Cranial Nerves/Intracranial Vault Flashcards
CN 1
Olfactory nerve: Sensory
CN II
Optic Nerve: Sensory
CN III
Oculomotor : Motor
all eye muscles except those suppled by IV and V
CN IV
Trochlear : Motor
superior oblique muscle
CN V
Trigeminal : Both
Sensory = face, sinuses, teeth, etc.
Motor = muscles of mastication
CN VI
Abducent : Motor
external rectus muscle
CN VII
Facial : Motor
muscles of face
CN VIII
Vestibulocochlear (acoustic) : Sensory
inner ear
CN IX
Glossopharyngeal : Both
Motor = pharyngeal musculature
Sensory = posterior part of tongue, tonsil and pharynx
CN X
Vagus : Both
Motor = heart, lungs, bronchi, GI,
Sensory = heart , lungs, trachea, larynx, pharynx, GI, external ear
CN XI
Accessory : Motor
sternocleidomastoid and trapezium muscle
CN XII
Hypoglossal : Motor
muscles of the tongue
Facial Nerve (VII) innervates the….
Orbicularis Oculi
Frequently monitored during surgery:
Parotidectomy, acoustic neuroma, cochlear implant
Facial nerve (VII)
Sensory innervation to the baroreceptors of the carotid sinus:
Can cause bradycardia and hypotension during CEA
Cranial Nerve IX (Glossopharyngeal)
Cranial Nerve IX (Glossopharyngeal)
Motor innervation of the ________
pharynx (swallowing)
Cranial Nerve IX (Glossopharyngeal)
Sensory innervation to _______ and ________.
posterior oral mucosa (gag reflex)
chemoreceptors of the carotid body
Cranial Nerve IX (Glossopharyngeal):
Provides parasympathetic innervation to the ______ gland.
parotid gland
Injury to the ____ or ____ may occur during thyroid surgeries.
SLN or RLN
Internal branch of SLN =
sensory
External branch of the SLN
motor
cricothyroid muscles
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.
The SLN (external branch)
RLN innervation:
innervates all of the intrinsic muscles of the larynx except for the cricothyroid.
A unilateral RLN injury produces:
abductor vocal cord paralysis (posterior cricoarytenoid muscle), so the affected cord assumes a paramedian position which causes postoperative hoarseness.
Bilateral vocal cord paralysis produces:
partial vs. complete airway obstruction (SERIOUS!!!)
Symptoms include respiratory distress with stridor. The situation often necessitates emergent reintubation or tracheostomy.
Cranial Nerve X (Vagus): Lungs
Parasympathetic stimulation within the pulmonary plexuses causes vasodilation and bronchoconstriction.
Cranial Nerve X (Vagus): Heart
Cardiac branches convey parasympathetic innervation to the SA and AV nodes of the heart. Vagal stimulation reduces heart rate and is constantly active.
Cranial Nerve X (Vagus): GI system
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
