An Unusual Bifurcated Proximal Facial Nerve Found During Excision of a Vestibular Schwannoma: Clinical Imaging with a Surgical Video.

Carefully preserving facial nerve function is crucial when using the translabyrinthine approach for vestibular schwannoma surgery. Nerve preservation can only be accomplished by employing rigorous surgical methods and having a thorough understanding of the relevant anatomy, including any variations. Anatomical variations in the path of the facial nerve are infrequent but are most commonly encountered in association with congenital abnormalities of the temporal bone or ossicles. We present a rare case of vestibular schwannoma with a bifurcated facial nerve having 2 origins at the brainstem. The patient underwent a right-sided microsurgical excision using the right translabyrinthine approach. Postoperative recovery went smoothly, resulting in a House-Brackmann scale of Grade I. This case emphasizes the importance of identifying and preserving the facial nerve during vestibular schwannoma resection. To avoid injury, intraoperative neurostimulation should be used to positively identify the facial nerve and its anatomical variations along its entire course.