Characteristics of (a) normal macula (NM): a smooth depression shows at the center (fovea), (b) macular edema (ME) : retinal thickening and liquid accumulation appears as black blobs around the fovea, (c) macular hole (MH): a full-thickness hole (FH, 1st row) or pseudo hole (PH, 2nd row) formation at the fovea; for PH, the hole formation does not reach the outer most retinal layer (retinal pigment epitherium, RPE), (d) age-related macular degeneration (AMD): irregular contours usually extrude in dome shapes appear at the bottom layer (RPE) of the retina.