[Infra tentorial tumors].

Infra tentorial tumors in adults are half as frequent as supra tentorial tumors. Extra-axial tumours are more frequent, mainly in the cerebellopontine angle cistern: vestibular schwannomas, meningiomas and epidermoid cysts. Tumors of the pons and cerebellum are fewer but medulloblastomas and hemangioblastomas are located primarily in the cerebellum: they are typical tumors of this area. Tumors of the IV ventricle are represented primarily by papilloma and ependymoma. The role of imaging is to ascertain the tumoral nature of the lesion and to determine its location.