title: Relation of optical coherence tomography to microanatomy in normal and rd chickens.
abstract: OBJECTIVE
  To elucidate the relation between optical coherence tomography (OCT) scans and retinal histology in normal and retinal degeneration (rd) chickens.
  
  
  METHODS
  Retinas from adult normal and rd chickens were examined in vivo with OCT at 850 nm and compared quantitatively with stained cryosections of unfixed retinas from the same locations.
  
  
  RESULTS
  The nerve fiber layer (NFL) and inner plexiform layer (IPL) show homogeneous backscatter throughout their thicknesses. NFL reflectivity is approximately 0.6 log units higher than that of the IPL. The inner nuclear layer shows a low reflectivity; the properties of reflections from ganglion cell and outer nuclear layers are indeterminate. The outer retina and choroid form a large reflective complex. Photoreceptor inner segments produce the highest of these reflections in normal chicken retinas, approximately 1.5 log units higher than that of the IPL. The retinal pigment epithelium also has a relatively large backscatter coefficient and is the dominant reflector in rd retinas that lack photoreceptors. Choroidal pigment produces an intermediate level of backscatter and is the largest attenuator of signal at 850 nm.
  
  
  CONCLUSIONS
  Quantified OCT signals have a predictable relationship to histology and pathology in chicken retinas. The results from rd retinas represent a first step toward in vivo quantitation of retinal structure in retinal degenerative disease.
authors.affiliation: Scheie Eye Institute, Department of Ophthalmology, University of Pennsylvania, Philadelphia 19104, USA.
authors.forename: Y
authors.initials: Y
authors.lastname: Huang
authors.forename: A V
authors.initials: AV
authors.lastname: Cideciyan
authors.forename: G I
authors.initials: GI
authors.lastname: Papastergiou
authors.forename: E
authors.initials: E
authors.lastname: Banin
authors.forename: S L
authors.initials: SL
authors.lastname: Semple-Rowland
authors.forename: A H
authors.initials: AH
authors.lastname: Milam
authors.forename: S G
authors.initials: SG
authors.lastname: Jacobson
mesh_terms: D000818:Animals; D002645:Chickens; D002829:Choroid / Q000473:pathology; D007091:Image Processing, Computer-Assisted; D009412:Nerve Fibers / Q000473:pathology; D011201:Poultry Diseases / Q000235:genetics / Q000473:pathology*; D012160:Retina / Q000033:anatomy & histology / Q000473:pathology*; D012162:Retinal Degeneration / Q000235:genetics / Q000473:pathology / Q000662:veterinary*; D012165:Retinal Ganglion Cells / Q000473:pathology; D014054:Tomography / Q000379:methods*