Session Title: Free Paper Session 12: Imaging I
Session Date/Time: Friday 08/09/2017 | 14:30-16:00
Paper Time: 15:24
Venue: Room 111
First Author: : Y.Matsui JAPAN
Co Author(s): : M. Mizouchi S. Tanaka N. Kobayashi E. Uchiyama M. Kondo
Recent advances in the spectral-domain optical coherence tomography (SD-OCT) have allowed clinicians to obtain detailed images of multiple reflective bands in the outer retina. However, it is still difficult to separate two of the hyperreflective bands which correspond to the retinal pigment epithelium (RPE) and Bruch’s membrane (BM) in normal retinas because the distance between them is very close. In this study, we estimated the thickness of the RPE and the origin of that reflection measured by an ultrahigh resolution SD-OCT (UHR-SD-OCT).
Twelve eyes of 12 healthy volunteers (9 men and 3 women; mean age, 28.5 years) were studied. The mean axial length was 23.8 mm. Vertical scans through the fovea were obtained with the UHR-SD-OCT (Bi-µ: Kowa Company, Tokyo, Japan). The reflectivity of the A-scans was evaluated quantitatively by measuring a longitudinal reflectivity profile (LRP) at seven points in the macula. The thickness of the peak in RPE and the distance between the peaks of the RPE and BM reflection were measured with a Gaussian fitting method.
The LRP of the RPE was composed of several highly reflective bands. The thickness of the higher reflection band of the RPE was 5.12-5.73 μm, and was thinnest at the central fovea. The distance between the peaks of RPE and BM reflection was 8.46-11.7 μm.
The reflection derived from RPE is mainly located in the upper part in RPE. Our findings combined with past histological reports suggest that the highly reflective materials in the RPE probably correspond to the melanin granules.