title: Pressure-dependent changes of the optic disk in primary open-angle glaucoma.
abstract: OBJECTIVE
  This study was performed to differentiate glaucomatous changes of the optic disk that may be caused by increased intraocular pressure from those that may be pressure independent.
  
  
  METHODS
  For 357 patients with primary open-angle glaucoma, the optic disk was morphometrically analyzed, and the intraocular pressure was measured in 24-hour profiles.
  
  
  RESULTS
  By performing an intraindividual bilateral comparison, the differences in the maximal intraocular pressure values of the right eye minus the left eye of the same individual were significantly correlated with the differences in neuroretinal rim area and mean perimetric defect of the right eye minus the left eye. No significant correlations were found for the parapapillary atrophy.
  
  
  CONCLUSIONS
  The results indicate that the eye with the higher pressure compared with the fellow eye with the lower pressure showed neither a significantly larger nor smaller parapapillary atrophy, which suggests that the papapapillary atrophy, compared with the neuroretinal rim area and the visual field defect, is less dependent or almost independent of an increased intraocular pressure.
authors.affiliation: Department of Ophthalmology, University Erlangen-Nürnberg, Germany.
authors.forename: J B
authors.initials: JB
authors.lastname: Jonas
authors.forename: K I
authors.initials: KI
authors.lastname: Papastathopoulos
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001284:Atrophy; D005260:Female; D005654:Fundus Oculi; D005902:Glaucoma, Open-Angle / Q000503:physiopathology*; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D009898:Optic Disk / Q000473:pathology / Q000503:physiopathology*; D014794:Visual Fields