[A case of intracranial hypoglossal neurinoma (author's transl)]

A case of intracranial hypoglossal neurinoma was reported and the literature was reviewed. A 46-year-old woman with a three-year history of suboccipital pain, dizziness, blurred vision, swallowing disturbance, cysarthria, dysesthesia and weakness of the four extremities, was admitted to our hospital on July 9, 1978. General physical examination on admission were unremarkable. Café au lait spot was not found. Neurological examination revealed nystagmus, ataxic gait and impairment of the finger to nose test on the right side. Atrophy of the tongue with fasciculation on the right side was also noted. Computed tomography demonstrated a round low density area in the posterior fossa which was enhanced with contrast medium. Antero-posterior view of the skull tomography showed enlargement of the right hypoglossal canal. Vertebral angiography and ventriculography disclosed a mass located at the foramen magnum. On July 27, suboccipital craniectomy with C1 laminectomy was performed in prone position. The encapsulated tumor which arouse from the right hypoglossal nerve was totally removed. Histological diagnosis was Antoni A type schwannoma. Postoperative course was uneventful and she was discharged on August 31. Intracranial hypoglossal neurinomas are very rare and our case marks the 17th reported observation of such a lesion. because of their rarity, complicated natural history and variety of associated symptoms and signs, early diagnosis of these lesions is difficult. Among the diagnostic procedures, computed tomography, vertebral angiography and skull tomography were useful for localizing the lesion. Especially skull tomography which showed enlargement of the right hypoglossal canal could offer very important informations. It should be recognized that early diagnosis by means of neurological and radiological maneuvers mentioned above is essential to good prognosis.