title: Variability of the normalised rim/disc area quotient estimated by laser scanning tomography. A comparison with conventional planimetry.
abstract: BACKGROUND
  The introduction of the laser scanning tomograph raises the possibility of the estimation of optic disc morphology in a less subjective and less time-consuming way than the conventional planimetry of fundus photography. The aim of the present study was to estimate the efficiency of the HRT method in a comparison of data collected in a glaucomatous patient group to planimetric data obtained in young normal volunteers.
  
  
  METHODS
  Repeated rim/disc area measurements were done in 10 glaucoma patients with a Heidelberg Retina Tomograph and in a group of five young volunteers with good vision. The intra-photographic, intra-observer examination of the planimetric method was compared to the inter-photographic assessment of the HRT technique.
  
  
  RESULTS
  The variability of the mean normalised area ratio quotient was nearly 50% less using laser scanning tomography techniques (mean rim/disc area ratio = 0.17).
  
  
  CONCLUSIONS
  The results show the superiority of HRT over the conventional planimetric technique. Furthermore, the much shorter processing time and the advantages of a computer-based databank in follow-up examination with HRT provides the hope that it could replace the rather time-consuming and subjective manual planimetric technique in the examination of glaucomatous optic nerve conditions.
authors.affiliation: Department of Ophthalmology, University of Cologne, Joseph-Stelzmann Str 9. D-50931 Cologne, Germany. borosa@web.de
authors.forename: A S
authors.initials: AS
authors.lastname: Boros
authors.forename: C P
authors.initials: CP
authors.lastname: Jonescu-Cuypers
authors.forename: K U
authors.initials: KU
authors.lastname: Bartz-Schmidt
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D003941:Diagnostic Techniques, Ophthalmological; D005260:Female; D005654:Fundus Oculi; D005902:Glaucoma, Open-Angle / Q000175:diagnosis*; D006801:Humans; D007834:Lasers; D008297:Male; D008875:Middle Aged; D009798:Ocular Hypertension / Q000175:diagnosis; D009898:Optic Disk / Q000473:pathology*; D010781:Photography; D014054:Tomography