title: Quantitative grading of nerve fiber layer photographs.
abstract: OBJECTIVE
  The authors have developed a simple method for semi-quantitative grading of atrophy of the peripapillary nerve fiber layer (NFL) in black and white photographs.
  
  
  METHODS
  An experienced observer read sets of NFL photographs using a four-level grading system. Five observers with varying levels of experience at ophthalmic examination were taught the grading system in approximately 4 hours, and their readings were compared with those of the expert.
  
  
  RESULTS
  The reproducibility of readings by an experienced observer was excellent. The validity of the grading system was confirmed by comparisons to visual field findings, as well as to cup-to-disc ratios in the same eyes. The agreement with the expert by the five trained graders was good.
  
  
  CONCLUSIONS
  Grading of the NFL could be useful both to monitor development of early glaucoma damage clinically and to measure progression of glaucoma damage in clinical trials research. The grading system can be taught readily to other observers.
authors.affiliation: Dana Center for Preventive Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, MD 21205.
authors.forename: H A
authors.initials: HA
authors.lastname: Quigley
authors.forename: M
authors.initials: M
authors.lastname: Reacher
authors.forename: J
authors.initials: J
authors.lastname: Katz
authors.forename: E
authors.initials: E
authors.lastname: Strahlman
authors.forename: D
authors.initials: D
authors.lastname: Gilbert
authors.forename: R
authors.initials: R
authors.lastname: Scott
mesh_terms: D000328:Adult; D000368:Aged; D001284:Atrophy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007429:Intraocular Pressure; D008297:Male; D008875:Middle Aged; D009412:Nerve Fibers / Q000473:pathology*; D015588:Observer Variation; D009798:Ocular Hypertension / Q000473:pathology*; D009900:Optic Nerve / Q000473:pathology*; D010781:Photography; D011237:Predictive Value of Tests; D015203:Reproducibility of Results