyzer, Wavelight).MethodsIn 46 healthy subjects, flat keratometry (Kf), steep keratometry (Ks), mean keratometry (Km) and white-to-white (WTW) distance were measured by Lenstar, Tomey RC-5000 and Topolyzer.ResultsKf and Km measurements of Lenstar were significantly steeper than Tomey RC-5000 (both p < 0.001), but the 95% LoA of them were narrow (−0.22 to 0.46 D, −0.16 to 0.36 D, respectively). There were no significant differences between the Kf and Km measurements of Lenstar and Topolyzer, with a narrow 95% LoA. There were no significant differences between the Ks measurements of Lenstar and Tomey RC-5000, and Lenstar and Topolyzer. A good agreement was found between them with 95% LoA of −0.40 to 0.56 D, and −0.56 to 0.64 D, respectively. WTW measurements with Lenstar were greater than those with Tomey RC-5000 and Topolyzer (p = 0.042, p < 0.01, respectively). A good agreement existed between the WTW obtained by Lenstar and Topolyzer, Tomey RC-5000, with 95% LoA ranging from −0.13 to 0.74 mm and −0.33 to 0.51 mm.ConclusionsGenerally good agreement was found between the Lenstar and Tomey RC-5000, Topolyzer for K and WTW measurements. In clinical practice, K and WTW measurements obtained by Lenstar and Tomey RC-5000, Topolyzer can be used interchangeably.