Voorbeelden van trochlear nerve

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

• This is due to impairment in the superior oblique muscle innervated by the trochlear nerve.

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

• By 1998, there had been only one reported case of compression of the trochlear nerve by vessels.

• The trochlear nerve supplies the superior oblique muscle, and when this muscle is non-functional (as in trochlear palsy) the eye "excyclotorts"; i.e. twists/rotates outward.

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

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

• On either side of this band the trochlear nerve emerges, and passes forward on the lateral aspect of the cerebral peduncle to reach the base of the brain.

• The eye will be displaced downward, because the superior oblique (innervated by the fourth cranial or trochlear nerve), is unantagonized by the paralyzed superior rectus, inferior rectus and inferior oblique.

• Damages to these structures produce the ipsilateral presentation of paralysis or palsy due to the lack of cranial nerve decussation (aside from the trochlear nerve) before innervating their target muscles.

• Superior oblique myokymia is an uncommon neurological condition caused by vascular compression of the trochlear nerve resulting in repeated, brief, involuntary episodes of movement of the eye.

• More over, while the abducens and the trochlear nerve each innervate one specific muscle, the oculomotor nerve has many functions including eyelid retraction and pupil constriction.

• It sometimes receives a filament from the trochlear nerve, but this is possibly derived from the branch that goes from the ophthalmic to the trochlear nerve.

• 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.

• 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.