Stylomastoid foramen is the foramen found between the styloid process and the mastoid process of the temporal bone in the skull. This lies on the inferior surface of the petrous temporal bone. A foramen basically means any opening. There are many foramina in the human body and the most important one is the foramen magnum.
Stylomastoid Foramen Clinical Significance
Stylomastoid foramen is where the facial canal terminates. The facial canal is a z shaped canal which runs through the temporal bone. It runs between internal acoustic meatus and the stylomastoid foramen. Also called as the Fallopian Canal, the facial canal contains the facial nerve, which is the VIIth Cranial nerve.
Contents Found In the Foramen
The facial nerve and the stylomastoid artery pass through this foramen. The facial nerve typically travels from the pons via the facial canal in the temporal bone and comes out of the skull at the stylomastoid foramen.
The stylomastoid artery is a branch of the posterior auricular artery and is a part of the external carotid arterial system. It enters the foramen and gives the arterial supply to the tympanic cavity, the tympanic antrum, mastoid cells, and the semicircular canals.
Recommended reading for all the human anatomy and physiology students and enthusiasts: The human anatomy and physiology course
Bells Palsy and It’s Relation To The Foramen
Bell’s palsy is a condition characterized by facial paralysis where the affected individual is unable to control the facial muscles on the affected side. They can be mild, moderate or severe.
Although the exact cause isn’t known, Bell’s Palsy usually results from the inflammation of the facial nerve. This is commonly seen to be occurring in the area where the facial nerve just leaves the stylomastoid foramen.
Signs and symptoms of Bell’s Palsy may include muscle twitching, inability to move the muscles on the affected side or sometimes both the sides, drooling, dropping of the eyelid and increased sensitivity to sound.