title: Profile and Determinants of Retinal Optical Intensity in Normal Eyes with Spectral Domain Optical Coherence Tomography.
abstract: OBJECTIVE
  To investigate the profile and determinants of retinal optical intensity in normal subjects using 3D spectral domain optical coherence tomography (SD OCT).
  
  
  METHODS
  A total of 231 eyes from 231 healthy subjects ranging in age from 18 to 80 years were included and underwent a 3D OCT scan. Forty-four eyes were randomly chosen to be scanned by two operators for reproducibility analysis. Distribution of optical intensity of each layer and regions specified by the Early Treatment of Diabetic Retinopathy Study (ETDRS) were investigated by analyzing the OCT raw data with our automatic graph-based algorithm. Univariate and multivariate analyses were performed between retinal optical intensity and sex, age, height, weight, spherical equivalent (SE), axial length, image quality, disc area and rim/disc area ratio (R/D area ratio).
  
  
  RESULTS
  For optical intensity measurements, the intraclass correlation coefficient of each layer ranged from 0.815 to 0.941, indicating good reproducibility. Optical intensity was lowest in the central area of retinal nerve fiber layer, ganglion cell layer, inner plexiform layer, inner nuclear layer, outer plexiform layer and photoreceptor layer, except for the retinal pigment epithelium (RPE). Optical intensity was positively correlated with image quality in all retinal layers (0.553<β<0.851, p<0.01), and negatively correlated with age in most retinal layers (-0.362<β<-0.179, p<0.01), except for the RPE (β = 0.456, p<0.01), outer nuclear layer and photoreceptor layer (p>0.05). There was no relationship between retinal optical intensity and sex, height, weight, SE, axial length, disc area and R/D area ratio.
  
  
  CONCLUSIONS
  There was a specific pattern of distribution of retinal optical intensity in different regions. The optical intensity was affected by image quality and age. Image quality can be used as a reference for normalization. The effect of age needs to be taken into consideration when using OCT for diagnosis.
authors: Joint Shantou International Eye Center, Shantou University and the Chinese University of Hong Kong, Shantou, China.
authors: Binyao
authors: B
authors: Chen
authors: School of Electronics and Information Engineering, Soochow University, Suzhou, China.
authors: Enting
authors: E
authors: Gao
authors: Joint Shantou International Eye Center, Shantou University and the Chinese University of Hong Kong, Shantou, China.
authors: Haoyu
authors: H
authors: Chen
authors: Joint Shantou International Eye Center, Shantou University and the Chinese University of Hong Kong, Shantou, China.
authors: Jianling
authors: J
authors: Yang
authors: School of Electronics and Information Engineering, Soochow University, Suzhou, China.
authors: Fei
authors: F
authors: Shi
authors: Joint Shantou International Eye Center, Shantou University and the Chinese University of Hong Kong, Shantou, China.
authors: Ce
authors: C
authors: Zheng
authors: School of Electronics and Information Engineering, Soochow University, Suzhou, China.
authors: Weifang
authors: W
authors: Zhu
authors: School of Electronics and Information Engineering, Soochow University, Suzhou, China.
authors: Dehui
authors: D
authors: Xiang
authors: School of Electronics and Information Engineering, Soochow University, Suzhou, China.
authors: Xinjian
authors: X
authors: Chen
authors: Joint Shantou International Eye Center, Shantou University and the Chinese University of Hong Kong, Shantou, China.
authors: Mingzhi
authors: M
authors: Zhang
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D002681:China; D003930:Diabetic Retinopathy / Q000517:prevention & control; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D015588:Observer Variation; D012044:Regression Analysis; D015203:Reproducibility of Results; D012160:Retina / Q000473:pathology* / Q000502:physiology*; D012984:Software; D013053:Spectrophotometry; D041623:Tomography, Optical Coherence; D055815:Young Adult