Auditory System Clinical Application

Question 1

The auditory pathway begins with first-order neurons with cell bodies in __________ and axons in ___________ nerve. They synapse in the _________ nuclei

Answer 1

spiral ganglia, vetibulocochlear nerve, ipsilateral cochlear nuclei

Question 2

Second order neurons in the auditory pathway have their cell bodies in the _______ nuclei and their axons in the ________ and _______ of the pons. These axons eventually reach the ________ in the midbrain.

Answer 2

cochlear nuclei, trapezoid, lateral lemniscus, inferior colliculus

Question 3

The step in the auditory pathway just before the information reaches the thalamus is axons in the ________ of the caudal midbrain travel to their cell bodies in the same structre. Axons from these neurons then travel through the ________ of the _________ and synapse finally in the ______ of the thalamus.

Answer 3

inferior colliculus, brachium, inferior colliculus, MGN

Question 4

Thalamic neurons of the auditory pathway have their cell bodies in the ______ of the thalamus and their axons travel in the ________ to synapse in the __________

Answer 4

MGN, auditory radiation, primary auditory cortex

Question 5

The _________ decussates but does not contribute to bilateralism of the auditory pathway

Answer 5

posterior acoustic stria

Question 6

The 3 structures which contribute to bilateralism in the auditory pathway are:

Answer 6

commissure of inferior colliculus, commissure of lateral lemniscus, trapezoid body

Question 7

The 3 structures that contribute to bilateralism in the auditory pathway and prevent loss of hearing with lesions _______ to ________ nuclei are found in the _______ pons, and the commissure of inferior colliculus is found in the _______ midbrain

Answer 7

proximal, cochlear nuclei, middle, posterior

Question 8

The ________ artery from the _______ artery supplies the inner ear and cochlear nuclei

Answer 8

labyrinthine artery, AICA

Question 9

The _________ branch of the ________ artery supplies the inferior colliculus

Answer 9

quadrigeminal, superior cerebellar artery (SCA)

Question 10

The thalamogeniculate artery supplies the _____.

The _________ artery supplies the primary auditory cortex and auditory radiation.

Answer 10

MGN, MCA (inferior trunk)

Question 11

A patient presents to the clinic with tinnitus in the right ear and almost total deafness in that ear. Neither air or bone conduction of sound is effected.
What kind of deafness is this?

Answer 11

sensorineural deafness

Question 12

________ deafness can be caused by a lesion to the hair cells, organ of corti, spiral ganglion, CN VIII, cochlear nuclei, or the cochlea itself.

Answer 12

sensorineural deafness

Question 13

A patient presents with otitis media in the left ear, an infection and inflammation of the cochlea. She has some form of deafness. What kind of deafness is this?

Answer 13

sensorineural deafness

Question 14

A patient has damage to the superior olivary nuclei. What kind of deafness do they likely have?

Answer 14

central deafness

Question 15

A patient presents with difficulty localizing or interpreting sounds with no loss of hearing. Air and bone conduction of sound is unaffected. What kind of deafness is this?

Answer 15

central deafness

Question 16

________ deafness is caused by lesion to one of the following:
lateral lemniscus, inferior colliculus, MGN, auditory radiation, auditory cortex

Answer 16

central deafness

Question 17

A patient presents with partial left-sided deafness. Bone conduction of sound is unaffected but air conduction is diminished to the left side. No other neurological signs are found. What is the type of deafness?

Answer 17

conduction deafness

Question 18

________ deafness is caused by one of the following:
inflammation/infection of EAM (otitis externa), excessive ear wax in EAM, inflammation or trauma of tympanic membrane, inflammation/infection of middle ear (otitis media), damage to middle ear bones, tissue overgrowth and fixation of stapes to oval window (otosclerosis)

Answer 18

conduction deafness

Question 19

Tissue overgrowth that results in the fixation of the stapes to the oval window is referred to as _______, and is a cause of ______ deafness

Answer 19

otosclerosis, conduction deafness

Question 20

If the neural pathway of auditory conduction is disrupted at or before the cochlear nuclei, this is _________ deafness.

Answer 20

sensorineural deafness

Question 21

With _______ deafness, the vibration during the Weber test is perceived best on the normal side since the other side has damaged hair cells, CN VIII, or cochlear nuclei.

Answer 21

sensorineural deafness

Question 22

With conduction deafness the vibration during Weber test is perceived best on the side with _________________ since this decreases the phase interference of air and bone conduction.

Answer 22

diminished air conduction

Question 23

During the rinne test, a person with _______ deafness will be unable to perceive any sound waves

Answer 23

sensorineural deafness

Question 24

During the Rinne test, a person with ________ deafness will perceive bone conduction time as equal to or greater than air conduction time.

Answer 24

conduction deafness

Question 25

With __________, a patient will perceive air conduction time as twice as long as bone conduction time during the rinne test

Answer 25

central deafness

Question 26

A patient presents with a form of hearing loss. The Weber test reveals that the patient perceives sounds as louder on the right, and the Rinne test finds that air conduction is greater than bone conduction on the right. What is the diagnosis?

