A pituitary tumour may also extend into the cavernous sinus, compressing the oculuomotor nerve ( III ), trochlear nerve ( IV ) and abducens nerve ( VI ), leading to double-vision and strabismus.
22.
Sudden onset hypertropia in a middle aged or elderly adult may be due to compression of the trochlear nerve and mass effect from a tumor, requiring urgent brain imaging using MRI to localise any space occupying lesion.
23.
The interposition of a Teflon pad between the trochlear nerve and a compressing artery and vein at the nerve's exit from the midbrain led to a remission lasting for a follow-up of 22 months.
24.
The sixth nerve, the abducens nerve, which innervates the lateral rectus muscle of the eye ( moves the eye laterally ), is also commonly affected but fourth nerve, the trochlear nerve, ( innervates the superior oblique muscle, which moves the eye downward ) involvement is unusual.
25.
Cavernous sinus syndrome may result from mass effect of these tumors and cause ophthalmoplegia ( from compression of the oculomotor nerve, trochlear nerve, and abducens nerve ), ophthalmic sensory loss ( from compression of the ophthalmic nerve ), and maxillary sensory loss ( from compression of the maxillary nerve ).
26.
The branch of communication with the oculomotor nerve joins that nerve at its point of division; the branch to the trochlear nerve joins it as it lies on the lateral wall of the cavernous sinus; other filaments are connected with the under surface of the ophthalmic nerve; and a second filament joins the abducent nerve.
27.
It transmits the oculomotor nerve, the trochlear nerve, and the abducent nerve, the three branches of the ophthalmic division of the trigeminal nerve, some filaments from the cavernous plexus of the sympathetic nervous system, the orbital branch of the middle meningeal artery, a recurrent branch from the lacrimal artery to the dura mater, and the ophthalmic vein.
28.
Because Latin was the " lingua franca " ( common language ) of the study of Anatomy when the nerves were first documented, recorded, and discussed, many nerves maintain Latin or Greek names, including the trochlear nerve ( IV ), named according to its structure, as it supplies a muscle that attaches to a pulley ( ).
29.
It is the smallest of the three divisions of the trigeminal, and arises from the upper part of the trigeminal ganglion as a short, flattened band, about 2.5 cm . long, which passes forward along the lateral wall of the cavernous sinus, below the oculomotor and trochlear nerves; just before entering the orbit, through the superior orbital fissure, it divides into three branches, lacrimal, frontal, and nasociliary.
