Vol 66, No 2 (2007)
Case report
Published online: 2007-03-09
An unreported variation of the cervical vagus nerve: anatomical and histological observations
Folia Morphol 2007;66(2):155-157.
Abstract
Variations involving the cervical portion of the vagus nerve are seemingly
very rare. We report an adult male found to harbour a right cervical vagus
nerve that crossed anterior to the right common carotid artery to terminate
in the lateral aspect of the thyroid gland. A very small continuation of this
nerve was found to continue distally into the thorax. Histologically, this part of the vagus nerve did not contain ganglion or other cell bodies. There were no heterologous inclusions (thyroid, parathyroid, thymus, salivary gland or branchial cleft remnants) present. Although grossly there was a connection into the thyroid gland, this was not observed histologically. No signs of trauma were found to the ipsilateral neck region. We hypothesise that this variation is due to entanglement between the thyroid gland and cervical vagus nerve during development. This rare variation might be considered by the clinician who operates in the cervical region or interprets imaging of the neck. To our knowledge, a vagus nerve with the above described morphology has not been described.
Keywords: anatomynecknervous systemvariationcranial nerve