2.2 | Optical coherence tomography technique
Scans were obtained by a trained OCT technician using an SD-OCT device
(Spectralis OCT®; Heidelberg Engineering, Heidelberg, Germany) without
pupil dilatation. All EDI-OCT measurements were performed at specific
times (between 09:00 and 12:00 a.m.) in order to avoid the effect of
diurnal variation. A 9 mm high-resolution line scan passing the
horizontal fovea was recorded. This datum was measured using the
software (Heidelberg Eye Explorer®, Version 1.7.0.0; Heidelberg
Engineering) installed on the device. Thicknesses of choroid at three
points and GCC layers (RNFL at five points, GCL and IPL) were obtained
manually by the same experienced ophthalmologist using EDI-OCT (Figure
1,2). Choroidal thickness was measured manually at the foveal center and
within the nasal and temporal quadrants at 500
µm intervals from the foveal
center Three measurement values taken from at every point of measurement
and the average of this measurements taken into statistical analysis.
2.3 | Statistical
Analysis
SPSS®, Version 21, software (Chicago, IL, USA) was used for statistical
analyses. Descriptive and comparative analysis was employed to
characterize the study population. The variables were investigated using
visual and analytical methods to determine normality. The Student’st -test and Mann–Whitney U test were used to compare these
parameters between groups.