Abstract
BACKGROUND: The thyroid ima artery (ThIA) is a rare anatomical anomaly, commonly branching from the brachiocephalic artery. Thyroid ima artery injury can cause severe mediastinal hematoma because its descending branch extends into the mediastinum. CASE PRESENTATION: A 91-year-old man presented with syncope after a motor vehicle accident. A bruise on the chest was evident. Contrast-enhanced computed tomography revealed a massive mediastinal hematoma with signs of active hemorrhage. Injury to a descending branch of the ThIA was indicated. Transcatheter arterial embolization (TAE) was successful in stopping the bleeding. CONCLUSIONS: Although a ThIA injury is rare, it can cause serious mediastinal hematoma. Thyroid ima artery injury should be considered as a cause of traumatic mediastinal hematoma. Transcatheter arterial embolization for traumatic ThIA injury is considered a safe and effective treatment.