title: Evaluation of newly-developed aniseikonia testing method based on space eikonometry.
abstract: BACKGROUND
  We have developed a new aniseikonia testing method based on the space eikonometry (ATSE) principle. The purpose of this study was to compare aniseikonia obtained by the ATSE to that of the conventional new aniseikonia tests (NAT), which is commonly used in Japan.
  
  
  METHODS
  Thirty normal subjects (mean age: 22.8 years) without ocular disease except for refractive errors were studied. All of the subjects had normal binocular single vision with stereopsis. We excluded subjects with refractive errors greater than 1.00 D cylinder or anisometropia (spherical equivalent) greater than 1.00 D. We simulated overall aniseikonia of five and 10 per cent with afocal size lenses (HOYA, Tokyo, Japan) placed in the optical path of the fully corrected right eye. We measured aniseikonia three times with either the ATSE or NAT and the averages were used for the statistical analyses.
  
  
  RESULTS
  The mean and standard deviation (SD) of aniseikonia determined by the ATSE was 5.1 ± 0.8 per cent with the five per cent afocal lens and 10.1 ± 0.8 per cent with the 10 per cent afocal lens. Aniseikonia was 2.8 ± 1.3 per cent with the five per cent afocal lens and 6.0 ± 2.5 per cent with the 10 per cent afocal lens by the NAT. The mean error was + two per cent of the theoretical value by the ATSE and -42 per cent by the NAT for both afocal lenses.
  
  
  CONCLUSIONS
  We recommend the use of the new ATSE for quantitative determination of aniseikonia, as it is more accurate than the NAT.
authors.affiliation: Department of Orthoptics, Teikyo University Faculty of Medical Technology, Tokyo, Japan.|Department of Ophthalmology, Teikyo University School of Medicine, Tokyo, Japan.
authors.forename: Kakeru
authors.initials: K
authors.lastname: Sasaki
authors.affiliation: Department of Orthoptics, Teikyo University Faculty of Medical Technology, Tokyo, Japan.
authors.forename: Katsuhiko
authors.initials: K
authors.lastname: Kobayashi
authors.affiliation: Department of Ophthalmology, Teikyo University School of Medicine, Tokyo, Japan.
authors.forename: Chie
authors.initials: C
authors.lastname: Usui
authors.affiliation: Department of Orthoptics, Teikyo University Faculty of Medical Technology, Tokyo, Japan.|Department of Ophthalmology, Teikyo University School of Medicine, Tokyo, Japan.
authors.forename: Takao
authors.initials: T
authors.lastname: Hayashi
authors.affiliation: Department of Ophthalmology, Teikyo University School of Medicine, Tokyo, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Kawashima
authors.affiliation: Department of Ophthalmology, Teikyo University School of Medicine, Tokyo, Japan.
authors.forename: Yusa
authors.initials: Y
authors.lastname: Tane
authors.affiliation: Department of Ophthalmology, Teikyo University School of Medicine, Tokyo, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Mizota
mesh_terms: D000328:Adult; D000839:Aniseikonia / Q000175:diagnosis*; D003941:Diagnostic Techniques, Ophthalmological; D005260:Female; D006801:Humans; D008297:Male; D013028:Space Perception
keywords: aniseikonia; aniseikonia inspector; new aniseikonia tests; space eikonometer