Vestibular Rehab Flashcards
Purposes of Peripheral Vestibular System
Stabilize visual images on the fovea of the retina during head movement
Maintain postural stability
Provide information used for spatial orientation
What are the SCC primarily involved in?
Gaze stabilization
What are the otolith organs?
Saccule & Utricle
What do the otolith organs respond to?
Linear acceleration and gravity, assist with postural stability
What flows freely within the SCC and why?
Endolymph. Moves the otoconia in the cupula (sensory receptors)
What is the tonic firing rate?
80 pulses per second
Whats the relationship of the tonic firing rate?
For each degree/sec change in head velocity there is a 1 pulse/sec change in firing rate.
What is VOR?
Vestibulo-ocular reflex. Maintains gaze stability during rapid head movements.
What velocity does VOR operate up to?
400 deg/sec (60-400)
What maintains gaze stability when head is moving at less than 60 deg/sec?
Smooth pursuit.
What is the push-pull mechanism?
SCC’s work in pairs. Right ant/left post, right post/left ant, right and left horizontal.
How does the push pull mechanism work?
As head is turned to the RIGHT, the R horizontal SCC is depolarized = increased firing rate, and L is hyperpolarized = decreased firing rate.
What is the inhibitory cut off?
Hyperpolarization can only go to 0 not to neg numbers.
What might people with vestibular problems have a history of?
Dizziness, vertigo, lightheaded, disequilibrium, oscillopsia
How do you measure symptoms?
VAS, Dizziness Handicap Inventory (DHI), Functional disability scale, Motion sensitivity quotient.
FReq/duration of episodes, circumstances of provocation.
How is the direction of nystagmus named?
By the FAST eye movement.
When is nystagmus suppressed?
In the light and when pt is fixated on target.
What is pendular nystagmus?
No fast or slow phase. Caused by CNS lesion. Usually cerebellum..
Contraindications to Head Thrust Test
Cervical instability, recent whiplash injury, screen c-spine.
Which ear is the fast phase of nystagmus towards? Slow?
Fast: The healthy ear
Slow: the involved ear
Vestibular testing
Head thrust Head shaking induced nystagmus Clinical Dynamic Visual Acuity test Caloric Testing Rotary Chair Testing
Otolith Tests
VEMP
Subjective Visual Vertical (SVV)
Subjective Visual Horizontal (SVH)
Signs of central problem
Rare - less intense
Upbeat or pendular nystagmus.
Lateropulsion/head tilt (SVV & ocular torsion)
Ocular tilt reaction
Peripheral pathology
Mechanical (BPPV)
Decreased receptor input
What is BPPV?
Benign paroxysmal positional vertigo
What causes BPPV
Otoconia are displaced in the SCC. Sx precipitated by change in head position (posiitonal vertigo, dizziness, nausea/nystagmus)
What is the main treatment for BPPV?
Particle-repositioning maneuvers, if those fail then habituation.
What are the particle repositioning maneuvers?
Epley, Liberatory-Semont, BBQ Roll
What is Meniere’s Disease?
Low freq hearing loss, episodic vertigo, maybe tinnitus
related to endolymph build up
gaze/postural stability
What is a perilymphatic fistula?
Rupture of oval or round window (membrane between middle/inner ear), fluids leak into middle ear = vertigo/hearing loss. PT contraindicated. Unless hypofunction.
What is an acoustic neuroma?
Vestibular schwannoma - benign tumor CN VIII
Progressive hearing loss, tinnitus, dysequilibrium
Balance/stab exercises.
What else is motion sickness called?
Mal de Debarquement
What is the sensory Conflict Theory?
Ongoing conflicting signals. Proprioceptive, vestibular, visual systems.
What are symptoms of Motion sickness?
Pallor, nausea/emesis, diaphoresis, motion sensitivity
medication/habituation.
Migrane related dizziness
similar to peripheral vestibular lesion. Vascular event occurs in vestibular structure. Migrane with/without aura, imbalance/vertigo without hearing loss or tinnitus. Throbbing headache, made worse by activity, nausea, sensitivity to light/noise.
Contraindications to Vestibular Rehab
Unstable vestibular disorders Sudden loss of hearing Increased feeling of pressure in the ears Severe ringing in one or both ears Discharge of fluid from ears/nose Caution with acute neck injuries.
Positional Tests
Hallpike-Dix
Roll Test - horizontal SCC
In the hallpike-dix which ear is the ear being tested?
The one toward the ground in end position. Anterior/posterior SCC
Canalithiasis
Free floating otoconia
Cupulotlithiasis
Adherent otoconia
Epley Maneuver
Canalith repositioning maneuver.
Hallpike dix - then rotate 45 deg –> SL -> 45 deg again –> sit up. Ant/post SCC.
BBQ Roll
Canalith repositioning maneuver. TO Affected side first. Roll test, but keep rolling into prone face into table, keep head down and sit up. Keep head minimal movement 1 day. Horizontal SCC
Liberatory Semont
Hallpike dix –> then switch person to other direction without moving head, “bang” head 3 times. Sit up. Can apply soft collar. For adherent otoconia in posterior SCC.
Habituation exercise
Brandt-Daroff
Gaze Stability exercise
VOR 1, VOR 2
Fukuda Stepping
close eyes and march 30 seconds or until safety risk. Balance/inner ear test.
