6.1 - Vestibular Flashcards
Describe the anatomy of the vestibular system / inner ear
“Labyrinth” = inner ear
Components:
- Semicircular canals
- Vestibule / Otolith organs = utricle & saccule
- Cochlea
Is the “inner ear” part of the peripheral or central NS
Peripheral
Cranial nerves = peripheral NS
Describe the functions of the SC canals & otolith organs
Semicircular canals - detect angular acceleration (rotational movements)
Otolith organs - detect linear acceleration
Saccule - vertical movements
Utricle - horizontal movements
Define nystagmus
How is it named?
Repetitive uncontrolled movements of the eye
Named based on the “fast phase”
Define vertigo
Sensation of spinning, feeling off-balance, etc.
Define saccade
Rapid eye movment
“Corrective bounce”
Describe the clinical presentation of vestibular disorders
Dizziness, vertigo
“Spinning”
Instability, ataxia, falls
Nystagmus
What are common vestibular disorders to be aware of?
BPPV
Meniere’s disease
Acoustic neuroma
Neuritis
Meniere’s Disease
What is it?
Clinical Presentation
Treatment
A vestibular disorder caused by overaccumulation of endolymph (fluid in the labyrinth / inner ear)
Clinical Presentation:
- Vertigo that lasts for HOURS to DAYS
- “fullness of ear”
- Tinnitus
Treatment:
- PT –> refer back to provider
- Fluid control, diuretics
BPPV
What is it?
Clinical Presentation
Special test
Treatment
Benign Paroxysmal Positional Vertigo
- Otoconia (“crystals”) break loose from utricle and enter into the semicircular canal
- During head movements, otoconia –> excessive movement of the endolymph / cupula
Clinical Presentation:
- Vertigo - 30 sec –> few minutes
- Vertigo occurs in response to head movements / position changes
Posterior Canal:
- UPBEATING & TORSIONAL NYSTAGMUS
- Torsional towards the involved side
Horizontal Canal:
- Horizontal nystagmus (twds the involved side)
Special Tests:
- Dix-Hallpike - posterior canal
- Roll Test - Horizontal canal
Treatment:
- Epley’s Maneuver - posterior canal canalolithiasis
- Semont Liberatory Maneuver - posterior canal cupulolithiasis
- BBQ Roll - Horizontal canal
Describe how to perform the dix-hallpike maneuver
Down ear = involved ear
Testing L ear:
- L head turn 45 deg
- Cervical ext 45 deg
Describe how to perform the roll test
L turn = testing L ear (“down ear”)
- Supine
- HEAD ELEVATED to 20 deg (get on plane w/ horizontal canals)
- Roll head to each side
Describe how to perform the head impulse test
What does a positive test indicate?
(+) test = corrective saccade (unable to maintain gain fixation)
(-) test = able to maintain gaze fixation
Deficient VOR on the SAME side as head turn
- L head turn = L involved ear
(+) test indicates a vestibular pathology (specifically of the horizontal semicircular canal)
Describe how to perform the vertebral artery screen
Extension, sidebend, and rotation to same side
Tests CONTRALATERAL vertebral artery
- “Stretching” the artery
Describe canalithiasis vs cupulolithiasis
Canalithiasis
- Otoconia are free floating in the endolymph of the SCC
- Delayed onset of sx
- Vertigo presents for shorter duration (~1 min)
Cupulolithiasis:
- Otoconia are adhered to the cupula
- Immediate onset of sx
- Sx are persistent & longer duration (>1 min)
