Vestibular Disorders Flashcards
What systems may be at fault when their is dizziness
cardiovascular, neurological, visual, psychogenic, cervicogenic, meds, vestibular
What are 3 vestibular functions
Gaze stabilization
Postural stabilization
Resolution of sensory motor mismatch
What does gaze stabilization do
Keeps objects in visual field clear with head movement
What does postural stabilization do
Maintain balance and equilibrium
What is the result of sensory motor mismatch
Sea sickness
Motion intolerance
How many semicircular canals are there? Names?
Function
3 Horizontal, anterior, posterior
gaze/angular displacement of the head
How do the semicircular canals detect angular displacement of theh ead
Movement of endolymph within the canals will deflect hair cells and excite or inhibit neurons (CNVIII)
How many otoliths are there? names?
2
Utricle
Saccule
Function of utricle
Detects horizontal plane motion
Function of saccule
Detect sagittal plane motion
Combined function of utricle and saccule
Detect acceleration and deceleration, gravitational pull = Postural
What are 3 common vestibular S&S
- Vertigo
- Dizziness
- Oscillopsia
What is vertigo?
the subjective experience of nystagmus (room spinning around you) - get it with BPPV * always vestibular in origin
What is dizziness
discrepancy between R and L side, patient can’t work out where they are in space
- *non-specific, may or may not be vestibular in origin
Is vertigo or dizziness always vestibular in origin
Vertigo
What is oscillopsia
Blurred vision (Not diplopia)
Which antibiotic effects the vestibular system
Gentomycin
What does BPPV stand for
Benign paroxysmal positonal vertigo
Of people with BPV, 90% present with crystals in the _____, 80% of these are ____
in Posterior SCC
80% canalithiasis (free floating in canal)
BPPV S&S
brief (< 30 sec), delayed, transient vertigo with looking up/down, rolling to that side of bed, sit to supine;
+/- vertigo,
nystagmus,
vomiting
BPPV AX
Dix Hallpike * look for down beating nystagmus
Contraindications to Dix Hallpike
cervical spine instability, VBI, Arnold- Chiari malformation, acute whiplash, RA, prolapsed IV disc with radiculopathy, cervical myelopathy
BPPV Rx
Modified Epley Maneuver*, Semont/Liberty maneuver, Brandt-Daroff - very good prognosis after first treatment
What is improtant o do after Maneuvers to treat BPPV
keep head down at end of maneuver because you can put the crystal in the horizontal canal
What is Meniers Disease
Over accumulation of endolymph
What is the vestibulo occular reflex (VOR)
- reflex that moves your eyes in the opposite direction that your head is turning
- allows for visual fixation*
Is VOR deficient in UVL (unilateral vestibular loss) or BVL (Bilateral vestibular loss)
Both
Causes of UVL
Infection, trauma, disease (Meniere’s Disease), surgery
Acute S&S of UVL
- spontaneous nystagmus away from the affected ear
- reduced VOR
- vertigo (resolves in a few days)
- dizziness
- oscillopsia
- imbalance
- ?vomiting
Chronic S&S of UVL
- dizziness, oscillopsia, imbalance
- symptoms worse after rapid head movements: depends on compensation
UVL Ax
- head-thrust, dynamic visual acuity test, balance and gait assessment + Dix Hallpike
UVL Rx
- exercises to resolve conflict and symptoms (adaptation exercises, balance, walking program, functional tasks)
- education on impact of stress on symptoms
- maintain general fitness
- address falls risk, mobility aids
- improve any balance deficits * 6-8 wks
Is BVL always equal side to side
No can be unequal
Is the dizziness and vertigo in BVL
No
What normally causes BVL
Ototoxic drugs (gentamicin)
BVL S&S
Decreased balance with eyes closed + Increase oscillopsia
What are some general ototoxic meds
antibiotics (gentamicin) anticancer drugs env. chemicals loops diuretics aspirin
Balance Ax
- static (Romberg
- sharped Romberg (tandem stance))
- dynamic (reach arm forward
- movement with eyes opened and closed)
- composite tests (berg)
Different Gait Ax
eyes open/closed
head turns
different surfaces
negotiating objects
Central vestibular disorders Causes
- stroke
- TBI, MS
- tumor
- neurodegeneration
- epilepsy
Central vestibular disorder red flags:
direction changing nystagmus
inconsistency in test results
Central vestibular disorders Dx
By a collection of occulomotor tests
Central vestibular disorders Rx
Based on neuroplasticity
- Exercises (habituation, substitution, balance, walking program, functional tasks
8-12 weeks
2 types of motion sensitivity
1) sensitivity to head movement
2) sensitivity of moving environment
Motions sensitivity Rx
8–12 weeks of sensorimotor mismatch exercises
Cervicogenic dizziness Dx
Disorder of exclusion
Cervicogenic dizziness Rx
management of vestibular dysfunction
- proprioception neck symptoms
- Increase motor control and endurance (deep neck flexors)
What is an acoustic neuroma?
When is it most common?
What does it cause?
- intracranial tumor of myelin around CN VIII
- common later in life 50-60 yrs causes central vestibular loss
