Stylomastoid foramen

The stylomastoid foramen can be found at the bottom of the skull, nestled between the styloid and mastoid processes of the temporal bone. This foramen marks the end point of the facial canal and serves as a passageway for both the facial nerve and the stylomastoid artery.

• After the facial nerve emerges from the stylomastoid foramen, it weaves its way through the parotid gland and ultimately provides innervation to the muscles responsible for facial expressions.

• The stylomastoid artery, originating as a diminutive branch of the posterior auricular artery—which itself is a derivative of the external carotid artery—enters the facial canal by way of the stylomastoid foramen. In doing so, it delivers blood to the facial nerve (cranial nerve VII), and the mastoid air cells. Additionally, this artery plays a part in the vascularization of the tympanic membrane (the ear drum).