title: Videokeratography database of normal human corneas.
abstract: OBJECTIVE
  To form a database of videokeratography patterns and quantitative indices describing normal human corneas using the absolute scale.
  
  
  METHODS
  Both eyes of 195 normal subjects were examined with a TMS-1 videokeratoscope. Videokeratographs were divided into 10 categories based on a classification scheme devised from the absolute scale and analysed with 10 quantitative indices devised to describe phenotypic features of keratoconus videokeratographs. Correlations were sought between videokeratograph patterns and quantitative indices. Additionally, data were analysed for differences in age, sex, and ethnicity.
  
  
  RESULTS
  For symmetric videokeratography patterns, analysis in the absolute scale was similar to a previous study done in the normalised scale. In the asymmetric categories, analyses differed markedly. Using the absolute scale and our classification scheme more variation in normal videokeratography patterns could be appreciated. There was good correlation between quantitative indices and videokeratography patterns. Neither videokeratography patterns nor indices differed significantly between sex, ethnic groups, or age using two way analysis of variance.
  
  
  CONCLUSIONS
  Pattern analysis of videokeratographs in the absolute scale using, a standard classification scheme, may be more useful in trying to determine whether a cornea is normal or represents subtle early disease than analysis in the normalised scale. Quantitative indices could remove the subjectivity from the decision making process thus facilitating universal reproducibility of videokeratography data interpretation.
authors.affiliation: Cornea Genetic Eye Medical Clinic, Cedars-Sinai Medical Center, Los Angeles 90048, USA.
authors.forename: Y S
authors.initials: YS
authors.lastname: Rabinowitz
authors.forename: H
authors.initials: H
authors.lastname: Yang
authors.forename: Y
authors.initials: Y
authors.lastname: Brickman
authors.forename: J
authors.initials: J
authors.lastname: Akkina
authors.forename: C
authors.initials: C
authors.lastname: Riley
authors.forename: J I
authors.initials: JI
authors.lastname: Rotter
authors.forename: J
authors.initials: J
authors.lastname: Elashoff
mesh_terms: D000328:Adult; D003315:Cornea / Q000033:anatomy & histology*; D003936:Diagnosis, Computer-Assisted / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D018715:Microscopy, Video / Q000379:methods*; D010641:Phenotype; D012016:Reference Values