Enhanced depth imaging (EDI) scan from spectral domain optical coherence tomography (SD OCT) with semiautomated software image segmentation of the choroid representing retinal pigment epithelium (RPE) and choroid scleral junction as the boundary for choroidal area.

<p><i>Definitions of Areas on EDI-OCT</i>: <b><i>Subfoveal choroidal thickness (SFCT)</i>:</b> Distance between the outer border of hyperreflective retinal pigment epithelium (RPE) and the outer border of the choroid beneath the centre of the fovea. <b><i>Luminal Area (LA)</i>:</b> Area of dark pixels in the choroid seen on binarised EDI-OCT images was defined as LA or vascular area. This area corresponds to the vascular area of the choroid when compared to original EDI-OCT images. <b><i>Stromal Area (SA)</i>:</b> Area of light pixels in the choroid seen on binarised EDI-OCT images was defined as SA or interstitial area. This area corresponds to the interstitial areas of the choroid when compared to original EDI-OCT images. <b><i>Choroidal Vascularity Index (CVI)</i>:</b> The ratio or proportion of the LA within the circumscribed subfoveal choroidal area.