Primary extracranial meningioma of paranasal sinuses.

Meningioma is the most common nonglial intracranial neoplasm, arising from meningocytes (arachnoid cap cells) of arachnoid granulation tissue and constitutes 15-20 % of all intracranial tumors. Approximately 6-17 % of all meningiomas can be found in extracranial or extra spinal sites. The head and neck is the most frequent location of extraneuraxial meningiomas, commonly seen as an extension of primary intracranial tumor (secondary extracranial meningioma).