title: Development and validation of an associative model for the detection of glaucoma using pupillography.
abstract: OBJECTIVE
  To develop and validate an associative model using pupillography that best discriminates those with and without glaucoma.
  
  
  METHODS
  A prospective case-control study.
  
  
  METHODS
  We enrolled 148 patients with glaucoma (mean age 67 ± 11) and 71 controls (mean age 60 ± 10) in a clinical setting. This prototype pupillometer is designed to record and analyze pupillary responses at multiple, controlled stimulus intensities while using varied stimulus patterns and colors. We evaluated three approaches: (1) comparing the responses between the two eyes; (2) comparing responses to stimuli between the superonasal and inferonasal fields within each eye; and (3) calculating the absolute pupil response of each individual eye. Associative models were developed using stepwise regression or forward selection with Akaike information criterion and validated by fivefold cross-validation. We assessed the associative model using sensitivity, specificity and the area-under-the-receiver operating characteristic curve.
  
  
  RESULTS
  Persons with glaucoma had more asymmetric pupil responses in the two eyes (P < 0.001); between superonasal and inferonasal visual field within the same eye (P = 0.014); and smaller amplitudes, slower velocities and longer latencies of pupil responses compared to controls (all P < 0.001). A model including age and these three components resulted in an area-under-the-receiver operating characteristic curve of 0.87 (95% CI 0.83 to 0.92) with 80% sensitivity and specificity in detecting glaucoma. This result remained robust after cross-validation.
  
  
  CONCLUSIONS
  Using pupillography, we were able to discriminate among persons with glaucoma and those with normal eye examinations. With refinement, pupil testing may provide a simple approach for glaucoma screening.
authors.affiliation: Glaucoma Center of Excellence, Wilmer Eye Institute, Johns Hopkins University, Baltimore, Maryland; Dana Center for Preventive Ophthalmology, Wilmer Eye Institute, Johns Hopkins University, Baltimore, Maryland; Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland. Electronic address: dchang20@jhmi.edu.
authors.forename: Dolly S
authors.initials: DS
authors.lastname: Chang
authors.forename: Karun S
authors.initials: KS
authors.lastname: Arora
authors.forename: Michael V
authors.initials: MV
authors.lastname: Boland
authors.forename: Wasu
authors.initials: W
authors.lastname: Supakontanasan
authors.forename: David S
authors.initials: DS
authors.lastname: Friedman
mesh_terms: D000368:Aged; D019540:Area Under Curve; D016022:Case-Control Studies; D003941:Diagnostic Techniques, Ophthalmological / Q000295:instrumentation*; D005260:Female; D015812:Glaucoma, Angle-Closure / Q000175:diagnosis* / Q000503:physiopathology; D005902:Glaucoma, Open-Angle / Q000175:diagnosis* / Q000503:physiopathology; D006801:Humans; D007429:Intraocular Pressure; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D011446:Prospective Studies; D011680:Pupil / Q000502:physiology*; D012372:ROC Curve; D012680:Sensitivity and Specificity; D041623:Tomography, Optical Coherence; D058609:Visual Field Tests; D014794:Visual Fields