Retina is the innermost nervous coat of eyeball, and it contains some special photo receptor structures called “rods and cones.”
Optic nerve is formed by the axons of ganglionic cells, which leaves the eye through optic disk. Optic nerves transmit the sensations from the each eye to the brain. Damage to the retina or optic nerve of one eye results in monocular blindness.
Thus, the blank can be filled with monocular blindness.