Bilateral Abducens Paralysis Secondary to Compression of Abducens Nerve Roots by Vertebrobasilar Dolichoectasia.

Vertebrobasilar dolichoectasia is characterized by dilatation, tortuosity, and marked elongation of the vertebral and basilar arteries. Dolichoectatic arteries usually have thin arterial walls secondary to degeneration of the internal elastic lamina, reticular fibre deficiency, and smooth muscle atrophy. This anomaly is relatively uncommon and generally asymptomatic. Clinical manifestations of dolichoectasia result from the compression and displacement of adjacent structures, causing cranial nerve palsy, obstructive hydrocephalus, or ischaemic stroke. The authors present a case in which vertebrobasilar dolichoectasia led to the development of bilateral abducens nerve paralysis in a 9-year-old girl.