auditory function and balance

Question 1

effect of unilateral lesion in vestibular system

Answer 1

could be organ or nerve, so no resting discharge from one side of vestibular system, so interprets as movement in direction of no resting discharge, so eyes move to left; vision recorrects -> constant cycle of slow brainstem movement and fast central compensation

Question 2

8 methods of diagnosing unilateral lesion in vestibular system

Answer 2

anamnesis, cranial nerves, balance and gait assessment, cerebellum, gaze assessment (eye movements), vestibular tests, imaging, subjective assessment (questionnaires)

Question 3

4 vestibular tests in vestibular diagnosis

Answer 3

caloric test, vHIT, VEMP, rotational test

Question 4

2 imaging techniques in vestibular diagnosis

Answer 4

CT scan, MRI

Question 5

symptoms of vestibular lesion

Answer 5

vertigo, dizziness and giddiness, unsteadiness, self-motion perception

Question 6

define vertigo

Answer 6

illusion of movement (usually rotational or ‘true vertigo’, whereas dizziness and giddiness are more vague)

Question 7

define unsteady

Answer 7

off balance (bilateral vestibulopathy)

Question 8

2 locations of peripheral vestibular disorders

Answer 8

labyrinth, vestibulocochlear nerve

Question 9

4 examples of peripheral vestibular disorders

Answer 9

vestibular neuritis, BPPV, Meniere’s disease BVF, UVF

Question 10

location of central vestibular disorders

Answer 10

CNS (brainstem/cerebellum)

Question 11

3 examples of central vestibular disorders

Answer 11

stroke, MS, tumours

Question 12

evolution of vestibular disorders

Answer 12

acute -> intermittent -> recurrent -> progressive

Question 13

2 examples of acute vestibular disorders

Answer 13

vestibular neuritis (‘labyrinthitis’), stroke

Question 14

example of intermittent vestibular disorder

Answer 14

benign paroxysmal positional vertigo (BPPV)

Question 15

2 examples of recurrent vestibular disorders

Answer 15

Meniere’s disease (rare), migraine (common)

Question 16

example of progressive vestibular disorder

Answer 16

acoustic neuroma on vestibulocochlear nerve, causing degeneration

Question 17

7 differential diagnoses to vestibular disorders which present with similar dizzy symptoms

Answer 17

heart disorders, presyncopal episodes, orthostatic hypotension, anaemia, hypoglycaemia, psychological, gait disorders

Question 18

parts of vestibular system (pyramidal)

Answer 18

spinal cord -> ponto-medullary junction (where nerve to peripheral vestibular organ) -> vestibular cerebellum -> thalamus -> cerebral cortex

Question 19

what is vestibular-motion perception

Answer 19

sensation of motion (self or environment)

Question 20

what is oscillopsia

Answer 20

defect in seeing environmental motion (indicates nystagmus)

Question 21

define nystagmus

Answer 21

seeing visual world move (slow phase, fast phase repeated)

Question 22

dizziness or vertigo

Answer 22

describe symptoms in words: self or environmental motion (eyes shut), seeing room move; origin may come from ear or brain

Question 23

illusory self-motion: low current

Answer 23

feeling of gentle rocking of self

Question 24

illusory self-motion: high current

Answer 24

feeling of violent spinning of self and room

Question 25

most common emergency room vertigo diagnoses, which history and examination are aimed at

Answer 25

benign paroxysmal positional vertigo (BPPV) - always look for, vestibular neuritis (bipalsy), migrainous vertigo, stroke, mixed (Meniere's <1% - disorder of inner ear)

Question 26

3 simple measurements to take when acute vertigo suspected

Answer 26

postural blood pressure, arterial saturation, ECG

Question 27

what 3 things are ruled out when diagnosing acute vertigo

Answer 27

presyncope, pulmonary embolism, cardiac dysrhythmia

Question 28

3 core examination areas for acute vertigo

Answer 28

eyes, ears, legs

Question 29

4 investigations of core eye examination for acute vertigo

Answer 29

gaze, vestibulo-ocular reflex, hallpike, fundoscopy

Question 30

investigation of core ear examination for acute vertigo

Answer 30

otoscopy

Question 31

investigation of core legs examination for acute vertigo

Answer 31

gait (and tandem)

