(a)
(b)
Figure 1: (a) A photographic image of the optic nerve head, divided into 24 regular sectors around its centroid, used by the Laguna ONhE program (3 nasal and 15 temporal). (b) The relative percentage amounts of hemoglobin in the optic nerve head tissue compared to that of the vessels, which is taken as the reference value (100%) and the estimated position of the cup.