title: Accuracy and validity of IK4 handheld video keratometer measurements in children.
abstract: The infant keratometer (IK4) is a custom handheld instrument that was designed specifically to allow measurement of corneal astigmatism in infants as young as 6 months of age. In this study, accuracy of IK4 measurements with the use of standard toric surfaces was within 0.25 D. Validity measurements obtained in 860 children aged 3-7 years demonstrated slightly greater astigmatism measurements in the IK4 than in the Retinomax K+. Measurement success was 98% when the IK4 was used. The IK4 may prove to be clinically useful for screening children as young as 3 years of age at high risk for corneal astigmatism.
authors: Department of Ophthalmology and Vision Science, University of Arizona, Tucson, Arizona 85711, USA. emharvey@u.arizona.edu
authors: Erin M
authors: EM
authors: Harvey
authors: Joseph M
authors: JM
authors: Miller
authors: Jim
authors: J
authors: Schwiegerling
authors: Candice E
authors: CE
authors: Clifford-Donaldson
authors: Tina K
authors: TK
authors: Green
authors: Dawn H
authors: DH
authors: Messer
authors: Velma
authors: V
authors: Dobson
mesh_terms: D000367:Age Factors; D001251:Astigmatism / Q000175:diagnosis*; D002138:Calibration / Q000592:standards; D002648:Child; D002675:Child, Preschool; D019781:Corneal Topography / Q000295:instrumentation* / Q000592:standards*; D004867:Equipment Design; D006801:Humans; D008403:Mass Screening / Q000295:instrumentation / Q000592:standards; D015203:Reproducibility of Results