Cranial Nerves Flashcards
Where are the cell bodies of the primary sensory neurons of the facial nerve located?
Geniculate ganglion
The smaller intermediate facial nerve carries taste sensory fibres and parasympathetic fibres. T/F?
True
While traversing the temporal bone within the geniculate ganglion the facial nerve gives rise to which other nerves?
Greater petrosal nerve
Nerve to stapedius
Chorda tympani nerve
What sensations are provided by Cn VIII?
Hearing and equilibrium
Where are the vestibular nuclei on CN VIII locates?
The junction of pins and medulla in the lateral part of forth ventricle
Where are the anterior and posterior cochleae nuclei of VIII located?
In the medulla
Where in the inner ear do the peripheral processes of neurons of the vestibular branch of CNVIII extend?
Utricle and saccule (linear acceleration) and Cristae of the ampullae of the semicircular canals (rotational acceleration)
Where in the inner ear do the process of the cochleae branch of CNVIII extend?
Cochlea
Within the internal acoustic meats, the two branches of CNVIII are accompanied by which other cranial nerve?
The facial nerve
Which eye muscles are innervated by CNIII?
superior, middle and inferior rectus
Inferior oblique
Which eye muscle is innervated by CNIV?
Superior oblique
Which eye muscle is innervated by CNVI?
Lateral rectus
What group of muscles are innervated by CN V?
Muscles of mastication
The muscles of mastication are innervated by CN V. What are the muscles of mastication?
Lateral and medial pterygoids
masseter
temporalis
Which nerve transmits sensory information from the anterior 1/3 of the tongue?
Facial nerve
Which nerve transmits sensory information from the posterior tongue?
Glossopharyngeal nerve
What group of muscles and what gland is innervated by CN IX?
Muscles of swallowing
Parotid salivary gland
Which cranial nerve provides parasympathetic innervation to the sublingual and submandibular salivary glands?
Facial nerve
Which cranial nerve innervates the muscles of the larynx?
Vagus nerve
Which cranial nerve has a spinal root?
CN XI
What muscles are innervated by CN XI?
Sternocleidoimastoid
Trapezius
Which nerve provides motor innervation of the tongue?
CN XII
Bilateral loss of smelling is usually associated with deficits in what other sensory function?
Taste
How can CNI be tested?
Ask about recent changes in smelling
test patients ability to smell substance such as coffee or cinnamon in each nostril
How can CNII be tested?
By wiggling a finger in each of the four quadrants of vision and getting the patient to tell you which finger you are wiggling
How can CN III, IV and VI be tested?
ask patient to follow your finger as you move it in a ‘H’ position through the four quadrants
then ask patient to keep head still and move eyes up, down, left and right
check for doll’s eye
How can CN V be tested?
Normal sensory testing using light touch and pin prick on forehead, cheeks bone and chin on both sides
Get the patient to clench neither teeth and palpate the masters
How can CN VII be tested?
Ask patient to Elevate eyebrows, close eyes tightly and resist you opening them, blow out their cheeks with air, purse lips tightly together, smile
In which hearing test is a vibrating tuning fork placed on the mastoid process to test bone conduction and then compared with air conduction with tuning fork placed near to the ear?
Rhinne’s test
Air conductance should be louder than bone conductance. In what type of hearing loss will the opposite be true?
Conductive hearing loss
In Weber’s test a vibrating tuning fork is placed at the midline over the vertex and the patient is asked whether or not the sound is perceived equally in both ears. Sound will be heard louder in the affected ear in what type of deafness?
Conductive deafness
In Weber’s test a vibrating tuning fork is placed at the midline over the vertex and the patient is asked whether or not the sound is perceived equally in both ears. Sound will be heard louder in the unaffected ear in what type of deafness?
Perceptive deafness
Which reflex is tested to investigate CN IX?
The gag reflex
How is CN X tested?
Ask the patient to speak and to cough
How is CN XI tested?
Ask patient to shrug their shoulders first without then with resistance - tests trapezius
ask patient to rotate their head to the contralateral side against the resistant of your hand - tests sternocleidomastoid
Which cranial nerve are you testing by asking the patient to stick out their tongue and wiggle it from side to side?
CN XII
Which nerve provides somatosensory innervation to the nasal cavity?
Trigeminal nerve
which intrinsic eye muscles are innervated by the oculomotor nerve?
Sphincter pupillae
Ciliary muscle
Where do CN III, IV and VI enter the orbit?
Superior orbital fissure
Which cranial nerves are involved in the corneal reflex?
Trigeminal nerve (ophthalmic division) - sensory afferent facial nerve to orbicularis occult - motor efferent
Which nerves are involved in the gag reflex?
Afferent - glossopharyngeal nerve
Efferent - vagus nerve
Shingles is caused by reactivate of which virus?
Varicella-zoster virus
Loss of function of CN 9, 10 and 11 can be cause by anything which compresses the jugular foramen. What is the most common cause of this?
Paraganglioma
CSF contains glucose. T/F?
True
The level of what substance can be checked to test whether a clear fluid from the nose is CSF as this substance is only present in CSF?
Beta-2-transferrin
Medical causes of CN III palsy such as diabetes mellitus will often spare the pupil. T/F?
True - whereas ‘surgical’ causes such as nerve lesion will present with dilated pupil
