Traumatic arteriovenous fistula of the superficial temporal artery: a histopathologic report.

Traumatic aneurysms, pseudoaneurysms, and arteriovenous (AV) fistulas of the superficial temporal artery (STA) are uncommon, accounting for only 0.5% to 2.0% of all aneurysms subjected to surgery. In the literature that relates to the STA, the general term "aneurysm following traumatic injury" often includes a wide array of pathologic entities, including proper aneurysms, pseudoaneurysms, and AV fistulas. In 75% of cases, such aneurysms are due to blunt trauma. Within this group, STA AV fistulas constitute an exceedingly rare subset. The case presents the occurrence of a traumatic AV fistula of the STA following blunt trauma (karate kick) and provides the first description of the histologic appearance of this lesion.