supratrochlear nerve supratrochlear nerve the supratrochlear nerve is a branch of the frontal nerve, itself a branch of the ophthalmic nerve (cn v1) from the trigeminal nerve (cn v). it provides sensory innervation to the skin of the forehead and the upper eyelid. not to be confused with infratrochlear nerve. supratrochlear nervesensory areas of the head, showing the general distribution of the three divisions of the fifth nerve. (supratrochlear nerve labeled at upper left.)nerves of the orbit. seen from above. (supratrochlear nerve visible near top.)detailsfromfrontal nerveidentifierslatinnervus supratrochlearista98a14.2.01.024ta26203fma52642anatomical terms of neuroanatomy structure origin the supratrochlear nerve is the smaller of the two terminal branches of the frontal nerve (the other being the supraorbital nerve). it arises midway between the base and apex of the orbit where the frontal nerve splits into said terminal branches. course the supratrochlear nerve passes medially above the trochlea of the superior oblique muscle. it then travels anteriorly above the levator palpebrae superioris muscle. it exits the orbit through the supraorbital notch or foramen. it then ascends onto the forehead beneath the corrugator supercilii muscle and frontalis muscle. it finally divides into sensory branches. the supratrochlear nerve travels with the supratrochlear artery, a branch of the ophthalmic artery. branches before exiting the orbit, the supratrochlear nerve emits a descending branch to the infratrochlear nerve. function the supratrochlear nerve provides sensory innervation to the skin and conjunctiva of the upper eyelid, and the skin of the inferomedial forehead. it may also provide sensory innervation to part of the periosteum of the frontal bone. clinical significance the supratrochlear nerve may be anaesthetised for surgery of parts of the scalp. this can be used for small lesions of the scalp. it can also be used for more extensive injury to the scalp. it is often anaesthetised alongside the supraorbital artery. etymology the supratrochlear nerve is named for its passage above the trochlea of the superior oblique muscle. additional images supratrochlear nerve extrinsic eye muscle. nerves of orbita. deep dissection. extrinsic eye muscle. nerves of orbita. deep dissection. extrinsic eye muscle. nerves of orbita. deep dissection. extrinsic eye muscle. nerves of orbita. deep dissection. extrinsic eye muscle. nerves of orbita. deep dissection.