title: In vivo adaptive optics imaging of the temporal raphe and its relationship to the optic disc and fovea in the human retina.
abstract: OBJECTIVE
  To investigate the anatomy of the temporal raphe and its angular relationship to the optic disc and fovea in the human retina in vivo.
  
  
  METHODS
  Adaptive optics scanning laser ophthalmoscope (AOSLO) was used to image the temporal raphe in 11 young subjects. The raphe's angle relative to a horizontal line and the raphe-fovea-disc angle (angle between the raphe and the line connecting the disc and fovea center) were determined. In addition, to investigate the impact of aging on the raphe, we imaged the raphe at 9° eccentricity in 10 additional older healthy subjects and compared the raphe's anatomy between the two age groups.
  
  
  RESULTS
  The raphe's in vivo appearance was generally in agreement with major findings of ex vivo studies. The raphe angle was -1.67° ± 4.8°, with the ranges from -9° to 6°. It was related to the angle of the foveal depression relative to the disc. The raphe-fovea-disc angle was 170.3° ± 3.6°. The raphe gap, defined as the averaged distance between superior and inferior bundles, was significantly larger in the older subjects than in younger subjects (230.83 ± 113.22 μm vs. 1.93 ± 68.73 μm, P < 0.0001).
  
  
  CONCLUSIONS
  The angle of the raphe in the study was not consistent with classic raphe models. While the angle showed relatively large individual variability, there seems to be a systematic relation between the disc, fovea, and raphe. It may be useful for individualizing retinal measurement strategies with regard to perimetry.
authors.affiliation: School of Optometry, Indiana University, Bloomington, Indiana, United States.
authors.forename: Gang
authors.initials: G
authors.lastname: Huang
authors.affiliation: School of Optometry, Indiana University, Bloomington, Indiana, United States.
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Gast
authors.affiliation: School of Optometry, Indiana University, Bloomington, Indiana, United States.
authors.forename: Stephen A
authors.initials: SA
authors.lastname: Burns
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging; D005260:Female; D005584:Fovea Centralis / Q000033:anatomy & histology*; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000295:instrumentation / Q000379:methods*; D008297:Male; D008875:Middle Aged; D019721:Ophthalmoscopes; D009887:Ophthalmoscopy / Q000379:methods*; D009898:Optic Disk / Q000033:anatomy & histology*; D058609:Visual Field Tests / Q000379:methods; D055815:Young Adult
keywords: adaptive optics; foveal depression; nerve fiber layer; raphe