Facial nerve communication with ansa cervicalis - An unusual anatomical variation.

Abstract

Neural connections of the seventh cranial nerve with its neighboring nerves are common and well documented; however, communication with ansa cervicalis is as yet unknown. We present a case with such a connection found during cadaveric dissection, with hitherto unknown consequences. In this specimen, after giving the marginal mandibular and cervical branches, the cervicofacial division continued distally to communicate with the distal loop of ansa cervicalis. Presence of such connection may result in facial muscle paralysis on injury to the ansa or strap muscle paralysis on injury to the facial nerve, depending on the direction of nerve fibers. Such unusual connections bring to light the need for extreme care during surgeries in the neck to safeguard any such connections and when using the ansa as donor.