SIGNIFICANCE OF PETROSAL VEIN IN DIAGNOSIS OF CEREBELLOPONTINE ANGLE TUMORS

With proper angiographic technic, both petrosal veins can be visualized on half-axial views in more than 73% of catheter vertebral angiograms. Roentgenographic anatomy of the petrosal vein and its tributaries is described on the basis of 84 normal vertebral angiograms and dissections of 10 autopsy specimens. In review of 12 cerebellopontine angle tumors, displacement and stretching of the petrosal vein and its tributaries were diagnostic of and expanding lesion in the cerebellopontine angle, whereas nonvisualization in the presence of good filling of the posterior inferior cerebellar artery on the same side was an accessory sign in a mass of the cerebellopontine angle. The control study with 24 expanding lesions in the cerebellum and the pons did not reveal any displacement of the petrosal vein, but nonvisualization or compression of the vein against the petrous bone was present in a small number of these lesions.