title: Structure-function relationship among three types of spectral-domain optical coherent tomography instruments in measuring parapapillary retinal nerve fibre layer thickness.
abstract: OBJECTIVE
  To compare the relationships of parapapillary retinal nerve fibre layer (RNFL) thickness among three spectral-domain optical coherence tomography (SD-OCT) instruments with visual field sensitivity (VFS).
  
  
  METHODS
  One hundred and thirteen eyes of 113 Japanese subjects with glaucoma (mean deviation in standard automated perimetry = -8.9 ± 6.7 dB) were imaged by Cirrus, RTVue and 3D OCT. The average hemi-superior and hemi-inferior RNFL thicknesses were obtained. In addition, the structure-function relationship using two retinotopic maps that consisted of six or nine sectors was also evaluated. Decibel (dB) scale and 1/Lamert (1/L) were used to express VFS. RNFL thickness correlation with corresponding VFS in visual field sectors was compared among the three instruments. Background RNFL thickness (non-neuronal tissue) for each instrument was estimated using a linear regression model at 1/L = 0.
  
  
  RESULTS
  The correlation between the average hemi-superior and hemi-inferior RNFL thickness in the three SD-OCT instruments with corresponding VFS was similar. In the analysis of retinotopic maps, 3D OCT showed a higher correlation in superotemporal sectors than RTVue, whereas RTVue had a stronger relationship in the nasal sector than Cirrus. The background RNFL thickness extrapolated was approximately 60% that of normal eyes in all the instruments.
  
  
  CONCLUSIONS
  The three SD-OCT showed similar overall correspondence with VFS with a partially discordant retinotopic relationship. RNFL measured with any SD-OCT devices likely contains non-neuronal tissue, comprising 60% of its thickness.
authors.affiliation: Division of Ophthalmology, Department of Surgery, Kobe University Graduate School of Medicine, Kobe, Japan. kanaaki@med.kobe-u.ac.jp
authors.forename: Akiyasu
authors.initials: A
authors.lastname: Kanamori
authors.forename: Makoto
authors.initials: M
authors.lastname: Nakamura
authors.forename: Mari
authors.initials: M
authors.lastname: Tomioka
authors.forename: Yuki
authors.initials: Y
authors.lastname: Kawaka
authors.forename: Yuko
authors.initials: Y
authors.lastname: Yamada
authors.forename: Akira
authors.initials: A
authors.lastname: Negi
mesh_terms: D000328:Adult; D003430:Cross-Sectional Studies; D005260:Female; D005902:Glaucoma, Open-Angle / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009412:Nerve Fibers / Q000473:pathology*; D009898:Optic Disk / Q000473:pathology*; D009901:Optic Nerve Diseases / Q000503:physiopathology; D015203:Reproducibility of Results; D012165:Retinal Ganglion Cells / Q000473:pathology*; D041623:Tomography, Optical Coherence / Q000295:instrumentation*; D014786:Vision Disorders / Q000503:physiopathology*; D014792:Visual Acuity / Q000502:physiology; D058609:Visual Field Tests; D014794:Visual Fields / Q000502:physiology*; D055815:Young Adult