title: Spectral domain optical coherence tomography imaging of the posterior segment of the eye in the retinal dysplasia and degeneration chicken, an animal model of inherited retinal degeneration.
abstract: OBJECTIVE
  To investigate qualitative and quantitative differences in the structure of the posterior segment of the eye in 1-day post-hatch and 12-month-old retinal dysplasia and degeneration (rdd) and wild-type chickens.
  
  
  METHODS
  Retinal dysplasia and degeneration and wild-type chickens.
  
  
  METHODS
  Using a commercially available spectral domain optical coherence tomography (OCT) system, 15° horizontal line scans were performed in both eyes of 24 live birds. Qualitative differences in retinal lamination and choroidal structure were investigated, and retinal and choroidal thickness were measured.
  
  
  RESULTS
  Progressive retinal thinning with loss of outer retinal lamination and changes in the appearance of the choroid were seen in the rdd birds. Mean total retinal thickness was 202 μm (SD 7.8) and 251 μm (SD 8.8) in the rdd and wild-type chicks and 154 μm (SD 18) and 280 μm (SD 10.8) in the adult birds. Much of the difference was the result of loss of outer retinal lamination and thickness in the rdd birds. Mean choroidal thickness was 76 μm (SD 19.6) and 112 μm (SD 36.9) in the rdd and wild-type chicks and 85 μm (SD 23.7) and 228 μm (SD 44.1) in the rdd and wild-type adult birds, respectively.
  
  
  CONCLUSIONS
  Differences in retinal and choroidal structure and thickness between rdd and wild-type birds were evident on spectral domain OCT imaging at 1-day post-hatch and more marked at 1 year. Spectral domain OCT may provide a reliable end point for therapeutic intervention in this animal model of inherited retinal degeneration.
authors.affiliation: Eye Clinic, St. James's University Hospital, Leeds, UK.
authors.forename: Martin
authors.initials: M
authors.lastname: McKibbin
authors.forename: Manir
authors.initials: M
authors.lastname: Ali
authors.forename: Chris
authors.initials: C
authors.lastname: Inglehearn
authors.forename: Mike
authors.initials: M
authors.lastname: Shires
authors.forename: Kenny
authors.initials: K
authors.lastname: Boyle
authors.forename: Paul M
authors.initials: PM
authors.lastname: Hocking
mesh_terms: D000818:Animals; D002645:Chickens; D005838:Genotype; D012162:Retinal Degeneration / Q000235:genetics / Q000473:pathology / Q000662:veterinary*; D015792:Retinal Dysplasia / Q000235:genetics / Q000473:pathology / Q000662:veterinary*; D041623:Tomography, Optical Coherence / Q000662:veterinary*
keywords: choroidal structure; optical coherence tomography; retinal degeneration; retinal thickness