Skull Foramina

Posterior Cranial Fossa

Aperture	Bone(s) Involved	Structures Transmitted
condyloid canal	occipital	Emissary vein
foramen magnum *	occipital	spinal cord; spinal root of XI; vertebral artery and vein; anterior and posterior spinal artery and vein
hypoglossal canal *	occipital	XII, meningeal branch of ascending pharyngeal artery
internal auditory canal *	temporal	C.N. VII, VIII
jugular foramen *	occipital, temporal	C.N. IX, X, XI; internal jugular vein, inferior petrosal sinus
mastoid cannaliculus	temporal	auricular branch of vagus
mastoid foramen	temporal	emissary vein, meningeal branch of occipital artery
tympanomastoid fissure	temporal	auricular branch of vagus, fibers of C.N. IX and VII

Middle Cranial Fossa

accessory hiatus (innominate cannaliculus)	temporal	lesser petrosal nerve
foramen lacerum *	sphenoid, temporal, and occipital	filled with hyaline cartilage; traversed by meningeal branch of ascending pharyngeal artery, emissary veins passing from cavernous sinus to pharyngeal venous plexus
foramen rotundum *	sphenoid	C.N. V²
foramen spinosum *	sphenoid	middle meningeal artery, vein and sympathetic plexus, recurrent branch of V³ (nervus spinosus) to dura mater
formen ovale *	sphenoid	C.N. V³, lesser petrosal nerve (usually), accessory meningeal artery
hiatus of facial canal	temporal	greater petrosal nerve, superior tympanic branch of middle meningeal artery
optic canal *	sphenoid	C.N. II, ophthalmic artery, but NOT ophthalmic vein
superior orbital fissure *	sphenoid, frontal	C.N. III, IV, V¹, VI, superior ophthalmic veins
tympanic canaliculus	temporal	tympanic nerve (of C.N. IX), inferior tympanic branch of ascending pharyngeal artery

Anterior Cranial Fossa

cribriform plate *	ethmoid	olfactory nerves
foramen cecum	frontal, ethmoid	emissary vein from superior sagitttal sinus to veins of nasal cavity and frontal sinus

Exterior of Skull

alveolar canals	maxilla	posterior superior Alveolar artery, vein, and nerve
anterior ethmoid foramen (canal)	ethmoid, frontal	posterior ethmoid artery, vein, and nerve leaving orbit
Bony auditory tube *	temporal	Pharyngotympanic tube, tensor tympani muscle, external acoustic meatus to internal acoustic meatus
Carotid canal *	temporal	internal carotid artery with sympathetic plexus (internal carotid nerve), veins from cavernous sinus to pharyngeal plexus
Greater palatine foramen *	maxilla, palatine	descending palatine artery and vein, greater palatine nerve
Hypoglossal canal *	occipital	C.N. XII
Incisive foramen	maxilla	terminal branch of descending palatine artery and vein, nasopalatine nerve
Inferior Orbital fissure *	sphenoid, maxilla, palatine, zygomatic	C.N. V², zygomatic nerve, infraorbital artery and vein, veins connecting pterygoid plexus with inferior ophthalmic vein
infraorbital fissure *	maxilla	infraorbital branch C.N. V², infraorbital artery and vein
infraorbital foramen *	maxilla	infraorbital artery, vein, and nerve
jugular foramen *	occipital	C.N. IX, X, XI, inferior petrosal sinus, internal jugular vein
lesser palatine foramen *	palatine	lesser palatine artery and vein, lesser palatine nerves
mandibular foramen (dental foramen) *	mandible	inferior alveolar artery, vein, nerve
mental foramen *	mandible	mental artery, vein, and nerve
nasolacrimal canal *	lacrimal, maxilla	nasolacrimal duct
palatovaginal canal	pterygoid, palatine	pharyngeal branches of V² and maxillary artery
parietal foramen	parietal	emissary vein
petrotympanic fissure *	temporal	chorda tympani nerve
posterior ethmoid foramen (canal)	ethmoid, frontal	posterior ethmoid artery, vein, and nerve leaving orbit
pterygoid canal *	sphenoid	nerve of pterygoid canal (vidian nerve), which is combination of greater petrosal nerve (preganglionic parasymp.) and deep petrosal nerve (postganglionic symp.)
pterygomaxillary fissure *	maxilla, sphenoid	maxillary artery and accompanying veins
pteryogopalatine fossa *	sphenoid, palatine	Pterygopalatine ganglion, terminus maxillary artery
sphenopalatine foramen *	palatine, sphenoid	Sphenopalatine arteryandv.; posteriorsuperiornasal nerves (nasopalatine nerve is a branch)
stylomastoid foramen *	temporal	C.N. VII
supraorbital foramen or notch	frontal	Supraorbital artery, vein, and nerve
zygomaticofrontal foramen	zygomatic	Zygomaticofacial nerve
zygomatictemporal foramen	zygomatic	Zygomaticotemporal nerve

* clinically important; C.N. = Cranial Nerve, Innominate Canal = Carotid Canal

Sutures of the Skull

Coronal – between frontal bone and parietal bones

Sagittal – between two parietal bones

Squamous – between parietal bone and temporal bone (squamous part)

Lambdoid – between two parietal bones and occipital

Junctions

Lambda – intersection of lambdoid and sagittal sutures

Bregma – intersection of coronal and sagittal sutures

Pterion – forms an "H", junction between sphenoid bone and parietal bone is the middle of the "H"; where the parietal bone, frontal bone and sphenoid bone meet; also where the temporal, parietal, and sphenoid bones meet

Asterion – junction of occipital, parietal, and temporal bones.

Nasion – junction of frontal bone and two nasal bones.

Cranial Nerves and Cranial Exits

I: Olfactory – Cribriform Plate

II: Optic – Optic Canal

III: Oculomotor – Superior Orbital Fissure

IV: Trochlear – Superior Orbital Fissure

V: Trigeminal – three branches:

V1 (Opthalmic Nerve) – Superior Orbital Fissure

V2 (Maxillary Nerve) – Foramen Rotundum

V3 (Mandibular Nerve) – Foramen Ovale

VI: Abducens – Superior Orbital Fissure

VII: Facial – Internal Acoustic Meatus

VIII: Vestibulocochlear – Internal Acoustic Meatus

IX: Glossopharyngeal – Jugular Foramen

X: Vagus Nerve – Jugular Foramen

XI: Accessory – Jugular Foramen

XII: Hypoglossal – Hypoglossal Canal