title: Relationship between pattern electroretinogram, standard automated perimetry, and optic nerve structural assessments.
abstract: OBJECTIVE
  To examine the relationship between retinal ganglion cell function measured using pattern electroretinogram optimized for glaucoma screening (PERGLA), retinal nerve fiber layer (RNFL) thickness, and optic nerve head topography.
  
  
  METHODS
  Twenty-nine normal, 28 glaucoma, and 37 glaucoma suspect volunteers were enrolled. All participants were age similar. One randomly selected eye underwent complete eye examination, standard automated perimetry (SAP), scanning laser polarimetry with enhanced corneal compensation (GDxECC), optical coherence tomography, Heidelberg retina tomograph (HRT), and PERGLA measurements. PERGLA amplitude (microV) was converted to dB for comparison with SAP mean deviation (MD) and pattern SD. The correlation between PERGLA amplitude in dB and the average of sensitivity values for 16 central test locations of SAP were calculated. Analysis of variance, Pearson and Spearman rank correlations, coefficient of variation, and intraclass correlation coefficients were calculated.
  
  
  RESULTS
  PERGLA amplitude in glaucomatous eyes was significantly lower than normal eyes (0.47+/-0.20 vs. 0.70+/-0.28 microV, P<0.001) but not glaucoma suspects (0.54+/-0.21 microV, P=0.84). PERGLA amplitude was inversely correlated with age (r=-0.31, P=0.002). PERGLA amplitude (in dB) was associated with the sensitivity values of the SAP central 16 test locations (r=0.40, P<0001) across the entire cohort, GDxECC superior RNFL thickness (r=0.38, P<0.001), and HRT Moorfields regression analysis classification (rho=-0.34, P=0.001). The coefficient of variation and intraclass correlation coefficients were 14.5% and 0.89 for PERGLA amplitude, 2.4% and 0.98 for optical coherence tomography average RNFL, 2.2% and 0.97 for GDxECC temporal superior nasal inferior temporal average, and 6.3% and 0.94 for HRT rim area.
  
  
  CONCLUSIONS
  Retinal ganglion cell function measured using PERGLA is reduced in glaucoma and demonstrates modest correlations with central SAP sensitivity values and structural measures of optic nerve topography and RNFL thickness.
authors.affiliation: Department of Ophthalmology, University of Miami Miller School of Medicine, Bascom Palmer Eye Institute, Palm Beach Gardens, FL 33418, USA. msehi@med.miami.edu
authors.forename: Mitra
authors.initials: M
authors.lastname: Sehi
authors.forename: Mariana
authors.initials: M
authors.lastname: Pinzon-Plazas
authors.forename: William J
authors.initials: WJ
authors.lastname: Feuer
authors.forename: David S
authors.initials: DS
authors.lastname: Greenfield
mesh_terms: D000368:Aged; D001331:Automation; D015331:Cohort Studies; D004596:Electroretinography / Q000379:methods*; D005260:Female; D005901:Glaucoma / Q000175:diagnosis / Q000473:pathology* / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009412:Nerve Fibers / Q000473:pathology; D009798:Ocular Hypertension / Q000175:diagnosis / Q000473:pathology* / Q000503:physiopathology*; D009900:Optic Nerve / Q000473:pathology*; D012160:Retina / Q000473:pathology; D012165:Retinal Ganglion Cells; D057109:Scanning Laser Polarimetry; D012680:Sensitivity and Specificity; D041623:Tomography, Optical Coherence; D058609:Visual Field Tests