Iatrogenic external jugular vein pseudoaneurysm: A rare neck mass

External jugular venous pseudoaneurysms are rare and have been previously reported as spontaneous or congenital occurrences. This case describes a 72-year-old female who initially underwent ultrasound-guided needle aspiration of a complex, left supraclavicular cystic mass which subsequently resolved after 2 months. Approximately 4 years later, she returned with complaints of non-tender, left neck swelling in the location of her prior aspiration. Duplex ultrasonography revealed an active, iatrogenic external jugular vein pseudoaneurysm which was confirmed by CT angiography. While complications from venous pseudoaneurysm can arise, most asymptomatic patients do not require treatment and can be followed clinically and with imaging. This case report demonstrates the unusual presentation of an iatrogenic external jugular vein pseudoaneurysm following fine needle aspiration of a neck cyst.