Optic Nerve Flashcards
1
Q
Why is optic nerve not a true peripheral nerve?
A
It is actually a tract of brain for it develops as an outgrowth of diencephalic during embryonic life
2
Q
Special features hence?
A
2nd order sensory neurons
Myelinated by oligodendrocytes
Surrounded by meninges
Fibres cannot regenerate if cut/damaged.
3
Q
Functional component?
A
Special somatic afferent fibres
4
Q
Course
A
Ganglion cells of retina- optic nerve- middle cranial fossa through optic canal- optic chiasma- optic tracts- lateral geniculate body- optic radiation- visual cortex (calcarine sulcus of occipital lobe)
5
Q
So therefore it’s divided into three parts which are?
A
Intraorbital
Canalicular
Cranial
6
Q
In the optic chiasma, what lies medial?
A
Crossed temporal fibres lie medial
Uncrossed nasal fibres lie lateral
