Example markings of Bruch’s membrane opening, (BMO, red) (a). Example scleral canal area (within green perimeter), interpolated from BMO markings, and its corresponding principal axes (red, blue) (b). Scleral canal planarity was calculated as the average of distances (blue) from BMO markings (red) to BMO best-fit plane (black) (c). Example scleral canal (blue) and anterior lamina cribrosa (ALC) markings (red) used to reconstruct ALC surface and compute ALC depth (d). Heat maps of ALC depth (shallow to deep: blue to red) (e). S: Superior, N: Nasal, A: Anterior.