title: Choroidal thickness measurement in healthy Japanese subjects by three-dimensional high-penetration optical coherence tomography.
abstract: BACKGROUND
  We performed retinal and choroidal thickness mapping by three-dimensional high-penetration optical coherence tomography (OCT) and evaluated the choroidal thickness distribution throughout the macula in healthy eyes.
  
  
  METHODS
  Forty-three eyes of 43 healthy Japanese volunteers were evaluated by 1060-nm swept-source OCT. The eyes were scanned with a three-dimensional raster scanning protocol, and the mean retinal and choroidal thicknesses of the posterior sectors were obtained. The sectors were defined by the Early Treatment Diabetic Study (ETDRS) layout. These data were compared by age (23-56 years), spherical equivalent refractive error (between +0.9 D and -10.3 D), and axial length (22.9-27.6 mm).
  
  
  RESULTS
  The mean retinal and choroidal thicknesses of the ETDRS area were 284 ± 14 μm and 348 ± 63 μm respectively. The mean regional choroidal thicknesses in the nasal inner macula and nasal outer macula were significantly smaller than those in all other sectors. The mean regional choroidal thickness in most sectors showed a significant negative correlation with axial length and a significant positive correlation with refractive error. In eyes with a long axial length (>25.0 mm), the mean regional choroidal thickness of five sectors showed a significant negative correlation with age. The coefficient of variation of choroidal thickness between sectors showed a significant negative correlation with axial length, and a positive correlation with refractive error. The mean retinal thickness in each sector was not significantly correlated with the mean choroidal thickness, age, axial length, or refractive error.
  
  
  CONCLUSIONS
  The choroidal thickness map showed a distribution entirely different from the retinal thickness map. Choroidal thickness varies significantly with location, axial length, refractive error, and age. These variations should be considered when evaluating choroidal thickness.
authors.affiliation: Department of Ophthalmology, Tokyo Medical University, Ibaraki Medical Center, 3-20-1 Chuo, Ami, Inashiki, Ibaraki, 3000395, Japan.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Agawa
authors.forename: Masahiro
authors.initials: M
authors.lastname: Miura
authors.forename: Yasuhi
authors.initials: Y
authors.lastname: Ikuno
authors.forename: Shuichi
authors.initials: S
authors.lastname: Makita
authors.forename: Tapio
authors.initials: T
authors.lastname: Fabritius
authors.forename: Takuya
authors.initials: T
authors.lastname: Iwasaki
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Goto
authors.forename: Kohji
authors.initials: K
authors.lastname: Nishida
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Yasuno
mesh_terms: D000328:Adult; D002829:Choroid / Q000166:cytology*; D003930:Diabetic Retinopathy / Q000175:diagnosis* / Q000453:epidemiology; D042241:Early Diagnosis; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D021621:Imaging, Three-Dimensional; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012016:Reference Values; D015203:Reproducibility of Results; D041623:Tomography, Optical Coherence / Q000379:methods*; D055815:Young Adult