A 74-year-old man presented with a progressive gait disorder, mental impairment and urinary incontinence. MRI showed enlarged lateral ventricles and dolichoectasia of vertebrobasilar and carotid arteries, with prominent compression of the lower brainstem. An evacuative lumbar puncture improved the symptoms only marginally.

The most common clinical presentations of dilatative arteriopathy include acute brain ischemia and progressive compression of cranial nerves [1], and less frequently gait ataxia, pseudo-parkinsonism and cognitive impairment [2]. A possible explanation for the enlarged ventricles is the basilar artery lifting the floor of the third ventricle [1]. Figure. 1.

Fig. 1
figure 1

Dolichoectasia of the intracranial arteries. Note the dolichobasilar artery compressing and displacing the medulla oblongata (straight arrow) and lifting the floor of the third ventricle (dashed arrow)