The labyrinthine artery, also known as the auditory artery or internal auditory artery, is a long and slender artery that is the main arterial supply to the vestibular apparatus and cochlea. It also vascularizes the VII and VIII cranial nerves.
It usually originates from the AICA (~85%), although it can also branch from the basilar artery (~15%), vertebral artery (~5%) or even superior cerebellar artery.
From its origin, it accompanies the vestibulocochlear nerve and passes into the internal acoustic meatus where it divides into two branches:
anterior vestibular artery
common cochlear artery, which further divides into
proper cochlear artery
vestibulocochlear artery: gives of a vestibular ramus and a cochlear ramus
The labyrinthine artery (auditory artery, internal auditory artery), a long slender branch of the anterior inferior cerebellar artery (85%-100% cases) or basilar artery (<15% cases), arises from near the middle of the artery; it accompanies the vestibulocochlear nerve through the internal acoustic meatus, and is distributed to the internal ear.
Spasm is thought to be one of the causes of postoperative sensory hearing loss after attempted hearing preservation removal of an vestibular schwannoma. The use of topical papaverine, a nonspecific vasodilator, to prevent vascular insufficiency to the inner ear and to improve hearing outcomes has been suggested but not proven.
An animal model of vasospasm was described. Mechanically induced vasospasm was prevented by the topical application of papaverine. These findings have clinical implications for surgical procedures involving the internal auditory canal/cerebellopontine angle such as vestibular schwannoma removal 1).