[Meningiomas of the posterior cranial fossa].

In a period of 3 years 12 patients with meningiomas of the posterior cranial fossa were treated surgically. The group included 2 cases of meningioma situated on the cerebellar convexity, 5 on the tentorium, 2 on the posterior aspect of the pyramid bone, 1 of Blumenbach clivus, 2 of foramen magnum. The neurological findings and pneumoencephylographic changes in cases of meningiomas of cerebellar convexity, tentorium and posterior aspect of the pyramid bone made possible the diagnosis of posterior fossa tumour and the diagnosis of meningioma was made possible by carotid and vertebral angiography. In the case of Blumenbach clivus meningioma and in foramen magnum meningiomas the neurological changes were characteristic of tumours at the craniovertebral junction. One meningioma growing through the tentorium was approached from the middle cranial fossa, the remaining ones from the posterior cranial fossa. The tumour could have been removed radically in 7 cases. In 5 cases only partial removal was possible. Three patients died, two after operations for tentorial meningioma and one after operation for Blumenbach clivus tumour. The results in the remaining cases were good.