Answer 26

left side nerve deafness

Question 27

A patient has a Weber test that is left-sided, and a Rinne test that shows AC>BC on the left. What is the diagnosis?

Answer 27

right side nerve deafness

Question 28

A patient presents with almost complete hearing loss to the left side with a Weber test that is greater on the right and a Rinne test that shows AC>BC on the right. An angiogram shows occlusion of an artery. What artery is occluded?

Answer 28

labyrinthine artery from AICA —> damaged inner ear and cochlear nuclei

Question 29

Central deafness can be caused by occlusion of any of the following 4 arteries:

Answer 29

circumferential basilar branches, quadrigeminal branches of SCA, MCA inferior trunk, thalamogeniculate artery

Question 30

Occlusion of the labyrinthine artery causes ________ and affects the following 7 structures in the lateral caudal pons:

Answer 30

ALS, spinal trigeminal nucleus and tract, vestibular nuclei, MCP and lateral cerebellum, hypothalamospinal tract, facial nucleus and nerve, cochlear nuclei

Question 31

A patient presents with left-sided hemianalgesia, right-sided hemianalgesia of the face, left-sided nystagmus, nausea, vomiting, vertigo, ataxia, right-sided Horner syndrome, right-sided facial hemiparesis, and right-sided nerve deafness. What artery is occluded?

Answer 31

AICA (including labyrinthine artery)

Question 32

A patient presents to the emergency department complaining of ptosis, myosis, and anhydrosis of the left face. He also has left-sided hemianalgesia of the body and right-sided hemianalgesia of the face. Further evaluation determines he has right-sided nerve deafness as well as left-sided nystagmus. What artery is occluded?

Answer 32

AICA (including labyrinthine artery)

Question 33

They key structures damaged in occlusion of the _______ artery are facial nucleus and nerve, as well as cochlear nuclei. The key findings are ipsilateral facial hemiparesis and ipsilateral nerve deafness.

Answer 33

AICA

Question 34

The key findings in lateral medullary syndrome are _____________ and _________.
The key structure damaged is the _________.

Answer 34

contralateral deviation of the uvula, hoarseness, nucleus ambiguous

Question 35

Occlusion of _______ affects these 5 structures:

trapezoid, medial lemniscus, corticospinal tract axons, corticonuclear tract axons, abducens nucleus and nerve

Answer 35

paramedian branches of basilar artery

Question 36

Occlusion of the ________ artery results in difficulty localizing and interpreting sounds, contralateral loss of vibration sense, contralateral hemiplegia or hemiparesis, UMN signs for corticonuclear tract in medulla, contralateral gaze palsy

Answer 36

paramedian branches of basilar artery

Question 37

Occlusion of the _______ artery results in damage to these 6 structures:
Inferior colliculus, ALS, medial lemniscus, anterior trigeminothalamic tract, crus cerebri, substantia nigra

Answer 37

quadrigeminal branch of superior cerebellar artery

Question 38

Occlusion of the _______ artery results in these 4 clinical signs:
difficulty localizing and interpreting sounds; contralateral hemianesthesia of UE, LE, and face; possible contralateral plegia or paresis of LE; contralateral tremor

Answer 38

quadrigeminal branch of the superior cerebellar artery

Question 39

Occlusion of the _____ artery results in damage to these 3 structures:
MGN, LGN, VPL/VPM

Answer 39

thalamogeniculate artery

Question 40

Occlusion of the _______ artery results in these 4 clinical signs:
difficulty localizing and interpreting sounds; contralateral homonymous hemianopia; contralateral hemianesthesia of UE, LE, and face; may develop thalamic pain syndrome

Answer 40

thalamogeniculate artery

Question 41

Occlusion of the _______ artery results in contralateral hemiparesis or hemiplegia of the UE, LE, and lower face; contralateral hemianesthesia of the UE, LE, and face; and difficulty localizing and interpreting sounds

Answer 41

lenticulostriate arteries of the MCA

Question 42

Occlusion of the _______ artery results in contralateral paresis or plegia of the UE and lower face; contralateral anesthesia of the UE and face; and contralateral gaze palsy

Answer 42

MCA superior trunk

Question 43

Occlusion of the _____ artery results in contralateral superior quadrantanopia and difficulty localizing and interpreting sounds

Answer 43

MCA inferior trunk

Question 44

Occlusion of _______ artery results in contralateral paresis or plegia of UE, LE, and lower face; contralateral anesthesia of UE and face; contralateral gaze palsy; contralateral superior quadrantanopia; difficulty localizing and interpreting sounds

Answer 44

MCA distal stem

Question 45

Occlusion of _____ artery results in contralateral hemiparesis or hemiplegia of UE, LE, and lower face; contralateral hemianesthesia of UE, LE, and face; contralateral gaze palsy; contralateral homonymous hemianopia; difficulty localizing and interpreting sounds

Answer 45

MCA proximal stem