Case Report: Facial Nerve Bifurcation Noted During Resection of Vestibular Schwannoma.

BACKGROUND AND IMPORTANCE: Resection of cerebellopontine angle tumors is challenging because the proximity of the facial nerve puts it at risk of inadvertent injury and subsequent dysfunction. It is critical to consider variations in anatomy and be aware of the potential deviations in the course of the nerve in order to avoid damage. CLINICAL PRESENTATION: We present a case of a facial nerve bifurcation identified during resection of a vestibular schwannoma. CONCLUSION: This is the only reported case of proximal facial nerve bifurcation. We review what is known about variations in proximal facial nerve anatomy, the rates of facial nerve injury after schwannoma resection, and the importance of neuromonitoring in identifying the nerve and predicting function postoperatively. Ultimately, understanding possible anatomic variations in the nerve is critical to minimize iatrogenic injury during surgery.