Cranial Nerves Flashcards
List the Cranial Nerves
1 Olfactory
2 Optic
3 Oculomotor
4 Trochlear
5 Trigeminal
6 Abducens
7 Facial,
8 Vestibulocochlear
9 Glossopharyngeal
10 Vagus
11 Accessory
12 Hypoglossal
Use this mnemonic to help you remember the order: On Old Olympus Towering Tops A Fat Vested German Viewed A Hop
Name, Function (Sensory, Motor, Both), and Monitoring Details for CN I
Olfactory (S)
Sense of Smell
Cannot be monitored
Name, Function (Sensory, Motor, Both), and Monitoring Details for CN II
Optic (S)
Vision
Visual Evoked Potentials
Name, Function (Sensory, Motor, Both), and Monitoring Details for CN III
Oculomotor (M)
Eye Movement, Inferior Rectus (Under eye)
EMG/tcMEP
Name, Function (Sensory, Motor, Both), and Monitoring Details for CN IV
Trochlear (M)
Eye Movement, Superior Oblique Muscle (Over eye)
EMG/tcMEP
Name, Function (Sensory, Motor, Both), and Monitoring Details for CN V
Trigeminal (B)
Three divisions of nerve: V1 Ophthalmic, V2 Maxillary, V3 Mandibular
Motor portion: Muscles of Mastication
Sensory portion: Convey Sensations of Touch, Pain, and Temperature
EMG, tcMEP: Masseter and Temporalis
Name, Function (Sensory, Motor, Both), and Monitoring Details for CN VI
Abducens (M)
Eye Movement, Lateral Rectus (Lateral to eye)
EMG/tcMEP
Name, Function (Sensory, Motor, Both), and Monitoring Details for CN VII
Facial (B)
Five Branches: Temporal, Zygomatic, Buccal, Marginal Mandibular, Cervical
(Use this mnemonic to help you remember: To Zanzibar By Motor Car)
Motor portion: Facial Expressions
Sensory portion: Anterior 2/3 of Tongue, Floor of Mouth/Anterior Palate
EMG/tcMEP
What are the Five Branches of CN VII and what muscles are monitored for each branch?
Temporal Branch / Frontalis Muscle
Zygomatic Branch / Orbicularis Oculi Muscle
Buccal Branch / Orbicularis Oris Muscle
Marginal Mandibular Branch / Mentalis Muscle
Cervical / Platysma Muscle
Note: Branches Pass through Parotid Gland
Name, Function (Sensory, Motor, Both), and Monitoring Details for CN VIII
Vestibulocochlear (S)
Balance, Maintenance of Body Position and Proprioception (Vestibular)
Sense of Hearing (Cochlear),
BAEP
Name, Function (Sensory, Motor, Both), and Monitoring Details for CN IX
Glossopharyngeal (B)
Motor portion: Assist in swallowing
Sensory portion: Posterior 1/3 tongue
Soft Palate
EMG/tcMEP
Name, Function (Sensory, Motor, Both), and Monitoring Details for CN X
Vagus (B)
Motor portion: Pharynx and Larynx control
Sensory portion: Sensory function of larynx
EMG/tcMEP Vocalis via Recurrent Laryngeal Nerve Monitoring
Name, Function (Sensory, Motor, Both), and Monitoring Details for CN XI
Accessory (M)
Shoulder Movement, Trapezius and Sternocleidomastoid
EMG/tcMEP
Name, Function (Sensory, Motor, Both), and Monitoring Details for CN XII
Hypoglossal (M)
Speech and Swallowing
Lateral aspect of the anterior 1/3 of the Ipsilateral Tongue
EMG/tcMEP
A cavernous sinus surgery involves what cranial nerves?
CN III (Oculomotor) CN IV (Trochlear) CN VI (Abducens)
All of these nerves pass through the cavernous sinus.
A skull base (clival) surgery involves what cranial nerves?
CN V (Trigeminal) CN VII (Facial) CN VIII (Vestibulocochlear/Auditory)
(Skull Base surgery)
Clivus = Bone at base of skull, tumors sometimes grow here
A Microvascular Decompression surgery for treatment of Trigeminal Neuralgia involves what cranial nerves?
CN V (Trigeminal) CN VII (Facial) CN VIII (Auditory)
MVD involves opening the skull (craniotomy) and inserting a sponge between the nerve and offending artery triggering the pain signals.
Cerebellopontine (CP) Angle (e.g. acoustic neuroma) lesion would affect what CN?
CN V (Trigeminal) CN VII (Facial) CN VIII (Auditory)
(CN V-XII if lesion is large enough)
What is Tic Douloureux?
We know this as Trigeminal Neuralgia. It comes from the French phrase Tic Douloureux which literally means “a painful tic”
Compression of CN V usually caused by Superior Cerebellar Artery (SCA) which results in intolerable facial pain
Monitored: CN V (Trigeminal) CN VII (Facial) CN VIII (Auditory)
What is Hemifacial Spasm?
Hemifacial spasm is a nervous system disorder in which the muscles on one side of your face twitch involuntarily. Hemifacial spasm is most often caused by a blood vessel touching or pulsating against a facial nerve. It may also be caused by a facial nerve injury or a tumor.
What is Glossopharyngeal Neuralgia?
Irritation of the ninth cranial nerve causing pain at the back of the throat (rare)
What does the Pons control?
The pons relays information about motor function, sensation, eye movement, hearing, taste, and more.
The middle four cranial nerves originate from the pons:
- trigeminal nerve (CN V)
- abducens nerve (CN VI)
- facial nerve (CN VII)
- vestibulocochlear nerve (CN VIII)
What does the Medulla control?
The medulla oblongata plays a critical role in transmitting signals between the spinal cord and the higher parts of the brain and in controlling autonomic activities, such as heartbeat and respiration.
The final four cranial nerves originate from the medulla oblongata:
- glossopharyngeal nerve (CN IX)
- vagus nerve (CN X)
- accessory nerve (CN XI)
- hypoglossal nerve (CN XII)
