title: Detection of glaucoma progression by population and individual derived variability criteria.
abstract: OBJECTIVE
  Ocular imaging devices provide quantitative structural information that might improve glaucoma progression detection. This study examined scanning laser polarimetry (SLP) population-derived versus individual-derived cut-off criteria for detecting progression.
  
  
  METHODS
  Forty-eight healthy, glaucoma suspect and glaucoma subjects, providing 76 eyes were used. All subjects had reliable visual field (VF) and SLP scans acquired at the same visits from ≥4 visits. VF progression was defined by guided progression analysis (GPA) and by the VF index. SLP measurements were analysed by fast mode (FM) GPA, compared with the population rate of progression, and extended mode (EM) GPA, compared with the individual variability. The agreement between progression detection methods was measured.
  
  
  RESULTS
  Poor agreement was observed between progression defined by VF and FM and EM. The difference in temporal-superior-nasal-inferior-temporal (TSNIT) average rate of change between VF defined progressors and non-progressors for both FM (p=0.010) and EM (p=0.015) was statistically significant.
  
  
  CONCLUSIONS
  There is poor agreement between VF and SLP progression regardless of the use of population derived or individual variability criteria. The best SLP progression detection method could not be ascertained, therefore, acquiring three SLP scans per visit is recommended.
authors.affiliation: UPMC Eye Center, Eye & Ear Institute, Ophthalmology and Visual Science Research Center, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA.
authors.forename: Lindsey S
authors.initials: LS
authors.lastname: Folio
authors.forename: Gadi
authors.initials: G
authors.lastname: Wollstein
authors.forename: Jacek
authors.initials: J
authors.lastname: Kotowski
authors.forename: Richard A
authors.initials: RA
authors.lastname: Bilonick
authors.forename: Yun
authors.initials: Y
authors.lastname: Ling
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Ishikawa
authors.forename: Larry
authors.initials: L
authors.lastname: Kagemann
authors.forename: Joel S
authors.initials: JS
authors.lastname: Schuman
mesh_terms: D000368:Aged; D018450:Disease Progression; D005901:Glaucoma / Q000175:diagnosis*; D006068:Gonioscopy; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology; D008875:Middle Aged; D009412:Nerve Fibers / Q000473:pathology*; D009798:Ocular Hypertension / Q000175:diagnosis; D009898:Optic Disk / Q000473:pathology*; D009901:Optic Nerve Diseases / Q000175:diagnosis*; D015203:Reproducibility of Results; D012165:Retinal Ganglion Cells / Q000473:pathology*; D057109:Scanning Laser Polarimetry / Q000379:methods*; D014792:Visual Acuity / Q000502:physiology; D058609:Visual Field Tests; D014794:Visual Fields / Q000502:physiology