title: Retinal thickness and volume measured with enhanced depth imaging optical coherence tomography.
abstract: OBJECTIVE
  To evaluate the retinal thickness and volume measured with the enhanced depth imaging (EDI) method compared with those measured with the conventional method using spectral-domain optical coherence tomography (OCT).
  
  
  METHODS
  Retrospective, observational, case-control study.
  
  
  METHODS
  Clinical records of 20 healthy subjects and those of 35 patients with chorioretinopathy (central serous chorioretinopathy, polypoidal choroidal vasculopathy, Vogt-Koyanagi-Harada disease, and reticular pseudodrusen) were analyzed retrospectively. All subjects underwent spectral-domain OCT using both the conventional and the EDI OCT raster scan protocols. The raster scan was composed of 31 B-scans that were 9.0 mm in length and 240 μm apart. Retinal thickness and volume of 9 Early Treatment Diabetic Retinopathy Study subfields were investigated. Intraclass correlation coefficients, Bland-Altman plots, and Wilcoxon signed-rank test results were used for the analysis.
  
  
  RESULTS
  Sixty-five eyes of 35 patients with chorioretinal diseases and 40 eyes of 20 normal healthy subjects were evaluated. The automatically measured retinal thickness and volume of 9 Early Treatment Diabetic Retinopathy Study subfields with conventional and EDI raster scan showed an intraclass correlation coefficient of 0.861 to 0.995 and 0.873 to 0.995, respectively. The 95% limits of agreement between the 2 protocols in the measurement of central subfield were -14.52 to 12.88 μm in retinal thickness and -0.014 to 0.013 mm³ in retinal volume. The differences of segmentation error rate between the 2 protocols were statistically insignificant (P > .05), except in eyes with reticular pseudodrusen in the subgroup analysis (P = .006). No significant differences were observed in measured values between healthy eyes and unaffected fellow eyes.
  
  
  CONCLUSIONS
  The EDI OCT raster scan showed high agreement with conventional OCT in the measurement of retinal thickness and volume and could be used to evaluate both the retina and choroid in normal eyes and in eyes with some forms of chorioretinal disorder.
authors.affiliation: Department of Ophthalmology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea.
authors.forename: Sung Yong
authors.initials: SY
authors.lastname: Park
authors.affiliation: Department of Ophthalmology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea.
authors.forename: Sung Min
authors.initials: SM
authors.lastname: Kim
authors.affiliation: Department of Family Medicine, Samsung Medical Center, and Center for Clinical Research, Samsung Biomedical Research Institute, Sungkyunkwan University School of Medicine, Seoul, South Korea.
authors.forename: Yun-Mi
authors.initials: YM
authors.lastname: Song
authors.affiliation: Department of Epidemiology and Institute of Environment and Health, School of Public Health, Seoul National University, Seoul, South Korea; Genomic Medicine Institute, Medical Research Center, Seoul National University, Seoul, South Korea.
authors.forename: Joohon
authors.initials: J
authors.lastname: Sung
authors.affiliation: Department of Ophthalmology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea. Electronic address: oculus@naver.com.
authors.forename: Don-Il
authors.initials: DI
authors.lastname: Ham
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D056833:Central Serous Chorioretinopathy / Q000175:diagnosis*; D015862:Choroid Diseases / Q000175:diagnosis*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009929:Organ Size; D011127:Polyps / Q000175:diagnosis*; D015203:Reproducibility of Results; D012160:Retina / Q000473:pathology*; D015593:Retinal Drusen / Q000175:diagnosis*; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D041623:Tomography, Optical Coherence / Q000379:methods*; D014607:Uveomeningoencephalitic Syndrome / Q000175:diagnosis*