Due to suspect vascular occlusion characterized by disorders of brainstem function 183 patients were investigated using Doppler sonography of the vertebrobasilary vascular system. Extracranial vascular lesions were diagnosed in 32 patients (basilary steal syndrome, vertebral artery branching stenosis), 11 patients showed bilateral vertebral artery occlusion or basilary thrombosis, nine unilateral intracranial vertebral artery occlusion and 131 patients showed no abnormal findings. The prognostically worse intracranial lesions were all confirmed by angiography. Twenty-five patients with normal Doppler findings were also controlled. Of these, three patients showed macroangiopathy presenting as megadolichobasilary artery and haemodynamically ineffective stenosis of the basilary artery (one patient). In the majority of cases neurological disorders associated with normal Doppler sonography findings were however considered as representative of cerebral microangiopathy, characterized by a favourable prognosis.
