title: Change in optic disc topography associated with diurnal variation in intraocular pressure.
abstract: OBJECTIVE
  A case demonstrating significant changes in optic disc topography from variation in intraocular pressure (IOP) is demonstrated.
  
  
  METHODS
  Within a single 24-hour period, confocal scanning laser ophthalmoscopic images were obtained in the left eye of a patient during an IOP peak (60 mmHg) and during an IOP trough (18 mmHg).
  
  
  RESULTS
  During an IOP trough, paired t tests showed significant reduction in cup area, cup volume, mean cup depth, and maximum cup depth, and a significant increase in rim area and cup-to-disc (CD) ratio.
  
  
  CONCLUSIONS
  Under certain conditions, optic disc topography may be affected by diurnal variations in IOP.
authors.affiliation: Glaucoma Center and Research Laboratory, University of California at San Diego, La Jolla 92093-0946, USA.
authors.forename: B L
authors.initials: BL
authors.lastname: Lee
authors.forename: L
authors.initials: L
authors.lastname: Zangwill
authors.forename: R N
authors.initials: RN
authors.lastname: Weinreb
mesh_terms: D000328:Adult; D002908:Chronic Disease; D002940:Circadian Rhythm; D005260:Female; D005902:Glaucoma, Open-Angle / Q000473:pathology* / Q000601:surgery; D006801:Humans; D007429:Intraocular Pressure; D053685:Laser Therapy; D009887:Ophthalmoscopy; D009898:Optic Disk / Q000473:pathology*; D014130:Trabeculectomy