Pseudoaneurysm of the superficial temporal artery after blunt trauma: case report and literature review.

An 88-year-old man presented with a left temporal pulsatile mass that developed after blunt trauma. Based on suspicion of hematoma, needle aspiration was performed with the removal of approximately 15 mL of blood. No evident improvement was noted, and active arterial bleeding was observed at the needle puncture site. Doppler ultrasonography revealed a "yin-yang" sign, and the mass was diagnosed as a pseudoaneurysm of the left superficial temporal artery. Under general anesthesia, the superficial temporal artery was ligated and the pseudoaneurysm was removed. Superficial temporal artery pseudoaneurysm is a rare facial tumor that generally occurs after blunt trauma. Due to its rarity, pseudoaneurysms are often misdiagnosed as hematoma. The treatment of choice is excision, although endovascular intervention is a potential treatment option. However, when a pseudoaneurysm is small, conservative treatment can be used.