The pathogenesis of essential hypertension still remains unclear. Recently, it has been supposed, that an arterial compression of the left root entry zone (REZ) of the cranial nerves IX and X by looping arteries may play a pathogenetic role. In this report we verified this hypothesis retrospectively by vertebral angiographies in 99 hypertensive and 57 normotensive patients. The angiographic findings were compared with the results obtained from an anatomic study, in which the positions of 10 left vagus/glossopharyngeal nerves in the skull were radiographically determined in 10 cadavers. By using a pattern of REZ topography developed from this information we obtained the following results: In 81% of the evaluable angiographies of hypertensive patients we found an artery in the left REZ of cranial nerves IX and X. The normotensive patients showed an artery in the REZ only in 41.7% of cases. Our results support the hypothesis that essential hypertension may be combined with neurovascular compression of the left REZ of cranial nerves IX/X.