Luminal and stromal areas of choroid determined by binarization method of optical coherence tomographic images.

Purpose: To determine the proportion of luminal and stromal areas of normal choroids in the optical coherence tomographic (OCT) images obtained by enhanced depth imaging (EDI)-OCT.
Design: A prospective, masked, observational cross-sectional study.
Methods: setting: This study was performed at the Kagoshima University Hospital, Japan.
Study Population: One hundred and eighty right eyes of 180 healthy volunteers (106 women; mean age of 55.9 years) without ocular pathology. observational procedures: The EDI-OCT images of the posterior choroid 7500 μm from the optic disc in the horizontal plane were converted to binary images. The total cross-sectional choroidal area, luminal area, and stromal area of the choroid were measured.
Main Outcome Measures: Correlations between clinical factors and each choroidal structure and ratio of luminal/stromal areas were determined. The correlations of each choroidal structure and the age, sex, axial length (AL), and refractive errors were calculated.
Results: The mean total cross-sectional choroidal area was 1.84 mm(2) (luminal area 1.21 mm(2) and stromal area 0.63 mm(2)). Multivariate analysis (standardized partial regression coefficient) showed that age (-0.723, P < .001) was significantly correlated with the reduced area of the choroid, and the correlation was greater than that for the AL (-0.408, P < .001). The ratio of luminal/stromal area was significantly reduced in eyes with longer ALs (-0.531, P < .001), and the strength of the correlation was greater than that of age (-0.389, P < .001).
Conclusions: Although both the luminal and the stromal areas decrease with increasing age and with longer ALs, the degree of decrease and areas affected were not the same.
(Copyright © 2015 Elsevier Inc. All rights reserved.)