Cranial nerves

Question 1

from which pharyngeal arch is the trigeminal nerve derived and what is its motor function?

Answer 1

it is derived from the first pharyngeal arch and innervates the muscles of mastication and anterior belly of digastric as well as the tensor tympani

Question 2

through which cranial foramen does the first division of the trigeminal nerve pass through?

Answer 2

superior orbital fissure

Question 3

What passes through the foramen caecum and where is it found?

Answer 3

anterior cranial fossa- emissary veins to nasal cavity

Question 4

Through what do the olfactory nerves pass through?

Answer 4

foramina of the cribriform plate of the ethmoid bone

Question 5

What foramen does the optic nerve pass through and what accompanies it?

Answer 5

optic canal, ophthalmic artery

Question 6

What foramina are found in the middle cranial fossa (anterior to posterior and what passes through each)

Answer 6

Superior orbital fissure- CN III,IV,opthalmic nerve and VI, opthalmic veins
foramen rotundum- maxillary nerve
foramen lacerum- internal carotid runs along it
foramen ovale- mandibular nerve
foramen spinosum- middle meningeal artery
hiatus for greater petrosal nerve- greater petrosal nerve
hiatus for lesser petrosal nerve- lesser petrosal nerve

Question 7

What foramina are found in the posterior cranial fossa and what do they conduct?

Answer 7

internal acoustic meatus- facial nerve, labyrinthine artery and vestibulocochlear nerve
carotid canal- internal carotid artery
jugular foramen- CN IX,X,XI, internal jugular vein (inferior petrosal sinus, sigmoid sinus)
foramen magnum- spinal cord/brainstem, vertebral artery, spinal roots of the accessory nerve, meninges
hypoglossal canal- hypoglossal nerve
condylar canal- emissary vein

Question 8

Which nerve innervates the laryngeal muscles, taste from the epiglottis, aortic bodies, tone to the heart and GIT, muscles of the pharynx and sensation to the exterior of the external auditory meatus?

Answer 8

Vagus nerve (recurrent laryngeal doing all but cricothyroid muscle in the larynx)

Question 9

What structures run along the cavernous sinus?

Answer 9

internal carotid
CNIII,IV,first and second division of V, VI
petrosal sinuses and sigmoid sinus drain into it

Question 10

What structures does the glossopharyngeal nerve innervate?

Answer 10

posterior third of tongue for taste
sensation and motor innervation of pharynx
parasympathetic innervation of the parotid gland
sensation of the tongue
stylopharyngeus- elevate the soft palate
carotid sinus/body

Question 11

What does the facial nerve innervate?

Answer 11

muscles of facial expression
stapedius
anterior 2/3 taste of tongue (chorda tympani)
sensation posterior ear
pterygopalatine ganglion-lacrimal glands
submandibular ganglion- submandibular and sublingual glands