All cranial nerves and foramina where they pass from

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Here is a complete reference table of all 12 cranial nerves and the foramina/openings through which they exit the skull:

All 12 Cranial Nerves and Their Foramina

#	Nerve	Foramen / Opening	Skull Fossa
CN I	Olfactory	Cribriform plate (foramina of the ethmoid bone)	Anterior cranial fossa
CN II	Optic	Optic canal	Middle cranial fossa
CN III	Oculomotor	Superior orbital fissure	Middle cranial fossa
CN IV	Trochlear	Superior orbital fissure	Middle cranial fossa
CN V₁	Trigeminal — Ophthalmic	Superior orbital fissure	Middle cranial fossa
CN V₂	Trigeminal — Maxillary	Foramen rotundum → infraorbital foramen (exits face)	Middle cranial fossa
CN V₃	Trigeminal — Mandibular	Foramen ovale → mental foramen (exits face)	Middle cranial fossa
CN VI	Abducens	Superior orbital fissure	Middle cranial fossa
CN VII	Facial	Internal acoustic meatus → exits skull via stylomastoid foramen	Posterior cranial fossa (enters); temporal bone (exits)
CN VIII	Vestibulocochlear	Internal acoustic meatus	Posterior cranial fossa
CN IX	Glossopharyngeal	Jugular foramen	Posterior cranial fossa
CN X	Vagus	Jugular foramen	Posterior cranial fossa
CN XI	Accessory (Spinal)	Spinal rootlets enter skull via foramen magnum, then exits via jugular foramen	Posterior cranial fossa
CN XII	Hypoglossal	Hypoglossal canal (anterior condylar canal)	Posterior cranial fossa

Foramen	Cranial Nerves Passing Through	Also Contains
Cribriform plate	CN I	Anterior ethmoidal artery
Optic canal	CN II	Ophthalmic artery
Superior orbital fissure	CN III, IV, V₁, VI	Superior ophthalmic vein
Foramen rotundum	CN V₂	—
Foramen ovale	CN V₃	Accessory meningeal artery
Foramen spinosum	—	Middle meningeal artery (no cranial nerve)
Internal acoustic meatus	CN VII, VIII	Labyrinthine artery
Stylomastoid foramen	CN VII (exit)	—
Jugular foramen	CN IX, X, XI	Internal jugular vein, sigmoid sinus
Foramen magnum	CN XI (entry), brainstem–spinal cord junction	Vertebral arteries, anterior/posterior spinal arteries
Hypoglossal canal	CN XII	—

"Standing Room Only" (Superior Orbital Fissure): CN III, IV, V₁, VI all pass through it — damage causes a complete ophthalmoplegia + forehead anesthesia
CN V has 3 branches exiting through 3 separate foramina (cribriform → no; superior orbital fissure, foramen rotundum, foramen ovale)
CN VII travels the longest intracranial bony canal — enters at the internal acoustic meatus and exits at the stylomastoid foramen through the facial canal in the temporal bone
Jugular foramen is the busiest posterior fossa opening: CN IX, X, and XI plus the internal jugular vein
CN VIII never leaves the skull to supply a peripheral structure directly — it terminates in the cochlea and vestibular apparatus
CN XI is unique: its spinal roots ascend through the foramen magnum before exiting via the jugular foramen

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