title: Photographic Reading Center of the Idiopathic Intracranial Hypertension Treatment Trial (IIHTT): Methods and Baseline Results.
abstract: OBJECTIVE
  To describe the methods used by the Photographic Reading Center (PRC) of the Idiopathic Intracranial Hypertension Treatment Trial (IIHTT) and to report baseline assessments of papilledema severity in participants.
  
  
  METHODS
  Stereoscopic digital images centered on the optic disc and the macula were collected using certified personnel and photographic equipment. Certification of the camera system included standardization and calibration using a model eye. Lay readers assessed disc photos of all eyes using the Frisén grade and performed quantitative measurements of papilledema. Frisén grades by PRC were compared with site investigator clinical grades. Spearman rank correlations were used to quantify associations among disc features and selected clinical variables.
  
  
  RESULTS
  Frisén grades according to the PRC and site investigator's grades, matched exactly in 48% of the study eyes and 42% of the fellow eyes and within one grade in 94% of the study eyes and 92% of the fellow eyes. Frisén grade was strongly correlated (r > 0.65, P < 0.0001) with quantitative measures of disc area. Cerebrospinal fluid pressure was weakly associated with Frisén grade and disc area determinations (r ≤ 0.31). Neither Frisén grade nor any fundus feature was associated with perimetric mean deviation.
  
  
  CONCLUSIONS
  In a prospective clinical trial, lay readers agreed reasonably well with physicians in assessing Frisén grade. Standardization of camera systems enhanced consistency of photographic quality across study sites. Images were affected more by sensors with poor dynamic range than by poor resolution. Frisén grade is highly correlated with quantitative assessment of disc area. (ClinicalTrials.gov number, NCT01003639.).
authors.affiliation: Department of Ophthalmology Flaum Eye Institute, University of Rochester, Rochester, New York, United States.
authors.forename: William S
authors.initials: WS
authors.lastname: Fischer
authors.affiliation: Department of Neurology, University of Iowa, Iowa City, Iowa, United States 3Department of Ophthalmology, University of Iowa, Iowa City, Iowa, United States.
authors.forename: Michael
authors.initials: M
authors.lastname: Wall
authors.affiliation: Center for Human Experimental Therapeutics, University of Rochester, Rochester, New York, United States 5Department of Biostatistics and Computational Biology, University of Rochester, Rochester, New York, United States.
authors.forename: Michael P
authors.initials: MP
authors.lastname: McDermott
authors.affiliation: Mount Sinai Roosevelt Hospital, New York, New York, United States 7New York Eye and Ear Infirmary of Mount Sinai, New York, New York, United States.
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Kupersmith
authors.affiliation: Department of Ophthalmology Flaum Eye Institute, University of Rochester, Rochester, New York, United States.
authors.forename: Steven E
authors.initials: SE
authors.lastname: Feldon
mesh_terms: D000328:Adult; D015170:Cerebrospinal Fluid Pressure / Q000502:physiology; D005260:Female; D006801:Humans; D019586:Intracranial Hypertension / Q000150:complications / Q000175:diagnosis* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D009887:Ophthalmoscopy / Q000379:methods* / Q000592:standards; D009898:Optic Disk / Q000473:pathology*; D010211:Papilledema / Q000145:classification / Q000175:diagnosis* / Q000503:physiopathology; D010781:Photography / Q000379:methods*; D011446:Prospective Studies; D011932:Reading; D015203:Reproducibility of Results