[Angiographic findings in 86 confirmed tumours of the posterior cranial fossa (author's transl)].

The accuracy of vertebral angiography in the diagnosis of tumours was reviewed on the basis 368 selective angiograms. The greatest accuracy was achieved with space-occupying lesions situated centrally in the cerebellum in the region of the fourth ventricle or in the vermis. However, tumours growing eccentrically, but arising in this region, were occasionally missed. Least reliable is the angiographic diagnosis of tumours is the cerebellar hemispheres. Of these, only about two-thirds could be demonstrated. Only 60% of cerebello-pontine tumours were diagnosed from displacement of various structures, another 10% by the presence of pathological vessels or tumour staining. The classic angiographic picture of pontine tumours is rare. Brain stem tumours are frequently eccentric and may simulate cerebello-pontine angle tumours. The demonstration or exclusion of brain stem involvement can be difficult. In view of the implications for treatment, this should, however, always be attempted.