A Case of Extracranial Meningioma Extending to the External Auditory Canal

Choi, Chang Man; Kim, Tae Woon; Song, Byung Uk; Yang, Cheol Min

Abstract

Meningiomas account for approximately 13 to 18 per cent of all primary intracranial neoplasms. The majority of meningioma cases develops in the supratentorial compartment with only 8 to 9 per cent occurring in the posterior fossa. Twenty per cent of intracranial meningiomas eventually develop an extracranial extension. Intracranial tumors that extend to the middle ear and external auditory canal are uncommon. The most common pathway in the temporal bone is through the jugular foramen and foramen lacerum into the parapharyngeal space. When a meningioma gains access to the temporal bone, neurological symptoms usually develop. By the time symptoms become apparent, however, the tumor is usually quite large. The presentation was unusual in that there were no demonstrable neurological signs clinically, despite the large size of the intracranial tumor and mass effect. We experienced a case of extracranial meningioma in the external auditory canal that was extended from intracranial meningioma, and which was diagnosed with biopsy and radiographic examination. In this paper, we report this case with review of literature.