Through which foramen does CN VII exit the skull?

Through which foramen does CN VII exit the skull?

• A. Stylomastoid foramen
• B. Foramen ovale
• C. Foramen rotundum
• D. Internal acoustic meatus

Answer: (D)

The facial nerve (CN VII) travels a two-part path through the skull. It enters the skull with the vestibulocochlear nerve (CN VIII) via the internal acoustic meatus, then runs through the facial canal in the petrous part of the temporal bone. It exits the skull through the stylomastoid foramen, which lies between the styloid and mastoid processes just behind the external auditory meatus, to reach the muscles of facial expression. The other foramina serve different nerves: the foramen ovale and foramen rotundum transmit branches of the trigeminal nerve (mandibular and maxillary divisions, respectively).

The facial nerve (CN VII) travels a two-part path through the skull. It enters the skull with the vestibulocochlear nerve (CN VIII) via the internal acoustic meatus, then runs through the facial canal in the petrous part of the temporal bone. It exits the skull through the stylomastoid foramen, which lies between the styloid and mastoid processes just behind the external auditory meatus, to reach the muscles of facial expression. The other foramina serve different nerves: the foramen ovale and foramen rotundum transmit branches of the trigeminal nerve (mandibular and maxillary divisions, respectively).