Cranial Nerves/Intracranial Vault

Question 1

CN 1

Answer 1

Olfactory nerve: Sensory

Question 2

CN II

Answer 2

Optic Nerve: Sensory

Question 3

CN III

Answer 3

Oculomotor : Motor
all eye muscles except those suppled by IV and V

Question 4

CN IV

Answer 4

Trochlear : Motor
superior oblique muscle

Question 5

CN V

Answer 5

Trigeminal : Both

Sensory = face, sinuses, teeth, etc.
Motor = muscles of mastication

Question 6

CN VI

Answer 6

Abducent : Motor
external rectus muscle

Question 7

CN VII

Answer 7

Facial : Motor
muscles of face

Question 8

CN VIII

Answer 8

Vestibulocochlear (acoustic) : Sensory
inner ear

Question 9

CN IX

Answer 9

Glossopharyngeal : Both

Motor = pharyngeal musculature
Sensory = posterior part of tongue, tonsil and pharynx

Question 10

CN X

Answer 10

Vagus : Both

Motor = heart, lungs, bronchi, GI,
Sensory = heart , lungs, trachea, larynx, pharynx, GI, external ear

Question 11

CN XI

Answer 11

Accessory : Motor
sternocleidomastoid and trapezium muscle

Question 12

CN XII

Answer 12

Hypoglossal : Motor
muscles of the tongue

Question 13

Facial Nerve (VII) innervates the….

Answer 13

Orbicularis Oculi

Question 14

Frequently monitored during surgery:
Parotidectomy, acoustic neuroma, cochlear implant

Answer 14

Facial nerve (VII)

Question 15

Sensory innervation to the baroreceptors of the carotid sinus:
Can cause bradycardia and hypotension during CEA

Answer 15

Cranial Nerve IX (Glossopharyngeal)

Question 16

Cranial Nerve IX (Glossopharyngeal)
Motor innervation of the ________

Answer 16

pharynx (swallowing)

Question 17

Cranial Nerve IX (Glossopharyngeal)
Sensory innervation to _______ and ________.

Answer 17

posterior oral mucosa (gag reflex)
chemoreceptors of the carotid body

Question 18

Cranial Nerve IX (Glossopharyngeal):
Provides parasympathetic innervation to the ______ gland.

Answer 18

parotid gland

Question 19

Injury to the ____ or ____ may occur during thyroid surgeries.

Answer 19

SLN or RLN

Question 20

Internal branch of SLN =

Answer 20

sensory

Question 21

External branch of the SLN

Answer 21

motor
cricothyroid muscles

Question 22

The _________ innervates the cricothyroid muscle, which tenses and adducts the vocal cords. Injury to the nerve can produce changes in voice quality, but is generally not dangerous.

Answer 22

The SLN (external branch)

Question 23

RLN innervation:

Answer 23

innervates all of the intrinsic muscles of the larynx except for the cricothyroid.

Question 24

A unilateral RLN injury produces:

Answer 24

abductor vocal cord paralysis (posterior cricoarytenoid muscle), so the affected cord assumes a paramedian position which causes postoperative hoarseness.

Question 25

Bilateral vocal cord paralysis produces:

Answer 25

partial vs. complete airway obstruction (SERIOUS!!!)

Symptoms include respiratory distress with stridor. The situation often necessitates emergent reintubation or tracheostomy.

Question 26

Cranial Nerve X (Vagus): Lungs

Answer 26

Parasympathetic stimulation within the pulmonary plexuses causes vasodilation and bronchoconstriction.

Question 27

Cranial Nerve X (Vagus): Heart

Answer 27

Cardiac branches convey parasympathetic innervation to the SA and AV nodes of the heart. Vagal stimulation reduces heart rate and is constantly active.

Question 28

Cranial Nerve X (Vagus): GI system

Answer 28

Provides parasympathetic innervation to the majority of the abdominal organs. The function of the Vagus Nerve is to stimulate smooth muscle contraction and glandular secretions in these organs