title: [Photopic negative response of eyes with normal-tension glaucoma].
abstract: OBJECTIVE
  The purpose of this study was to investigate the behavior of the photopic negative response(PhNR) of cone-induced electroretinogram (cone ERG) in patients with normal-tension glaucoma (NTG).
  
  
  METHODS
  Cone ERGs were recorded from 30 eyes of 30 patients with NTG according to the recording conditions of the International Society for Clinical Electrophysiology of Vision protocol which is now widely used in clinics. The amplitudes and implicit times of the PhNRs were measured and compared with normal controls. I further attempted to find a correlation between the PhNR amplitude loss and the cupping/disc ratio representing a loss of the nerve fiber layer and severity of visual field defbct.
  
  
  RESULTS
  The PhNR amplitudes recorded from patients with NTG were significantly reduced compared with those from normal subjects (p < 0.05). However, the PhNR amplitude loss did not correlate with the cupping/disc ratio or the severity of visual field defect.
  
  
  CONCLUSIONS
  The Results suggested that the PhNR amplitude qualitatively reflected ganglion cell loss in patients with NTG even under recording conditions which are widely used in the clinical field.
authors.affiliation: Department of Ophthalmology, Iwate Medical University School of Medicine, 19-1 Uchimaru, Morioka 020-8505, Japan.
authors.forename: Yasutaka
authors.initials: Y
authors.lastname: Gotoh
mesh_terms: D000328:Adult; D000368:Aged; D004596:Electroretinography; D005260:Female; D005901:Glaucoma / Q000503:physiopathology*; D006801:Humans; D007429:Intraocular Pressure; D008297:Male; D008875:Middle Aged; D010775:Photic Stimulation