(a) A typical PFO/DOFA map of a human ONH. (b) A typical SHG image of the same ONH. PFO/DOFA maps were overlaid and aligned with SHG images to allow identification of the scleral canal margin in PFO/DOFA maps. (c) The ONH was subdivided into: the LC, terminating at the edge of the scleral canal; an insertion region, defined as an annular ring extending 150 µm from the scleral canal margin; and a peripapillary scleral region, defined as an annular ring extending from 150 to 1000 µm from the scleral canal margin. (d) The LC was subdivided into 12 regions for analysis. S, superior; N, nasal; I, inferior; T, temporal.