Superficial Temporal Artery Pseudoaneurysm Secondary to a Galeal Hook: A Case Report.

The superficial temporal artery (STA) is one of the final branches of the external carotid artery. STA pseudoaneurysms are a rare vascular complication following blunt trauma, and even rarer following craniotomy. A 44-year-old man presented to hospital with altered level of consciousness and left-sided paresis. Neuroimaging showed a right middle cerebral artery bifurcation aneurysm, subarachnoid hemorrhage, and a large right-sided intracerebral hematoma (ICH). An emergent fronto-temporo-parietal craniotomy was performed for hematoma evacuation and clipping of the ruptured aneurysm. On postoperative day 21, the patient developed sudden-onset scalp swelling and a decline in neurological status. Computed tomography imaging showed a ruptured STA pseudoaneurysm, creating a subgaleal hematoma that tracked through the burr hole cover, dural leaflets, and into the brain to create an ICH. An emergent craniotomy for hematoma evacuation and STA resection was done. STA pseudoaneurysms are rare following a craniotomy. Only one previous case has been reported of a pseudoaneurysm secondary to a galeal hook. Neurosurgeons frequently encounter the STA. It is imperative to be mindful of the placement of scalp retractors to avoid STA injury and further postoperative complications.