title: Clinical performance of the Reichert AT550: a new non-contact tonometer.
abstract: The aim of the present study was to assess the level of accuracy for measurements of intra-ocular pressure (IOP) obtained with a new non-contact tonometer (NCT) the Reichert AT550. Measurements were compared against those obtained with the Reichert Xpert Plus, Goldmann applanation tonometer and Perkins tonometer. Thirty-five university students were assessed with the four tonometers in a randomised order, with non-contact tonometry performed first. Each of the four measurement devices had its own trained clinical observer. Plots of differences of IOP as a function of the mean for each pair of instruments were obtained. No statistically significant differences were found when comparing the AT550 NCT with contact applanation tonometry (AT) (p> 0.05), displaying the closest level of agreement (as represented by the lowest mean difference and the narrowest confidence interval) with the Goldmann tonometer (limits of agreement, 0.12+/-2.17). In conclusion, readings of IOP with the AT550 NCT are clinically comparable with those obtained with Goldmann tonometry in a population with IOP within the normal range.
authors.affiliation: Department of Physics (Optometry), School of Sciences, University of Minho, Braga, Portugal. jjorge@fisica.uminho.pt
authors.forename: J
authors.initials: J
authors.lastname: Jorge
authors.forename: J A
authors.initials: JA
authors.lastname: Díaz-Rey
authors.forename: J M
authors.initials: JM
authors.lastname: González-Méijome
authors.forename: J B
authors.initials: JB
authors.lastname: Almeida
authors.forename: M A
authors.initials: MA
authors.lastname: Parafita
mesh_terms: D000328:Adult; D005260:Female; D005901:Glaucoma / Q000175:diagnosis; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology*; D008297:Male; D015203:Reproducibility of Results; D014065:Tonometry, Ocular / Q000295:instrumentation* / Q000592:standards