title: Comparison of corneal curvature and anterior chamber depth measurements using the manual keratometer, Lenstar LS 900 and the Pentacam.
abstract: OBJECTIVE
  The purpose of this study was to compare keratometry and anterior chamber depth (ACD) measurements from the Lenstar LS 900 (Haag-Streit AG, Switzerland) and the Pentacam (Oculus, Weltzar, Germany), and compare the keratometry readings of these two systems to a manual keratometer (MK), (Haag-Streit, Switzerland).
  
  
  METHODS
  In this prospective study, keratometry and ACD measurements were obtained in 50 eyes of 50 normal subjects with the Lenstar and the Pentacam. Keratometry was also measured using a MK. Correlation, comparison, and interdevice agreement was evaluated using intraclass correlation analysis, Wilcoxon test, and Bland-Altman plots.
  
  
  RESULTS
  The keratometry and ACD measurements obtained from the Lenstar and the Pentacam showed excellent correlation. The mean interdevice differences in mean keratometry (Km) for the Lenstar and the Pentacam, the Lenstar and the MK, and the Pentacam and the MK were 0.39 D, 0.10 D, and 0.30 D respectively; and the 95% limits of agreement (LoA) for Km were 0.04-0.82 D; -1.90-2.10 D; and -2.30-1.70 D, respectively. The mean interdevice difference in ACD for the Lenstar versus the Pentacam was 0.09 mm, with 95% LoA of 0.23-0.05 mm.
  
  
  CONCLUSIONS
  The ACD measurements obtained using the Lenstar and the Pentacam seem to be interchangeable, whereas, the keratometry measurements obtained using the Lenstar, Pentacam, and MK differ considerably, and are not interchangeable.
authors.affiliation: Department of Ophthalmology, Ankara University Faculty of Medicine, Ankara, Turkey.
authors.forename: Omür Ö
authors.initials: OÖ
authors.lastname: Uçakhan
authors.forename: Veysel
authors.initials: V
authors.lastname: Akbel
authors.forename: Zeynep
authors.initials: Z
authors.lastname: Bıyıklı
authors.forename: Ayfer
authors.initials: A
authors.lastname: Kanpolat
mesh_terms: D000328:Adult; D000867:Anterior Chamber / Q000033:anatomy & histology*; D001699:Biometry / Q000295:instrumentation; D003315:Cornea / Q000033:anatomy & histology*; D003941:Diagnostic Techniques, Ophthalmological / Q000295:instrumentation*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies
keywords: Anterior Chamber; Biometry; Cornea; Interferometry; Lenstar; Optical Low-coherence Reflectometry; Pentacam Scheimpflug