title: Comparisons of choroidal thickness of normal eyes obtained by two different spectral-domain OCT instruments and one swept-source OCT instrument.
abstract: OBJECTIVE
  We compared the subfoveal choroidal thickness (SFCT) measured on the images obtained by two spectral-domain optical coherence tomographic (SD-OCT) instruments and one swept-source OCT (SS-OCT) instrument.
  
  
  METHODS
  A cross-sectional, prospective noninterventional study was done in which SFCT was measured in the images obtained by two SD-OCT instruments; Heidelberg Spectralis-OCT (Spectralis-SD-OCT) and Topcon 3D OCT-1000 Mark II (Topcon-SD-OCT). Images also were obtained with SS-OCT Atlantis DRI OCT-1 (DRI-SS-OCT). After manual segmentation, the measurements were made using the calipers embedded in each instrument. The intrarater, interrater, and intermachine agreements were assessed.
  
  
  RESULTS
  We studied 35 subjects. The intrarater correlation coefficient (95% confidence interval) was 0.994 (0.988-0.994) for Spectralis-SD-OCT, 0.996 (0.993-0.998) for Topcon-SD-OCT, and 0.997 (0.991-0.998) for DRI-SS-OCT (P < 0.001). The interrater correlation coefficient was 0.995 (0.991-0.998) for Spectralis-SD-OCT, 0.995 (0.990-0.998) for Topcon-SD-OCT, and 0.996 (0.992-0.998) for DRI-SS-OCT (P < 0.001). The average SFCT was 273.2 μm with Spectralis-SD-OCT, 269.1 μm with the Topcon-SD-OCT, and 280.5 μm with DRI-SS-OCT. The intermachine correlation coefficient was 0.982 (0.964-0.991) for Spectralis-SD-OCT versus Topcon-SD-OCT, 0.907 (0.815-0.953) for Topcon-SD-OCT versus DRI-SS-OCT, and 0.911 (0.832-0.954) for DRI-SS-OCT versus Spectralis-SD-OCT (P < 0.001). The SFCT measured with DRI-SS-OCT was significantly thicker than that with Topcon-SD-OCT, with a mean difference of 11.41 ± 30.27 μm (P = 0.032).
  
  
  CONCLUSIONS
  In normal adult eyes, there was good reproducibility and repeatability of SFCT measurements obtained by the SD-OCT and SS-OCT instruments. However, the choroid measured with DRI-SS-OCT was thicker than that measured with both SD-OCT instruments, and, thus, the choroidal thickness should not be compared between the SD-OCT and SS-OCT instruments. (www.umin.ac.jp/ctr number, UMIN000011259.).
authors.affiliation: Department of Ophthalmology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan.
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Matsuo
authors.forename: Taiji
authors.initials: T
authors.lastname: Sakamoto
authors.forename: Takehiro
authors.initials: T
authors.lastname: Yamashita
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Tomita
authors.forename: Makoto
authors.initials: M
authors.lastname: Shirasawa
authors.forename: Hiroto
authors.initials: H
authors.lastname: Terasaki
mesh_terms: D000328:Adult; D002829:Choroid / Q000033:anatomy & histology*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D009929:Organ Size; D011446:Prospective Studies; D012016:Reference Values; D015203:Reproducibility of Results; D041623:Tomography, Optical Coherence / Q000295:instrumentation*; D014792:Visual Acuity / Q000502:physiology; D055815:Young Adult
keywords: choroid; diabetic retinopathy; penetration; retinal pigment epithelium