title: [Comparison of optic nerve head measurements obtained with the slit lamp and with CSLO].
abstract: OBJECTIVE
  To evaluate the accuracy of disk size and cup/disk ratio (C/D) estimation by measuring the vertical diameter and cup/disk ratio at the slit lamp.
  
  
  METHODS
  Two hundred and thirty eight eyes of 185 people, 82 glaucomas and 156 normal subjects were included. All underwent slit lamp examination, tonometry, optic nerve photographs, scanning laser tomography (HRT) and standard perimetry (Humphrey). Correlation between slit lamp measurements (vertical diameter and C/D ratio) and HRT parameters was evaluated.
  
  
  RESULTS
  There is a significant correlation between the disk diameter measured at the slit lamp and the disk area measured with HRT (Pearson Test, r: 0.52, p<0.001). Additionally, there is significant correlation between the semi-quantitative estimation of C/D ratio at the slit lamp and the C/D area ratio from the HRT (r: 0.83, p<0.001).
  
  
  CONCLUSIONS
  Measuring the vertical diameter and the C/D ratio at the slit lamp is a useful method for estimating the real disk area and C/D ratio. It is highly recommended that disk size be estimated when attempting to interpret clinical findings in the optic nerve head.
authors.affiliation: IOBA, Universidad de Valladolid, Spain.
authors.forename: M E
authors.initials: ME
authors.lastname: Ayala Fuentes
authors.forename: M T
authors.initials: MT
authors.lastname: Andrada Márquez
authors.forename: A
authors.initials: A
authors.lastname: Antón
mesh_terms: D000886:Anthropometry; D005260:Female; D005901:Glaucoma / Q000473:pathology; D006801:Humans; D008297:Male; D018613:Microscopy, Confocal; D008875:Middle Aged; D009900:Optic Nerve / Q000033:anatomy & histology* / Q000473:pathology; D015203:Reproducibility of Results