Question 32

gaze in patients with peripheral nystagmus

Answer 32

nystagmus suppressed with vision, so without visual fixation, nystagmus increases intensity so is peripheral (affecting ear)

Question 33

vestibulo-ochlear reflex in patients with nystagmus

Answer 33

doll's eyes and head impulse test - tell which way nystagmus is as eyes taken off target when head moved - can tell peripheral

Question 34

fundoscopy in patients with acute vertigo

Answer 34

retina, spontaneous nystagmus, effect of visual fixation on nystagmus

Question 35

otoscopy in patients with acute vertigo, and impact on antibiotic admission

Answer 35

rarely informative except for unilateral peripheral vestibular loss (e.g. Herpes) or suppurative infection in meningitis, so oral antibiotics never indicated

Question 36

gait and tandem walking in patients with acute vertigo

Answer 36

narrow gait?, count how many mistakes out of 10 tandem steps, see if eye closure affects balance, and can maintain balance for >20s without vision

Question 37

investigating BPPV (benign paroxysmal positional vertigo): position and duration

Answer 37

lying back in bed, with very brief duration (seconds as beware prolonged malaise)

Question 38

investigating BPPV (benign paroxysmal positional vertigo): red flags

Answer 38

headache, atypical nystagmus

Question 39

investigating BPPV (benign paroxysmal positional vertigo): typical vs atypical vs complex

Answer 39

typical: latency of 10 seconds before see nystagmus when tilt head back due to crystal movement (localise canal), atypical and complex: down-beating nystagmus is central); adaptability, fatiguability

Question 40

treating posterior canal BPPV (benign paroxysmal positional vertigo)

Answer 40

epley, semont (right hallpike and semont) to remove crystal debris from semicircular canal

Question 41

define vestibular agnosia in acute traumatic brain injury

Answer 41

lack of sensation of dizziness despite a peripheral vestibular activation (evoked nystagmus) indicates a loss of vestibular sensation; nystagmus but don't see world spin

Question 42

vestibular neuritis: onset

Answer 42

subacute (minutes -> hours) continuous vertigo

Question 43

vestibular neuritis: symptoms

Answer 43

obvious "vestibular" nystagmus, positive head impulse test, normal gait

Question 44

vestibular neuritis: treatment

Answer 44

vestibular sedatives (24-36 hours), mobilise at day 3, treat any BPPV or migraine

Question 45

vestibular neuritis: 5 red flags

Answer 45

headache, gait ataxia, hyperacute onset, vertigo and hearing loss, polonged symptoms (>4 days)

Question 46

vestibular neuritis red flags: cause of 40% headaches

Answer 46

posterior circulation stroke

Question 47

vestibular neuritis red flags: cause of gait ataxia

Answer 47

may be only non-vertiginous manifestation of cerebellar stroke

Question 48

vestibular neuritis red flags: what does hyperacute onset suggest is origin

Answer 48

vascular

Question 49

vestibular neuritis red flags: what does vertigo and hearing loss indicate

Answer 49

AICA or ugent ENT problem

Question 50

vestibular neuritis red flags: what do prolonged symptoms indicate

Answer 50

floor of 4th ventricle problem

Question 51

acute vestibular migraine: history, symptoms and diagnosis

Answer 51

history of migraine, acute vertigo with/out headache and recurrent episodes, diagnosis of exclusion

Question 52

acute vestibular migraine: main differential diagnosis

Answer 52

cerebellar stroke

Question 53

acute vestibular migraine: 5 red flags (same for cerebellar stroke)

Answer 53

headache, gait problems, hyperacute onset, hearing loss, prolonged symptoms (>4 days)

Question 54

cerebellar stroke: symptoms

Answer 54

thunderclap onset vertigo, difficulty walking, headache