title: High-resolution imaging of the retinal nerve fiber layer in normal eyes using adaptive optics scanning laser ophthalmoscopy.
abstract: OBJECTIVE
  To conduct high-resolution imaging of the retinal nerve fiber layer (RNFL) in normal eyes using adaptive optics scanning laser ophthalmoscopy (AO-SLO).
  
  
  METHODS
  AO-SLO images were obtained in 20 normal eyes at multiple locations in the posterior polar area and a circular path with a 3-4-mm diameter around the optic disc. For each eye, images focused on the RNFL were recorded and a montage of AO-SLO images was created.
  
  
  RESULTS
  AO-SLO images for all eyes showed many hyperreflective bundles in the RNFL. Hyperreflective bundles above or below the fovea were seen in an arch from the temporal periphery on either side of a horizontal dividing line to the optic disc. The dark lines among the hyperreflective bundles were narrower around the optic disc compared with those in the temporal raphe. The hyperreflective bundles corresponded with the direction of the striations on SLO red-free images. The resolution and contrast of the bundles were much higher in AO-SLO images than in red-free fundus photography or SLO red-free images. The mean hyperreflective bundle width around the optic disc had a double-humped shape; the bundles at the temporal and nasal sides of the optic disc were narrower than those above and below the optic disc (P<0.001). RNFL thickness obtained by optical coherence tomography correlated with the hyperreflective bundle widths on AO-SLO (P<0.001)
  
  
  CONCLUSIONS
  AO-SLO revealed hyperreflective bundles and dark lines in the RNFL, believed to be retinal nerve fiber bundles and Müller cell septa. The widths of the nerve fiber bundles appear to be proportional to the RNFL thickness at equivalent distances from the optic disc.
authors.affiliation: Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan.
authors.forename: Kohei
authors.initials: K
authors.lastname: Takayama
authors.forename: Sotaro
authors.initials: S
authors.lastname: Ooto
authors.forename: Masanori
authors.initials: M
authors.lastname: Hangai
authors.forename: Naoko
authors.initials: N
authors.lastname: Arakawa
authors.forename: Susumu
authors.initials: S
authors.lastname: Oshima
authors.forename: Naohisa
authors.initials: N
authors.lastname: Shibata
authors.forename: Masaaki
authors.initials: M
authors.lastname: Hanebuchi
authors.forename: Takashi
authors.initials: T
authors.lastname: Inoue
authors.forename: Nagahisa
authors.initials: N
authors.lastname: Yoshimura
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D007564:Japan; D007834:Lasers; D008297:Male; D009412:Nerve Fibers / Q000648:ultrastructure*; D009887:Ophthalmoscopy / Q000379:methods*; D055351:Retinal Neurons / Q000648:ultrastructure*; D018709:Statistics, Nonparametric; D041623:Tomography, Optical Coherence