title: The multi-channel VEP topographies in patients with late-stage glaucoma.
abstract: OBJECTIVE
  To study the clinical application of multi-channel VEP topographies in patients with late-stage glaucoma.
  
  
  METHODS
  The multi-channel checkerboard reversal VEP waves of 25 normal persons and 15 patients with late-stage glaucoma were recorded and analyzed, All patients were examined using Humphrey Field Analyzer. The VEP topographies of multi-channel VEP waves were shown by computer processing system.
  
  
  RESULTS
  In normal subjects, the topographies showed symmetric distribution to full-field pattern stimulation. In all patients with late-stage glaucoma, even whose visual field was severely damaged, multi-channel VEP could be recorded, All channels showed simple 'NPN' wave form, N1, N2 waves were not conspicuous, even both were lost, all channels showed the reduced amplitudes of P1 waves, and longer latency. The multi-channel VEP topographies showed irregular distribution, Some showed amplitude asymmetry, other limited or widespread, lateralized.
  
  
  CONCLUSIONS
  Despite the severely damaged visual field, the patients with late-stage glaucoma showed special multi-channel VEPs topographies, Multi-channel VEP topographies should be useful in following up patients suffering from late-stage glaucoma and studying visual processing in human brain.
authors.affiliation: Zhongshan Ophthalmic Center, Sun Yat-sen University of Medical Sciences, Guangzhou 510060, China.
authors.forename: C
authors.initials: C
authors.lastname: Hu
authors.forename: L
authors.initials: L
authors.lastname: Wu
authors.forename: D Z
authors.initials: DZ
authors.lastname: Wu
authors.forename: F
authors.initials: F
authors.lastname: Jiang
mesh_terms: D000293:Adolescent; D000328:Adult; D001931:Brain Mapping; D003118:Color Perception / Q000502:physiology; D005074:Evoked Potentials, Visual; D005260:Female; D005901:Glaucoma / Q000175:diagnosis / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010364:Pattern Recognition, Visual / Q000502:physiology*; D014793:Visual Cortex / Q000503:physiopathology*; D058609:Visual Field Tests; D014794:Visual Fields