trochlear nerve

The trochlear nerve is unique among the cranial nerves in several respects.

Homologous trochlear nerves are found in all jawed vertebrates.

The human trochlear nerve is derived from the basal plate of the embryonic midbrain.

Also apparent are the trochlear nerve nucleus, and the decussation of the superior cerebellar peduncles.

Injury to the trochlear nerve cause weakness of downward eye movement with consequent vertical diplopia (double vision).

The trochlear nerve comes out of the posterior surface of the midbrain, below the inferior colliculus.

The nucleus of the trochlear nerve is located in the midbrain, at the level of the inferior colliculus.

Superior oblique (supplied by Trochlear nerve)

It is the only extraocular muscle innervated by the trochlear nerve (the fourth cranial nerve).

The nucleus of the trochlear nerve is located in the caudal mesencephalon beneath the cerebral aqueduct.

Trochlear nerve palsy also affects torsion (rotation of the eyeball in the plane of the face).

The superior oblique muscle is innervated by cranial nerve IV (trochlear nerve).

Trochlear Nerve (trok'lee-er).

The oculomotor nerve comes out between the peduncles, and the trochlear nerve is visible wrapping around the outside of the peduncles.

Trochlear nerve nucleus: This is the nucleus of CN IV.

Fourth nerve palsy - Trochlear nerve (IV)

Other names for fourth nerve palsy include superior oblique palsy and trochlear nerve palsy.

Excyclotorsion may also be used to describe the condition or state of the eye when a patient has a cranial nerve IV (trochlear nerve) palsy.

Directly rostral to the superior cerebellar peduncle, there is the superior medullary velum and then the two trochlear nerves.

The trochlear nerve emerges from the dorsal aspect of the brainstem at the level of the caudal mesencephalon, just below the inferior colliculus.

To compensate for this, patients with trochlear nerve palsies tilt their heads to the opposite side, in order to fuse the two images into a single visual field.

More rarely, the oculomotor nerve and trochlear nerve (third and fourth nerve palsy, respectively) are affected; both play a role in eye movements.

A slightly elevated ridge, the fraenulum veli, descends upon its upper part from between the inferior colliculi, and on either side of this the trochlear nerve emerges.

Trochlea of superior oblique (see also superior oblique muscle), which is supplied by the so-called trochlear nerve or fourth cranial nerve.

The unique features of the trochlear nerve, including its dorsal exit from the brainstem and its contralateral innervation, are seen in the primitive brains of sharks.