title: Retinal ganglion cells function measured by the PERG test in patients with ocular hypertension.
abstract: OBJECTIVE
  To assess the retinal ganglion cells function in patients with ocular hypertension (OHT).
  
  
  METHODS
  In one hundred eyes of 50 patients with ocular hypertension [mean age: 48 +/- 13 years, intraocular pressure mean: 26 +/- 3.0 mmHg; Humphrey Field Analyzer (HFA) 24-2 W-W mean deviation (MD) > -2 decibels (dB), normal optic nerve fiber layer results in scanning laser polarimetry (GDX)], PERG recordings were performed according to the modified methodology described by Parisi V et al. (Ophthalmology 2006; 113: 216-228). Main parameters measured in the PERG test were as follows: amplitude of the P50 and N95 waves, AN95/AP50 ratio as well as implicit time of P50 wave. Pattern Electroretinogram P50 implicit times were considered delayed when exceeding the limit of mean values plus 2 standard deviations (SDs) from controls. PERG amplitudes of P50, N95 waves and AN95/AP50 ratio were considered reduced when they were below the mean values minus 2 SDs from controls. Control group consisted of age, sex, and refractive error matched one hundred eyes of 50 healthy subjects with intraocular pressure mean equal to 16 +/- 4.0 mmHg.
  
  
  RESULTS
  In the OHT eyes, significant reductions of AN95-wave (p < 0.0002) and AN95/AP50 ratio (p < 0.002) were obtained in comparison to controls. The PERG test revealed the abnormalities mostly in AN95/AP50 ratio (32/100 of OHT eyes--32%). Other less frequent abnormalities were observed in amplitude of N95-wave (10/100 of OHT eyes--10%) and in amplitude of P50-wave (6/100 of OHT eyes--6%). The implicit times of P50 and N95-waves were within normal limits.
  
  
  CONCLUSIONS
  In the eyes of the OHT patients, retinal ganglion cells dysfunction is present and can be detected by the PERG test. Longer follow-up is necessary to show predictable value of the PERG examination in separation of the OHT patients with a high risk of glaucoma development.
authors.affiliation: Department of Ophthalmology, Pomeranian Medical University, Szczecin, Poland. lubinski@pro.onet.pl
authors.forename: Lubiński
authors.initials: L
authors.lastname: Wojciech
authors.forename: Gosławski
authors.initials: G
authors.lastname: Wojciech
authors.forename: Penkala
authors.initials: P
authors.lastname: Krzysztof
authors.forename: Szych
authors.initials: S
authors.lastname: Zbigniew
authors.forename: Karczewicz
authors.initials: K
authors.lastname: Danuta
mesh_terms: D000328:Adult; D004596:Electroretinography / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009798:Ocular Hypertension / Q000175:diagnosis / Q000473:pathology*; D012016:Reference Values; D012165:Retinal Ganglion Cells / Q000473:pathology* / Q000502:physiology; D012680:Sensitivity and Specificity; D014792:Visual Acuity; D058609:Visual Field Tests; D014794:Visual Fields