Diagnosis of Traumatic Temporal Artery Pseudoaneurysm by Ultrasound in the Emergency Department.

BACKGROUND: Emergency bedside point-of-care ultrasound provides an extremely fast and cost-effective diagnostic modality for the diagnosis of vascular abnormalities, such as pseudoaneurysms. The cost-benefit and timing advantages of ultrasound are increasingly apparent when compared to more conventional diagnostic tests, such as computed tomography angiography and magnetic resonance angiography scans. CASE REPORT: A 33-year-old man with no medical history presented to our emergency department complaining of a constant, throbbing, left-sided headache over his temple with an associated mass. The physical examination revealed a 0.5-cm, tender, flesh-colored, pulsatile mass over his left temple. The tender mass was evaluated at the bedside by an emergency physician with a linear array L-14 probe on the ZONARE ultrasound system (ZONARE Medical Systems, Inc., Mountain View, CA). A small anechoic collection adjacent to the superficial temporal artery was identified with a sac containing flow in a prototypical "yin and yang" pattern. These findings were consistent with a superficial temporal artery pseudoaneurysm. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: We present this case report because of the implications of missing the diagnosis. Emergency physicians should be aware of the possible diagnosis of pseudoaneurysm of the temporal artery because of the plethora of head injuries that we evaluate on a regular basis. Missing the diagnosis can lead to delayed neurologic sequela and potential life-threatening bleeding in patients presenting with what appears to be a minor complaint.