IV Trochlear

Question 1

Where do the Trochlear nerves originate?

Answer 1

Trochlear nucleus
Midbrain at level of inferior colliculus, in anterior portion of periaqueductal grey

Question 2

Where does Trochlear Nerve decussate and exit the brain?

Answer 2

Decussate at superior medullary velum, exit inferior to inferior colliculi

Question 3

Function of Trochlear nerves

Answer 3

Extraocular movements (superior oblique muscles)

Question 4

Examination of Trochlear nerve

Answer 4

Downward and inward eye movements

Question 5

Lesion of Trochlear nerve

Answer 5

Diplopia when looking down and in and head tilt to opposite side

Question 6

Where does Trochlear nerve exit the skull?

Answer 6

Superior orbital fissure