Abstract
Purpose: :
To demonstrate the choroidal thickness mapping with Early Treatment Diabetic Retinopathy Study (ETDRS) layout by using high-penetration optical coherence tomography (OCT). To evaluate the three-dimensional choroidal thickness distribution in healthy eyes.
Methods: :
Forty-three eyes of 43 healthy Japanese volunteers were evaluated by using 1060-nm swept source OCT. The mean regional choroidal thickness (ChT) was measured with the ETDRS layout by using three-dimensional raster scanning. The mean ChT at each sector was compared with age (23-56 y), spherical equivalent refractive error (between +0.9D and -10.3 D), and axial length (22.9-27.6 mm).
Results: :
The mean ChT of the whole ETDRS area was 348 µm (SD 63 µm) (range, 217-544 µm). The mean regional ChT at the nasal inner macula and nasal outer macula were significantly smaller than those at all other sectors (P < 0.05). The mean regional ChT at each sector showed significant negative correlation with axial length (P < 0.05, R2: 0.10 - 0.18) and positive correlation with refractive error (P < 0.05, R2: 0.10- 0.18), except superior outer macula (P = 0.16 for axial length, P = 0.21 for refractive error). Mean ChT at each sector showed no significant correlation with age, while in the eyes with long axial length (>25.0 mm), mean regional ChT at five sectors (central subfield, nasal inner macula, superior inner macula, temporal inner macula, and superior outer macula) showed significant negative correlation with age (P < 0.05). Coefficient of variation among the sectors showed significant positive correlation with axial length (P = 0.04, R2 = 0.10) and negative correlation with refractive error (P = 0.01, R2 = 0.16).
Conclusions: :
ChT varied significantly with location, axial length, refractive error, and age. These variations should be considered when evaluating ChT.
Keywords: imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • choroid • imaging/image analysis: clinical