CN2 Optic nerve

Question 1

What is cranial nerve 2?

Answer 1

Optic nerve

Question 2

What covers the CN2 optic nerve? Why?

Answer 2

Meninges

because it arises from the forebrain

Question 3

What does the CN2 optic nerve innervate?

Answer 3

Retina

Question 4

What is the route of the CN2 optic nerve from its innervation to origin?

Answer 4

From optic disc
passes through optic canal
runs to optic chiasm
forms optic tracts
to primary visual cortex in occipital lobe

Question 5

What is the optic disc?

Answer 5

Where the optic nerve meets the retina

Question 6

Where is the optic chiasm located?

Answer 6

Superiorly to the pituitary gland

Question 7

What happens at the optic chiasm?

Answer 7

Fibres from the right and left optic nerves mix

Question 8

What is the function of the CN2 optic nerve?

Answer 8

Special sensory - vision

Question 9

What does damage to the CN2 optic nerve result in?

Answer 9

Loss of vision in ipsilateral eye

Question 10

What does damage to the optic chiasm result in?

Answer 10

Loss of vision in both eyes

Question 11

How does a pituitary tumour affect the optic chiasm?

Answer 11

Compresses the optic chiasm

Question 12

How does a pituitary tumour compressing the optic chiasm present?

Answer 12

Bi-temporal hemianopsia

meaning tunnel vision