Unilateral, double hypoglossal nerves leaving the cranial cavity through two hypoglossal foramina - A case report

Hypoglossal nerve is the twelfth cranial nerve. It functionally and clinically important since it is supplies most of the muscles of the tongue. Here we report the doubling of the left hypoglossal nerve. The hypoglossal nerve of the left side had two roots which pierced the dura separately and entered two hypoglossal canals and reunited in the occipital bone and emerged out of the skull as a single hypoglossal nerve. Knowledge of this anatomical variation may be important to various fields of medicine.