Anatomy: Cranial Nerves

Question 1

list the cranial nerves

Answer 1

CNI olfactory
CNII optic
CNII oculomotor
CNIV trochlear
CNV trigeminal 
CNVI abducens
CNVII facial
CNVIII vestibulocochlear
CNIX glossopharyngeal
CNX vagus
CNXI spinal accessory
CNXII hypoglossal

Question 2

saying to remember modality of the cranial nerves

Answer 2

some say marry money but my brother says big brains matter more

Question 3

exit of CNI

Answer 3

cribriform plate of the ethmoid bone

Question 4

exit of CNII

Answer 4

optic canal

Question 5

which cranial nerves exit the superior orbital fissure?

Answer 5

CNIII
CNIV
CNV1
CNVI

Question 6

which cranial nerve exits the foramen rotundum?

Answer 6

CNV2

Question 7

which cranial nerve exits the foramen ovale

Answer 7

CNV3

Question 8

which cranial nerves exit the internal acoustic meatus?

Answer 8

CNVII

CNVIII

Question 9

which cranial nerves exit the jugular foramen?

Answer 9

CNIX
CNX
CNXI

Question 10

which cranial nerve exits the hypoglossal canal

Answer 10

CNXII

Question 11

exit of all cranial nerves

Answer 11

all anterior except CNIV which is posterior and VIII lateral

Question 12

describe CNI

Answer 12

nerve is made up of little filaments that extend from the olfactory bulb and pass through the cribriform plate

Question 13

where is the primary olfactory cortex located?

Answer 13

posterior portion of the frontal lobe and medial temporal lobe

Question 14

role of oculomotor

Answer 14

somatic motor to levator papillae superioris, SR, MR, IR and IO
parasympathetic to sphincter pupillae and ciliary muscle

Question 15

role of trochlear

Answer 15

somatic motor to SO

Question 16

role of abducens

Answer 16

somatic motor to LR

Question 17

role of spinal accessory

Answer 17

somatic motor to trapezius and sternocleidomastoid

Question 18

role of hypoglossal

Answer 18

somatic motor to intrinsic tongue (genioglossus, hyoglossus, styloglossus)

Question 19

clinical testing of hypoglossal

Answer 19

ask patient to stick tongue out

unilateral pathology will point towards side of injured nerve

Question 20

three divisions of CNV

Answer 20

ophthalmic
maxillary
mandibular

Question 21

functions of CNV

Answer 21

• somatosensory to face
• proprioception associated with chewing (TMJ, muscles of mastication, teeth)
• motor to muscles of mastication (masseter, temporalis, medial and lateral pterygoid), tensor tympani, mylohyoid, anterior belly of digastric and tensor veli palatini

Question 22

functions of CNVII

Answer 22

• motor to muscles of facial expression and stapedius
• parasympathetic to pterygopalatine and submandibular ganglia
• taste to anterior 2/3rd tongue
• somatosensory to small region of the ear

Question 23

nucleus to ganglia

Answer 23

salivatory nucelus

Question 24

nucleus for taste

Answer 24

solitary nucleus

Question 25

functions of CNIX

Answer 25

- sense pain and temperature from posterior tongue, pharyngotympanic tube, upper pharynx - visceral afferent to carotid sinus baroreceptor and carotid body chemoreceptor - taste to posterior 1/3rd of tongue - parasympathetic to otic ganglion - motor to stylopharyngeus

Question 26

where is the carotid sinus

Answer 26

base of the ICA

Question 27

functions of the vagus nerve

Answer 27

- sense pain and temperature from pharynx, larynx, trachea, oesophagus and thoracic/abdominal viscera - taste in epiglottis - parasympathetic to ganglia of thoracic and abdominal viscera - motor to striated muscle of pharynx and larynx

Question 28

clinical test of CNX

Answer 28

ask patient to say ah and uvula should lift straight up in midline unilateral pathology will pull away from non-functioning side

Question 29

route of the spinal accessory nerve

Answer 29

ascends through foramen magnum then travels towards jugular foramen in posterior cranial fossa

Question 30

what structure has a problem if splutter on swallowing water?

Answer 30

larynx

Question 31

what structure has a problem if hoarseness present

Answer 31

abnormal function of larynx muscles