Vestibular disorders

Question 1

Sensation of inappropriate movement – Spinning

Answer 1

Vertigo

Question 2

_______ is usually “ear” generated and causes a sensation of spinning

Answer 2

Nystagmus

Question 3

main role of ear is to

Answer 3

keep eye fixed on target

Question 4

Ear is constantly sending info to brain on baseline activty… if both ears are in same state means

Answer 4

you’re not moving

Question 5

When you turn right, your right ear will send signals, the response is:

Answer 5

eyes accomidate to movement

Question 6

loss of function of left ear: you don’t get normal tonic input so more input comes from right… brain intereprets this as..

Answer 6

you turning your head right = Unilateral hypofunction

Question 7

Stimulation of a semicircular canal generates eye movements in the plane of that canal

Answer 7

Ewalds first law

Question 8

Ewalds first law

Answer 8

Stimulation of a semicircular canal generates eye movements in the plane of that canal

Question 9

Horizontal canal cauases eye movements to go

Answer 9

left and right

ampullopetal flow

Question 10

Superior canal causes eyes

Answer 10

to go obqlique and off to the side

ampullofugal flow

Question 11

Posterior canal causes eyes to

Answer 11

go oblique and to the back

ampullofugal flow

Question 12

semicircular canals are at

Answer 12

right angle

Question 13

stimulate the right horizontal canal, eyes move

Answer 13

left

Question 14

stimulate the right superior canal, eyes move

Answer 14

eyes move UP, then rotate left

Question 15

stim the right posterior canal, eyes move

Answer 15

eyes move down, then rotate left

Question 16

Nystagmus occurs

Answer 16

Opposite the direction evoked by canal excitation

Question 17

Nystagmus is a Corrective mechanism

Answer 17

– Rapidly bring eyes back to where they belong

Question 18

if right horizontal canal is more active, nystagmus causes eyes

Answer 18

to the left

Question 19

right superior canal is more active, nystagmus causes

Answer 19

eyes to go down and left

Question 20

With nystagmus the eyes drift to the

Answer 20

weak side… then jerk back to more active side

Question 21

if i stim right horizontal canal, i will see nystagmus that

Answer 21

beats to right… beats in plane of stimulated canal or towards more active side

Question 22

if someone comes in and complains of dizziness but no nystagmus…

Answer 22

CANNOT be ear related

Question 23

Three tests to uncover nystagmus

Answer 23

Head thrust
Gaze evoked nystagmus
head shake test

Question 24

Most important vestibular reflex
• Maintains eye position during motion
• Extremely fast responses
• Disturbances are demonstrated by eye examination

Answer 24

Vestibulo ocular reflex

Question 25

Loss of VOR on left side when you do a head shake:

Answer 25

eyes will pulse to the right

Question 26

Gaze in the direction of the fast phase of nystagmus increases amplitude and frequency

Answer 26

alexanders law

Question 27

Clinical situation: patient looks left and see a slow, solid nystagmus patient looks right and see it's more active diagnosis?

Answer 27

something is going on with the left eye

Question 28

3 days post op left acoustic neuroma pt no longer has visible nystagmus but i can bring out a stronger nystagmus by having:

Answer 28

having patient look right | left is still hypofunctioning

Question 29

Excitatory response for angular VOR are greater than inhibitory responses

Answer 29

Ewalds 2nd law | turing towards a side activates that side more then turning away from a side's inhibtion

Question 30

What happens to a normal patient during head shake exam?

Answer 30

nothing.. not nystagumus because summed up equally on both sides

Question 31

during a head shake exam with a patient that has left side weakness... what happens when you're done

Answer 31

see right beating nystagmus

Question 32

loss of bone covering over superior canal is

Answer 32

superior canal dehiscence

Question 33

you can mimic superior canal dehiscence by:

Answer 33

tones, exercise, pressure

Question 34

• Posterior canal canalithiasis • Posterior canal activated by movement – Otoconia move in canal simulating movement (crystals) • Nystagmus is toward affected ear and rotary in nature – Geotropic beating (toward the ground)

Answer 34

Benign Paroxysmal Positional Vertigo BPPV

Question 35

To diagnose BPPV

Answer 35

Dix-Hallpike Testing | chaning a lightbulb or getting the bed spins

Question 36

• Head thrust and head shake can uncover a

Answer 36

weakness

Question 37

Gaze can point to the

Answer 37

more active canal

Question 38

Sound can stimulate a

Answer 38

dehiscent superior canal

Question 39

Loss of vestibular function in all canals • Can elicit signs of unilateral weakness • Hearing loss • Viral or bacterial in origin – Assess history of URI or otitis media

Answer 39

Labyrinthisis

Question 40

Vestibular Neuronitis affects:

Answer 40

• Superior Vestibular Nerve – Horizontal and superior canals – Posterior canal spared (BPPV)

Question 41

During Acute Phase of vestibular neuronitis

Answer 41

– Nystagmus beating away from affected ear

Question 42

During Chronic Phase of vestibular neuronitis

Answer 42

>6monthsafterinitialattack • Weakness in balance function on one side • Sensitive to rapid head movements • Rare to have recurrence of initial attack • May develop BPPV • 30%developanxiety/”fearofdizziness”

Question 43

``` 1st week • Sudden and intense vertigo and imbalance • Need to stay still • Nausea and vomiting • Typically seen in ER ```

Answer 43

Vestibulo neuronitis

Question 44

Question: I suspect vestibular neuritis in a patient with a single long vertigo attack 1 year ago. To identify a unilateral vestibular weakness and which ear was affected, my exam should include: A. Head thrust test B. Head shake exam

Answer 44

Both A and B – Head thrust may show refixation saccades with thrust to the weak ear – Head shake should uncover asymmetry with nystagmus beating to the good ear (away from the affected ear)

Question 45

Inner ear fluid imbalance Episodic vertigo Fluctuating hearing loss

Answer 45

Menieres disease

Question 46

Meniere’s Disease | Episodic Vertigo

Answer 46

``` Recurrent and episodic • Vertigo • Last 30 minutes to ~4 hours • Minimal imbalance between attacks • Unilateral balance weakness – fast turns or head rotations ```