9.21 Vestibular Review

Question 1

Inhibited side resting rate reaches 0 at

Answer 1

180˚/s

Question 2

What happens to the inhibited side when it reaches over 180˚/s?

Answer 2

unable to contribute information

Question 3

potential causes for dizziness

Answer 3

• cardiovascular
• meds
• stroke
• epilepsy
• BPPV

Question 4

Function of vestibular system

Answer 4

• balance
• equilibrium
• gaze stabilization

Question 5

What is gaze stabilization?

Answer 5

ability to focus on an object while you’re moving your head

Question 6

What are the sensory organs in the vestibular system?

Answer 6

hair cells

Question 7

otoconia are composed of

Answer 7

calcium carbonate

Question 8

Which organs (general) have otoconia?

Answer 8

gravity sensitive organs

Question 9

The vestibular nerve uses this cranial nerve

Answer 9

CN VIII

Question 10

What is the reflex we talked about?

Answer 10

VOR

Question 11

If a pt has a peripheral vestibular problem, what are some of the vestibular symptoms that might be seen?

Answer 11

• dizziness
• nystagmus
• nausea
• imbalance
• difficulty with postural control
• unsteady

Question 12

What is oscillopsia?

Answer 12

• objects in the visual field appear to oscillate

- perception that your environment/surroundings are moving when your head moves

Question 13

medical causes of vestibular damage

Answer 13

• viral infection

- ototoxia (i.e. metal poison)

Question 14

What are symptoms of CNS vestibular problems?

Answer 14

• disconjugate movements
• purely vertical nystagmus
• dysarthria
• numbness/tingling
• facial drooping

Question 15

What is retinal slip?

Answer 15

• error signal

- blurred vision with head movement

Question 16

Associated symptoms that go along with peripheral neuritis?

Answer 16

• oscillopsia
• hearing
• dizziness

Question 17

Many pts with frequent inner ear infections will ℅ ________

Answer 17

aural fullness

Question 18

CNS/VOR following injury

Answer 18

The CNS is able to modify the VOR after an injury

Question 19

nystagmus slow phase represents:

Answer 19

vestibular input/stimulation

Question 20

fast phase

Answer 20

correction of eye in orbit

Question 21

Direction of nystagmus (from the peripheral system) is always:

Answer 21

• in the same direction

- regardless of where we gaze or position the eyeball

Question 22

What happens if the pt gazes in the direction of the fast phase?

Answer 22

nystagmus increases

Question 23

vertical nystagmus?

Answer 23

Peripheral nystagmus is not vertical

Question 24

Is nystagmus different for each eye?

Answer 24

no, same in both eyes

Question 25

Pts with this will avoid rapid movements to the affected side

Answer 25

unilateral vestibular loss

Question 26

For pts with unilateral vestibular loss, can the other side give input? What is a limiting factor?

Answer 26

• yes
• only gives input up to a speed of 180˚/sec
• after that, they receive no more input from the unaffected side

Question 27

What is needed to recalibrate the VOR?

Answer 27

• vision

- head movement

Question 28

VOR recalibration: environment

Answer 28

• need different positions, light, etc.

- context dependent

Question 29

What types of movements are beneficial for unilateral vestibular injury to help recalibrate the VOR?

Answer 29

small movements that begin to blur