Vestibular

Question 1

what stimulates the vestibular system

Answer 1

linear/angular acceleration of head

Question 2

what does vestibular stimulation cause to happen

Answer 2

clear vision with head movement
facilitate postural reflexes
orient body/head to vertical

Question 3

types of input in the vestibular system

Answer 3

visual
vestibular
proprioceptive

Question 4

what are the two areas that the sensory input in the vestibular system go to

Answer 4

vestibular nuclear complex
cerebellum

Question 5

what makes up the peripheral vestibular system

Answer 5

inner ear
CN8 until brainstem

Question 6

central vestibular system

Answer 6

nuclei and tracts in brain cortex
cerebellum
brainstem

Question 7

what is not a part of the peripheral vestibular system

Answer 7

cochlea

Question 8

what detects angular motion

Answer 8

semicircular canals

Question 9

what are the names of the semicircular canals

Answer 9

anterior
posterior
horizontal

Question 10

what is the ampula

Answer 10

enlargement at the end of each SCC

Question 11

what are the otolith organs? what is another name for them

Answer 11

utricle and saccule

aka vestibule

Question 12

what do the otolith organs detect

Answer 12

linear acceleration
static tilt of head

Question 13

how are the canals oriented

Answer 13

orthogonal
- in the plane as the opposite canal on the other side

Question 14

how are conjugate canals aligned

Answer 14

in optimal pulling directions of extraocular muscles

Question 15

what is within the bony labyrinth

Answer 15

membranous labyrinth filled with endolymphatic fluid
hair cells

Question 16

where are hair cells

Answer 16

cupula of the ampullae, utricle, saccule

Question 17

how does endolymph fluid flow? what does this do?

Answer 17

opposite the direction of canal movement
deflects the ampulla’s cupula

Question 18

where does vestibular nuclei relay info to

Answer 18

cerebellum
cerebral cortex
spinal cord
oculomotor muscles

Question 19

what is abnormal vor sign on the head impulse test

Answer 19

eyes do not stay on target and need a saccade back to the target

Question 20

describe nystagmus naming

Answer 20

fast phase

with specific direction, intensity and shape

Question 21

what does the direction of nystagmus indicate

Answer 21

which inner ear and which structure is dysfunctioning

Question 22

what nystagmus suggests a central origin

Answer 22

pure vertical
pure torsional
direction changing

Question 23

how can nystagmus be changed

Answer 23

lighting in a room
- light = suppression of nystagmus because eyes can fixate on a target
- dark = eyes cannot fixate on a target

Question 24

what mostly causes dizziness

Answer 24

peripheral causes

Question 25

what causes vestibular system dysfunction

Answer 25

abnormal firing rate between L and R peripheral vestibular apparatus impaired processing within CNS damage to CNS

Question 26

symptoms of vestibular system dysfunction

Answer 26

sensation of motion (vertigo) oscillopsia dysequilibrium motion sensitivity

Question 27

what are two things that indicate a central lesion other than nystagmus

Answer 27

lack of oscillopsia severe headache

Question 28

what are the peripheral causes of vestibular dysfunction

Answer 28

BPPV vestibular neuritis/neuroma meniere's disease ototoxicity

Question 29

what are the central causes of vestibular dysfunction

Answer 29

stroke MS neoplasms

Question 30

what medical diagnoses result in vestibular hypofunction

Answer 30

vestibular neuritis acoustic neuroma meniere's ototoxicity

Question 31

what is BPPV

Answer 31

episodic, intense vertigo related to a change in head position

Question 32

what causes BPPV

Answer 32

otoconia becoming loose, clumping together and moving into SCC

Question 33

which canal does otoconia most typically move into

Answer 33

posterior

Question 34

what are symptoms of BPPV

Answer 34

brief episodes of vertigo (<60s) precipitated by head movement

Question 35

will nystagmus be seen with BPPV

Answer 35

yes

Question 36

what is the main cause of vestibular neuritis

Answer 36

upper respiratory infection gastritis

Question 37

symptoms of vestibular neuritis

Answer 37

sudden onset 1-2 days, residual symptoms with head motion vertigo nausea vomiting intense dysequilibrium oscillopsia

Question 38

sings of vestibular neuritis

Answer 38

nystagmus abnormal VOR gain -- unilateral vestibular hypofunction

Question 39

what medical treatments are there for vestibular neuritis

Answer 39

anti-emetics, histamines, cholinergics steroids

Question 40

prognosis of vestibular neuritis

Answer 40

6 weeks to 3 months

Question 41

what is acoustic neuroma

Answer 41

benign tumor within schwann cells of vestibular nerve sheath

Question 42

s/s of acoustic neuroma

Answer 42

hearing loss dizziness imbalance -- gradual onset / worsen as tumor grows

Question 43

medical management of acoustic neuroma

Answer 43

surgery

Question 44

what is meniere's disease

Answer 44

malabsorption of endolymph fluid -- increased fluid volume

Question 45

s/s of meniere's

Answer 45

fullness feeling tinnitus fluctuating vertigo hearing loss imbalance episodic - minutes to hours

Question 46

medical treatment of meniere's

Answer 46

diuretics diet-sodium restriction shunt or ablation of vestibular nerve

Question 47

where is the damage from ototoxicity

Answer 47

bilaterally

Question 48

s/s of ototoxicity

Answer 48

impaired VOR oscillopsia dizziness imbalance

Question 49

signs of central disorder

Answer 49

dysarthria nystagmus disequillibrium

Question 50

what can be used to test vestibular system

Answer 50

video nystagmography electronystagmography

Question 51

what is computerized dynamic posturography

Answer 51

assessment of ability to maintain upright posture during various environmental conditions evaluation of somatosensory and visual influences on posture/equilibrium

Question 52

does computerized dynamic posturography diagnose peripheral vs central causes

Answer 52

no assesses one's ability to integrate various sensory inputs to maintain postural control