Oculomotor nerve (English)

The oculomotor nerve (CN III) arises from the oculomotor complex located in the midbrain, ventral to the periaqueductal gray substance, at the level of the superior colliculus. It is comprised of two nuclei: the nucleus of oculomotor nerve (contains cell bodies of general somatic efferent (GSE, motor) neurons), and the accessory nucleus of oculomotor nerve (Edinger-Westphal, contains cell bodies of general visceral efferent (GVE, parasympathetic) neurons). Efferent fibres emerge from the midbrain into the interpeduncular fossa/cistern as the oculomotor nerve, which continues through the lateral wall of the cavernous sinus. From here, it enters the orbit the superior orbital fissure (internal to the common tendinous ring) as two branches which innervate the majority of the extraocular muscles:Superior branch: superior rectus and levator palpebrae superioris muscles.Inferior branch: medial rectus, inferior rectus and inferior oblique muscles.The inferior branch also carries preganglionic parasympathetic fibers which synapse with postganglionic neurons in the ciliary ganglion; these fibers provide parasympathetic innervation to the ciliary and sphincter pupillae muscles responsible for accommodation and pupillary constriction, via the short ciliary nerves.