Cranial Fossae

Question 1

What is the posterior boundary of the anterior cranial fossa?

Answer 1

line drawn along the lesser wing of the sphenoid, anterior clinoid processes, & sphenoidal jugum

Question 2

What passes through the cribriform plate?

Answer 2

fila olfactoria of cranial nerve I, the olfactory nerve

Question 3

An emissary vein leaves the anterior cranial fossa via what opening?

Answer 3

foramen cecum

Question 4

What is the posterior boundary of the middle cranial fossa?

Answer 4

superior border of petrous part of temporal bone, posterior cloned processes & dorsal sella of sphenoid bone

Question 5

What are the parts of the sella turcica?

Answer 5

anterior clinoid processes, sphenoidal jugum, posterior clinoid processes, dorsum sella, & hypophysial fossa of sphenoid bone

Question 6

What forms the roof of the sella turcica?

Answer 6

diaphragma sella

Question 7

What are the contents of the optic canal?

Answer 7

optic nerve and ophthalmic artery

Question 8

What are the contents of the superior orbital fissure?

Answer 8

ophthalmic veins, oculomotor nerve, trochlear nerve, ophthalmic division of the trigeminal nerve, abducent nerve

Question 9

What is unique about the ophthalmic artery and veins?

Answer 9

unlike other artery-vein combinations they will not share the same opening. The ophthalmic artery is in the optic canal, ophthalmic veins are in the superior orbital fissure

Question 10

What are the contents of the foramen rotundum?

Answer 10

maxillary division of the trigeminal nerve (cranial nerve Vb)

Question 11

What are the contents of the foramen ovale?

Answer 11

mandibular division of the trigeminal nerve (Vc) and lesser petrosal branch of the glossopharyngeal nerve

Question 12

What are the contents of the foramen spinosum?

Answer 12

nervus spinous from the mandibular division of the trigeminal nerve and the middle meningeal artery

Question 13

What forms the vidian nerve/nerve of the pterygoid canal?

Answer 13

greater (superficial) petrosal nerve from the facial nerve and the deep petrosal nerve from the carotid sympathetic nerve plexus

Question 14

What are the contents of the hiatus for the lesser petrosal nerve?

Answer 14

lesser petrosal nerve, a branch of the tympanic plexus from the glossopharyngeal nerve

Question 15

How will the lesser petrosal nerve typically exit the middle cranial fossa?

Answer 15

the foramen ovale

Question 16

What forms the roof of the posterior cranial fossa?

Answer 16

tentorium cerebelli

Question 17

What part of the cerebrum occupies the posterior cranial fossa?

Answer 17

none; the tantrum cerebral separates the cerebrum into a space above the posterior cranial fossa

Question 18

What are the contents of the internal acoustic meatus?

Answer 18

cranial nerves VII (facial) and VIII (vestibulocochlear/auditory nerve), the nervus intermedius/nerve of Wrisberg/sensory root of VII and the motor root of VII, the vestibular and cochlear roots of VIII and the internal auditory/internal labyrinthine artery and vein

Question 19

What are the contents of the jugular foramen?

Answer 19

the jugular bulb, the inferior petrosal sinus, the tympanic body/glomus or jugular body/glomus, cranial nerves IX (glossopharyngeal), X (vagus), and XI (spinal accessory)

Question 20

What is the name of the venous expansion between the sigmoid dural venous sinus and the internal jugular vein?

Answer 20

the jugular bulb

Question 21

What is the function of the tympanic body/glomus?

Answer 21

a chemoreceptive organ which monitors hypoxia, hypercapnia, and increases in the hydrogen ion