title: Frequency doubling technology for earlier detection of functional damage in standard automated perimetry-normal hemifield in glaucoma with low-to-normal pressure.
abstract: OBJECTIVE
  To compare the longitudinal change of frequency doubling technology (FDT) perimetry and standard automated perimetry (SAP) results in SAP-normal hemifield in open-angle glaucoma (OAG) eyes with low-to-normal intraocular pressure (IOP).
  
  
  METHODS
  FDT perimetry with the N-30 full threshold protocol and SAP using the Humphrey Field Analyzer with the 30-2 Swedish Interactive Threshold Algorithm-standard protocol were periodically performed for at least 3 years in 39 eyes of 39 OAG patients with low-to-normal IOP and visual field damage confined to only one hemifield. The time courses of the mean of the threshold values of FDT and the mean of total deviations (TDs) in SAP-normal and SAP-abnormal fields were analyzed using a linear mixed model.
  
  
  RESULTS
  The average follow-up was 4.9 years and the average IOP during follow-up was 12.6 mm Hg with or without medication. The aging effect-corrected rate of change in the mean FDT threshold values was significantly negative (P=0.004) in the SAP-normal hemifield, whereas that of mean of TD values by SAP did not significantly differ. In the SAP-abnormal hemifield, the rate of change was significantly negative for both tests (P<0.001). The mean of the slope of the mean TD values in the SAP-abnormal hemifield was significantly more negative than that in the SAP-normal hemifield (P=0.011), whereas that of the mean FDT threshold values showed no significant difference between the 2 hemifields.
  
  
  CONCLUSIONS
  FDT is useful for monitoring functional damage in the SAP-normal hemifield in OAG eyes with low-to-normal IOP.
authors.affiliation: Department of Ophthalmology, University of Tokyo Graduate School of Medicine, Tokyo, Japan. snakagawa-tky@umin.ac.jp
authors.forename: Suguru
authors.initials: S
authors.lastname: Nakagawa
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Murata
authors.forename: Hitomi
authors.initials: H
authors.lastname: Saito
authors.forename: Hisae
authors.initials: H
authors.lastname: Nakahara
authors.forename: Naomi
authors.initials: N
authors.lastname: Mataki
authors.forename: Atsuo
authors.initials: A
authors.lastname: Tomidokoro
authors.forename: Aiko
authors.initials: A
authors.lastname: Iwase
authors.forename: Makoto
authors.initials: M
authors.lastname: Araie
mesh_terms: D000465:Algorithms; D005500:Follow-Up Studies; D005902:Glaucoma, Open-Angle / Q000175:diagnosis* / Q000503:physiopathology; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology*; D057066:Low Tension Glaucoma / Q000175:diagnosis / Q000503:physiopathology; D008875:Middle Aged; D009898:Optic Disk / Q000473:pathology*; D009901:Optic Nerve Diseases / Q000175:diagnosis* / Q000503:physiopathology; D014786:Vision Disorders / Q000175:diagnosis* / Q000503:physiopathology; D058609:Visual Field Tests / Q000379:methods*; D014794:Visual Fields