title: Choroidal thickness profiles in retinitis pigmentosa.
abstract: BACKGROUND
  Little quantitative information exists regarding the effect that retinitis pigmentosa (RP) has on the choroid. The aim of this study was to determine choroidal thickness profiles in patients with RP.
  
  
  METHODS
  Prospective.
  
  
  METHODS
  Forty-two RP and 22 control subjects participated in the study. RP patients had mild to severe disease, with a visual acuity range of logMAR 0.1 to no light perception.
  
  
  METHODS
  Images of the retina and choroid were obtained using the enhanced depth-imaging method and optical coherence tomography (OCT). Choroidal thickness measures were determined via manual segmentation of the OCT image.
  
  
  METHODS
  The thickness profiles of the normal and RP groups were compared. The associations between choroidal thickness, visual acuity and duration of RP were determined.
  
  
  RESULTS
  The choroid was thickest in the control eyes at the subfoveal location (336.60 ± 70.42 μm), and the thickness gradually decreased towards the peripheral retina (temporal 8° = 295.55 ± 60.52 μm; nasal 8° = 251.68 ± 49.93 μm). In RP, the mean thickness was also greater at the fovea (215.60 ± 94.91 μm) than the temporal (191.66 ± 72.42 μm) and nasal (149.91 ± 57.42 μm) retina, but all values were significantly lower than those of the controls (P ≤ 0.001). Subfoveal choroidal thickness was significantly correlated with visual acuity (r = -0.46, P < 0.001) and duration of disease (r = -0.4, P = 0.001).
  
  
  CONCLUSIONS
  Patients with RP have a thinner choroid than controls. Patients with poorer visual acuity or longer duration of symptoms tended to have thinner choroids. Knowledge of choroidal thickness profile in RP is important for the field of restorative vision research and the development of suprachoroidal retinal prostheses.
authors.affiliation: Macular Research Unit, Centre for Eye Research Australia, University of Melbourne, Royal Victorian Eye and Ear Hospital, East Melbourne, Victoria, Australia.
authors.forename: Lauren N
authors.initials: LN
authors.lastname: Ayton
authors.forename: Robyn H
authors.initials: RH
authors.lastname: Guymer
authors.forename: Chi D
authors.initials: CD
authors.lastname: Luu
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002829:Choroid / Q000473:pathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009929:Organ Size; D011446:Prospective Studies; D012174:Retinitis Pigmentosa / Q000503:physiopathology*; D041623:Tomography, Optical Coherence; D014786:Vision Disorders / Q000503:physiopathology*; D014792:Visual Acuity / Q000502:physiology