Hypoglossal Nerve Schwannoma: Case Report and Literature Review

Hypoglossal schwannomas are rare, benign intracranial neoplasms; they represent 5% of all nonvestibular schwannomas.

A 22-year-old male patient had presented 4 months before admission with left-sided hearing loss, an increase in the base of support with lateralization to the left, and dysphagia to solids. Physical examination on admission showed hypotrophy of the tongue and deviation to the left. Magnetic resonance imaging showed evidence of an extraaxial lesion compressing the medulla oblongata and pons, which protruded through the hypoglossal canal. The patient was prepared for surgical treatment in 2 stages: in the first surgery, a left retrosigmoidal approach with total resection of the intracranial lesion was performed. The biopsy reported a schwannoma, and correlating the signs, symptoms, and imaging, the diagnosis of a hypoglossal nerve schwannoma was established. In the second surgery, a lateral cervical approach was performed, with subtotal resection of the lesion, leaving a remnant adhered to the nerve in the hypoglossal canal.

Hypoglossal schwannomas are a rare entity, in which surgery is the most viable option with high cure rates. However, its complete resection, without leaving permanent neurologic sequels, is a challenge.