Vestibular Disorders

Host: Jimmy McKay, PT, DPT

Featured Guest; Alicia Flach, PT, DPT, NCS

Notes by Alexis Lancaster

Vestibular Disorders

 

What is it?

Disruption that can occur from vestibular apparatus (inner ear) through the cranial nerve to the CNS where the information is processed

Any disruption along this path will cause a vestibular disorder

 

Anatomy

Peripheral vestibular system

BPPV: problems within the vestibular apparatus, specifically semicircular canal

Creates sensation of moving, pt feels dizzy

Problem with cranial nerve 8 (before synapse in brain stem)

Problem here= peripheral problem

Central vestibular system

After cranial nerve 8 synapses in brainstem

Travels different pathways to locations within the brain

Problem here= central problem

 

Differential diagnosis

Dizziness can be due to different things

Vertigo: room spinning, could be peripheral or central vestibular problem

Feeling of imbalance or disequilibrium, pt doesnt feel steady on their feet. Could be peripheral or central vestibular problem

Unrelated to vestibular system

Polypharmacy

Orthostatic hypotension (pt complains of feeling light-headed, passing out, fainting)

Low blood sugar (hypoglycemia)

Migraines

Get to the root of how the patient describes their dizziness

 

Special Tests

Subjective interview: try to understand when it happens, how long it has been going on, how long it lasts when it happens, does it come and go or is it constant, is it related to positional changes?

Rule out/in peripheral condition, BPPV: Dix Hallpike, head thrust test, dynamic visual acuity test

Look for central signs throughout exam

Hypermetria with saccades

Abnormal changes in the ability to perform

Vestibulo-occular reflex cancellation: being able to follow a moving object with your eyes and head moving in the same direction

Rule in the vestibular system overall, rule in/out peripheral vs. central

 

Treatment

Common encounter: BPPV

Managed through canalith repositioning maneuvers (otoconia getting stuck in canal): Epley and BBQ Roll

Dysfunction of peripheral nerve/hypofunction

Gaze stabilization Tx

Movement sensitivity/central component

Habituation

Exercise

Graded exposure

 

Sample Question

A physical therapist evaluates a patient who reports dizziness when getting out of bed. The physical therapist suspects the pt is experiencing symptoms related to BPPV. Which of the following would be the most appropriate assessment to confirm the presence of BPPV

Head thrust test

Dynamic visual acuity testing

Dix Hallpike maneuver

Clock drawing test

 

Answer: C. Dix Hallpike: it is an assessment in which an individual is moved into a position and is intended to elicit a response from the presence of otoconia in the semicircular canal. Position the patient and look for the presence of nystagmus to rule in BPPV.

 

Why the others are wrong:

A: Head thrust test looks at the ability of a patient to perform VOR (vestibulo-ocular reflex)--> specifically looks for hypofunction

B: Dynamic visual acuity testing tests for peripheral hypofunction. Perform eye chart and look at visual acuity in static position and then pt will move head side to side to see visual acuity dynamically.