Managing Multiple Schwannomatosis of Vagus and Hypoglossal Nerves: The Unanticipated Complications

Schwannomas are rare benign tumours of the nerve sheath. Extracranial schwannomas are usually found solitary, in the absence of other features of neurofibromatosis. The non NF1/2 multiple schwannomas are collectively described as the clinical scenario called schwannomatosis. We present a rare case of two extracranial schwannomas involving vagus and hypoglossal nerves in a 22-year-old female along with an unusual surgical complication of CSF leak presenting as post-op neck mass and a review of previously reported similar cases. A thorough literature search using the MeSH terms—‘schwannomatosis’ or ‘Multiple Schwannoma’ and ‘Vagal Schwannoma’ and ‘Hypoglossal Schwannoma’, was conducted using online databases and augmentated by hand search. A total of 13 reported cases were found and reviewed. Of the 14 cases described from review of literature and our case, 50% had involvement of vagus nerve as one of the components. 12.5% had hypoglossal and cervical sympathetic plexus involvement each. All patients underwent surgical excision. Half of the patients suffered intraoperative nerve sacrifice with resultant severe functional deficits like vocal cord paralysis, Horners syndrome, hypoglossal palsy, facial palsy and eleventh nerve palsy. In our case, there was un-unusual complication of CSF leak presenting as a cervical neck mass. Multiple extracranial head and neck schwannomas are rare and their management is fraught with several complications. Decision to operate is often perplexing. However, early planned surgical excision and preservation of nerve of origin minimizes the impact on quality of life postoperatively.