A 50-year-old healthy man presented with a lump on the temporal side of his head. Six weeks before, he fell off his mountain bike, hitting the ground with the left side of his head while wearing a helmet. Initially, there were no signs of injury, but after a few weeks a progressive painless lump has appeared at the place where his head smashed into the helmet at the time of the accident. Physical examination revealed a smooth lump, measuring 1 cm with no signs of inflammation or tenderness (Fig.1)
Ultrasonography showed a dilated vessel with a minor defect of the luminal wall. Our patient was treated by excision of the swelling, which turned out to be an aneurysm of the STA (Fig.2).The diagnosis was reconfirmed in the pathological report. The patient recovered uneventfully.