Pseudoaneurysm at the Distal Posterior Inferior Cerebellar Artery After Blunt Head Trauma: A Case Report and Review of the Literature.

BACKGROUND: Traumatic pseudoaneurysm of the distal posterior inferior cerebellar artery (PICA) is extremely rare. We report our experience of a case of pseudoaneurysm that developed on the PICA after blunt trauma to the head.

CASE DESCRIPTION: A 55-year-old woman was transferred to our emergency department presenting with a semicomatose mental status after falling to the floor from a standing position. Computed tomography showed a small intracerebral hemorrhage and subarachnoid hemorrhage in the cerebellum. Cerebral angiography revealed no causative lesion. After 3 days, the woman was nearly mentally alert. One month later, follow-up angiography showed a small, newly developed saccular aneurysm at the distal PICA. The patient underwent surgical treatment via a midline suboccipital approach. The aneurysm was surrounded by a subacute-stage subdural hematoma and protruded into the cortex. The aneurysm was coagulated and resected. On pathologic examination, pseudoaneurysm was diagnosed without infectious inflammation. No surgery-related morbidity occurred.

CONCLUSIONS: Given that development of traumatic pseudoaneurysm usually is delayed, follow-up radiologic examination is required, especially for patients with severe blunt trauma.