Hyperintense vessel sign in vertebrobasilar dolichoectasia.

Vertebrobasilar dolichoectasia (VBD) is a rare condition characterised by ectasia, elongation and tortuosity in the vertebrobasilar arteries. VBD prevalence ranges from 0.05% to 18%. A possible interplay between vascular risk factors and a predisposing genotype could alter the balance between tunica media matrix metalloproteinases and antiprotease activity. VBD is characterised by the disruption of smooth muscle atrophy, reticular fibre degeneration and multiple gaps in the inner elastic lamina, causing thinning of the tunica media and arterial wall weakening and deformation. VBD can be asymptomatic. VBD is often characterised by ischaemic stroke, intracerebral haemorrhage, brainstem/cranial nerve compression and subarachnoid haemorrhage. Vascular events are the most common clinical manifestation. Slow arterial blood flow results in hyperintense vascular signals, which are linked with a larger infarct and a higher risk of cerebral bleeding. Treatment for VBD is difficult. Currently, there are no specific treatments for VBD, and the available treatments focus on the consequences.