title: Recovery of reliability by retest after a 5-minute interval in frequency doubling technology perimetry.
abstract: OBJECTIVE
  In frequency doubling technology (FDT) perimetry, the incidence of tests classified as unreliable is higher in the second-tested left eye than in the first-tested right eye when perimetry is performed without a rest period. The purpose of this study was to determine whether the incidence of unreliable results was reduced when the retest began after a 5-min rest period.
  
  
  METHODS
  The subjects were 978 residents of Miyoshi City, Japan, who underwent FDT perimetry during a medical checkup. FDT perimetry was always performed first on the right eye and then on the left eye without a rest interval. When the results were determined to be unreliable, FDT perimetry was repeated after a 5-min rest interval.
  
  
  RESULTS
  The perimetric results were determined to be unreliable in one eye of 119 subjects; the results of the first-tested right eye were unreliable in 24 (20.2%), and the results of the second-tested left eye were unreliable in 95 (79.8%) subjects. This difference in the incidence of reliability was significant (P<0.001). After a 5-min rest interval, the percentage of eyes with reliable results recovered to 92% of the right eyes and to 86% of the left eyes.
  
  
  CONCLUSIONS
  The incidence of unreliable results in FDT perimetry of the second-tested left eye was higher than that of the first-tested right eye when tests were performed without a rest interval. However, the incidence of unreliability in the eye was decreased when the retest was performed after a 5-min rest interval.
authors.affiliation: Department of Ophthalmology and Visual Sciences, Hiroshima University Graduate School of Biomedical Sciences, Hiroshima, Japan. htsuka@hiroshima-u.ac.jp.
authors.forename: Hidetoshi
authors.initials: H
authors.lastname: Tsukamoto
authors.affiliation: Department of Ophthalmology and Visual Sciences, Hiroshima University Graduate School of Biomedical Sciences, Hiroshima, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Mukai
authors.affiliation: Department of Ophthalmology, Tajimi Hospital, Tajimi, Japan.
authors.forename: Aiko
authors.initials: A
authors.lastname: Iwase
authors.affiliation: Department of Ophthalmology and Visual Sciences, Hiroshima University Graduate School of Biomedical Sciences, Hiroshima, Japan.
authors.forename: Hiromu K
authors.initials: HK
authors.lastname: Mishima
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D013997:Time Factors; D058609:Visual Field Tests / Q000379:methods* / Q000592:standards*; D014794:Visual Fields