ABSTRACT
Olfactory nerve (I) is for the sense of smell and arises from the olfactory bulb (1) at the distal end of the olfactory tract (2). Optic nerve (II) (3) is for the sense of sight. The nerves converge at the optic chiasma (4) just above and in front of the pituitary gland (5). Tumours of the gland may extend upward and impinge upon the chiasma to cause bitemporal hemianopia.
