This lesion arises from right glossopharyngeal nerve in the anterior jugular foramen (pars nervosa). The patient underwent retromastoid suboccipital craniotomy and excision of the mass, confirming the diagnosis.
Cranial nerve schwannomas account for about 8-10 % of the brain tumors. The most common nerve involved is the vestibular division of the vestibulocochlear nerve (CN VIII). This is followed by trigeminal (V), facial (VII) and hypoglossal (XII) nerves.
Schwannomas arising from the 9th,10th, and 11th cranial nerves are called jugular foramen schwannomas. There are only 37 recorded cases of glossopharyngeal nerve schwannomas. Incidence without neurofibromatosis is very rare.