Vestibular rehab Flashcards
- What is Nystagmus
- What are the components of the vestibular system?
- related to disruption of vestibulo-ocular reflex (VOR)
- peripheral components: semicircular canals, utricle, saccule, vestibular ganglion
- central components: vestibular nuclei, cerebellum, medial longitudinal fasaciculus (MLF), medulla
Utricle vs saccule
- utrical: horizontal movement
- saccule: verticle movement
Functional pairs of the SCCs
Excitation of R. horizontal SCC
- inhibition of L. horizontal
- excite R. medial rectus, L. Lateral rectus
- inhibit L. Medial rectus, R. lateral rectus
Funcional pairs of the SCCs
Stimulate right posterior SCC
- inhibit Left anterior SCC
- excite R. superior oblique, L. Inferior rectus
- inhibit R. inferior oblique, L. superior rectus
What are the functional pairs fo the SCC
- horiziontal canals
- right anterior and left posterior
- left anterior and right posterior
What are some common causes of peripheral vestibular dysfunction
- acoustic neuroma
- labyrinthitis/neuronitis
- age-related hair cell degeneration
- drug-induced hair cell toxicity
- trauma - concussion
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Peripheral Nystagmus
- towards more active side
- nystagmus to contalateral side
- slow movement towards side of lesion
- fast phase away from lesion
- can be decreased with gaze fixation
- nystagmus is mostly horizontal a little torsional
- gaze dependent: amplitude and velcity depend on eye position
Gaze dependent nystagmus
- changes as peripheral dysfunction improves
- 3rd degree/first day
- 2nd degree
- first degree
First day gaze dependent nsytagmus
- 3rd degree nystagmus
- no matter where you look you get nystagmus
- nystagmus when looking straight, toward or away from lesion
- worst when looking away from lesion (nothing inhibiting on side/impaired)
2nd degree gaze dependent nsytagmus
- nystagmus with gaze center or away from lesion
1st degree gaze dependent nsytagmus
- nystagmus with gazing away from lesion
Medial longitudinal fasciculus
- a bundle of nerve fibers in the brainstem that coordinates eye movements and integrates them with head and body movements
Central Vestibular Dysfunction causes
- vascular insufficiency/infarct
- tumor
- trauma
Central nystagmus
spontaneous
- does not change with gaze fixation
- tends to be one plane: horizontal (vertical or torsional)
- with gaze to one side: no change or reverses direction
Types of Central nystagmus
- different types, depending on area of CNS involved
- torsional: dorsolateral medulla
- downbeat: cerebellum
- upbeat: dorsal upper medulla
- others: seesaw, periodic alternating, latent
Nystagmus in BPPV
- related to push-pull mechanism of VOR/functional pairs of SCCs
- testing position induces nystagmus
- affected side = hyperfunction
Right posterior 1. cupulolithiasis vs 2. canalithiasis
- Persistent UBN + right torsion
- Transient UBN + right torsion
Left posterior 1. cupulolithiasis vs 2. canalithiasis
- persistent UBN + left torsion
- Transient UBN + left torsion
right anterior 1. cupulolithiasis vs 2. canalithiasis
- persistent DBN + right torsion
- transient DBN + right torsion
left anterior 1. cupulolithiasis vs 2. canalithiasis
- persistent DBN + left torsion
- transient DBN + left torsion
Horizontal 1. cupulolithiasis vs 2. canalithiasis
- Persistent ageotrophic
- Transient geotropic
Common iin Central vs peripheral dysfunction:
- ataxia
- smooth pursuit movements
- hearing loss, tinnitus
- vertgio
- ataxia: peripheral
- smooth pursuit movements: central
- hearing loss, tinnitus: central or peripheral
- vertgio: more pronouced usually in peripheral
What are some tests of vestibular function
- head thrust: central
- dynamic visual acuity: central
- head-shaking nystagmus
- clinical test for sensory integration of balance
- balance - romber, berg SLS
- gait: dynamic gait (central and peripheral)
- four square step test
- balaanace error scoring system
- fukuda stepping test
- bestest
- sensory organization test
