[Basilar ectasia and stroke: clinical aspects of 21 cases].

Ectasia of the basilar artery (EB) occurs when its diameter is greater than normal along all or part of its course, and/or when it is abnormally tortuous. EB may cause cranial nerve dysfunction, ischemic stroke or subarachnoid hemorrhage, pseudotumor or hydrocephalus. We tried to describe cases of stroke associated with EB, analyze its frequency, clinical aspects, and the mechanisms involved in different forms of its presentation. We found 21 patients with stroke and EB. The association between EB and stroke was more prevalent in males over the age of fifty. Main symptoms were hemiparesia, cranial nerves dysfunction, and cerebellar ataxia. Cerebral infarcts associated with EB were due to different mechanisms: arterial thrombosis, artery-to-artery embolism, mass effect with angulation and obstruction of the vertebral and basilar branches.