Size of optic disc is

Optic disc.The optic disc or optic nerve head is the point of exit for ganglion cell axons leaving the eye. Because there are no rods or cones overlying the optic disc, it corresponds to a small blind spot in each eye. The ganglion cell axons form the optic nerve after they leave the eye. It is a pink coloured, well defined veically oval area with average dimension of 1.76 mm horizontally and 1.88 mm veically. It is placed 3.4 mm nasal to the fovea. Reference: A.K.Khurana; 6th edition; Page no:263