Agenesis of the cervical internal carotid artery

Total or segmental agenesis of the internal carotid artery is a rare anomaly. The cervical portion of the internal carotid artery was absent in the right side of the patient who was carried out radical surgery due to recurrent oropharyngeal cancer. Post-operative venous digital subtraction angiography revealed that the remaining intracranial portion of the internal carotid artery was normally patent and supplied blood flow via ipsilateral external carotid artery. Otolaryngologist-Head and Neck surgeon should know such a vascular anomaly and avoid a disastrous result on dividing the external carotid artery.