An unusual location of the ansa cervicalis

The ansa cervicalis (AC) is part of the cervical plexus and is formed by the ventral rami of spinal nerves C1-C3. It is usually formed by two roots that run parallel to each other and then form a loop anterior to the internal jugular vein. Herein, we report a rare case where the AC was found deep to the internal carotid artery and common carotid artery and had sympathetic contributions.