1987 Volume 9 Issue 1 Pages 62-67
It is uncommon that cerebral aneurysm is determined as thromboembolic origin and produces ischemic cerebrovascular accident. These events rarely occurs in the territory of posterior cirsulation and only five such cases have been reported.
This 53-year-old man admitted because of a sudden onset of vertigo, nausea and vomiting on Jan 7, 1983. Neurological examination revealed bilateral horizontal nystagmus and ataxia of left upper and lower extremities. A CT scan on admission revealed no particular finding, but a low density area of the left cerebellar hemisphere with internal hydrocephalus was noted on CT taken at three days later. The brachial angiogram showed no abnormal feature in the region of extracranial vertebral and subclavian arteries. But on the left vertebral artery, an aneurysm of the left posterior inferior cerebellar aetery (PICA) and obstruction of the left tonsillo-hemisheric branch of PICA were disclosed. At 8 weeks after onset, an exploratory suoccipital craniectomy was performed. The operation confirmed that the aneurysm on the left PICA was not saccular but fusiform in the shape and it was adhered to ventral surface of the medulla oblongata. The separation of the adhesions and trapping of PICA were impossible because of several perforating arteries originating from the PICA to the brain stem. The coating of fusiform aneurysm with Biobond was then perfimed. No additional neurological deficit was noted postoperatively. On April 28, 1983, the patient became almost asymptomatic and returned to the normal activity.
In this case, the cerbellar infarction was possibly by thromboembolism originated from the fusiformaneurysm because there were no cardiogenic factor nor extracranial embolic source. The principle of management for the aneurysm presenting as a thromboembolic event was discussed with reviewing the literature.
