Foramina & Other Apertures of the Cranium

Where does the olfactory nerve (CNI) exit the internal cranium?

Cribriform plate - of the ethmoid bone

Where does the optic nerve (CNII) exit the internal cranium?

Optic canal - of sphenoid bone

where does the oculomotor (CNIII) exit the cranium?

Superior orbital fissure

where doe the trochlear nerve (CNIV) exit the cranium?

superior orbital fissure

where does the ophthalmic nerve, 1st division of the trigeminal nerve (CNV) exit the cranium?

Superior orbital fissure

where does the abducens nerve (CNVI) exit the cranium?

superior orbital fissure

where does the maxillary nerve, 2nd division of trigeminal nerve (CNV) exit the cranium?

foramen rotundum

where does the mandibular nerve, 3rd division of the trigeminal nerve (CNV) exit the cranium?

foramen ovale

where does the middle meningeal artery enter the cranium?

Foramen spinosum

where does the facial nerve (CNVII) exit the cranium?

Internal acoustic meatus

where does the vestibulocochlear nerve (CNVIII) exit the cranium?

internal acoustic meatus

where does the internal carotid artery enter the cranium?

Carotid canal

where does the internal jugular vein exit the cranium?

jugular foramen

where does the glossopharyngeal nerve (CNIX) exit the cranium?

jugular foramen

where does the vagus nerve (CNX) exit the cranium?

jugular foramen

where does the spinal accessory nerve (CNXI) exit the cranium?

jugular foramen

where does the hypoglossal nerve (CNXII) exit the cranium?

hypoglossal canal

where do the vertebral arteries enter the cranium?

foramen magnum

where does the spinal cord/ medulla exit the cranium?

foramen magnum

what exits the cribriform plate?

olfactory nerve (CNI)

what exits the optic canal?

Optic nerve (CNII)

what exits the superior orbital fissure?

• Oculomotor nerve (CNIII),

• trochlear nerve (CNIV)

• ophthalmic nerve, 1st division of trigeminal nerve (CNV)

• abducens nerve (CNVI)

what exits the foramen rotundum?

• maxillary nerve, 2nd division if Trigeminal (CNV)

what exits the foramen ovale?

mandibular nerve, 3rd division of trigeminal (CNV)

what enters the foramen spinosum?

middle meningeal artery

what exits the internal acoustic meatus?

• facial nerve (CNVII)

• vestibulocochlear nerve (CNVIII)

what enters the carotid canal?

internal carotid artery

what exits the jugular foramen?

• internal jugular vein

• glossopharyngeal neve (CNIX)

• vagus nerve (CNX)

• Spinal accessory nerve (CNXI)

what exits the hypoglossal canal?

hypoglossal nerve (CNXII)

what enters/exits the foramen magnum?

• vertebral arteries

• spinal cord/ medulla