CN III (Oculomotor), IV (Trochlear), VI (Abducens) {SO4,LR6,Rest3)

Question 1

These cranial nerves are grouped together because they innervate what?

Answer 1

Extra-ocular muscles

Question 2

CNIII (oculomotor) supplies all extra ocular muscles of the eye specifically?

Answer 2

Superior Rectus (up)
Inferior Rectus (down)
Medial Rectus (in)
Inferior Oblique (up and out)

Question 3

CN III does not innervate which eye muscles?

Answer 3

Superior oblique

Lateral Rectus

Question 4

CN III also carries parasympathetic fibers to what?

Answer 4

Circular iris muscle

Ciliary body via ciliary ganglion from Edinger-westphal nucleus located in midbrain

Question 5

The parasympathetic fibers are responsible for what?

Answer 5

Constriction of pupil in iris

Lens accommodation

Question 6

CN IV (trochlear) supplies what muscle?

Answer 6

Superior Oblique (down and out)

Question 7

The superior oblique muscle is tested clinically by asking the patient to do what?

Answer 7

Look in and then down

Question 8

CN IV is the only CN that exits brainstem how?

Answer 8

Dorsally

Question 9

CN VI (abducens) innervates what muscle?

Answer 9

lateral Rectus (abducts eye)