Vestibular Exam and Treatment

Question 1

3 TYPES OF VOR TESTS

Answer 1

-dynamic visual acuity

-head impulse test

-clinical screen for gaze stability: head turns with gaze on a fixed target

Question 2

Dynamic visual acuity test:

Answer 2

-a test of VOR

compare what the patient can read on the Snellen chart with and without head movement
-240 bpm recommended
-how many lines change with head movement?–> record

POSITIVE: loss of >2 lines of visual acuity (blurred vision) –> vestibular dysfunction suggested, catch up saccade

Question 3

Head impulse test characteristics:

Answer 3

-assess all canals
-ask pt to stare at the examiner’s nose
-make it unpredictable

CHIN TUCK
-30 degrees to test horizontal plane

POSITIVE: eyes “slip” off the target and require a catch-up saccade to re-focus on the target

Question 4

Clinical Screen for Gaze Stability: head turns with gaze on fixed target (VOR screen)

Answer 4

-go to both sides, left center then right center
-hold their thumb at eye level –> standardized to the patient

• Not a validated test but has intra-patient reliability
• Can be used for treatment
• POSITIVE: blurred vision during head motion or patient reports or demonstrates more difficulty on one side to maintain gaze fixation on target

Question 5

3 TESTS FOR POSTURAL CONTROL (balance or orientation)

Answer 5

1. mCTSIB-> balance analysis of sensory weighting
2. Tandem stance-> head righting
3. Functional Gait Assessment (FGA)
   -cut off score: <23/30 - fall risk

Question 6

Education intervention for vestibular hypofunction:

Answer 6

1. 3 balance systems
2. Rehab course: retrain the appropriate weighting of sensory input from each system,
   Prolonged compensation can lead to more dizziness (PPPD)
3. Restore normal movement patterns, and discourage avoidance behaviors
   –> walk fluidity, gaze forward, not down, normal cadence
   –> try not to touch surfaces

Question 6

3 movement perception tests:

Answer 6

1. Visual
   -VOR cancellation
   –Positive: dizzy with eye movement, not head (vestibular) or body movement provoked
2. Somatosensory:
   -Motion sensitivity quotient- quantify dizziness with 16 head or body positions

-DHI- Dizziness Handicap Inventory- 25-question self-assessment 0-100
— Mild 0-30, Moderate 31-60, Severe >60

3. Vestibular
   - Sensation of Motion at Rest: Vestibular and Somatosensory Systems Matching
   —Test: Seated without back support, instruct patient to close eyes and ask if they feel any motion inside of their head
   —Positive: They feel a sensation of motion in their head

Question 6

mCTSIB characteristics:

Answer 6

EO, firm - viusal, som, vestibular
EC, firm - som, vestibular
EO, foam - visual, vestibular
EC, foam - vestibular only (if weak, may have reliance on somatosensory or impaired vestibular referencing)

-if the patient has a challenge going from a wide BOS to a narrow BOS–> somatosensory deficit

Question 7

What is the goal speed for re-training (adaptation) of the VOR?

Answer 7

1 Hz or 120 bpm

Question 8

How can you train postural control and balance (adaptation)?

Answer 8

-ankle strategy: somatosensory - tilt board
-hip strategy: vestibular-tandem stance, toe taps, seated reaching
-EC standing on foam- forced use vestibular system

-tandem stance for vestibular system: head righting, seated, on ball

FGA- look at challenging components and perform those

Question 9

Interventions for movement perception (adaptation and habituation)

Answer 9

-decrease visual load to dec symptoms–> take breaks and pacing
-VORc training
-Exposure in small doses to grocery store/mall –> habituation to busy environments
-try settling the vestibular system with 1-5 minutes of weights on the shoulders

Question 10

Dosing principles for vestibular hypofunction intervention:

Answer 10

• Low and slow
• Visual and Somatosensory Hypervigilance will manifest when a threat
  is perceived such as loss of balance or onset of dizziness
• Should recover within an hour from most exercises
• Reiterate high repetitions are needed for neuroplastic changes but
  must be the right type of performance, practicing the wrong things
  have already made them experts at the wrong things
• Time is not a factor of when they will improve, correct practice is the
  determining factor, which takes time

Question 10

Hallmarks of PPPD in the case - Amanda

Answer 10

• PPPD- triggering event was a history of BPPV, recent stress of family needs increasing and changing of jobs contributed to visual demand
• Highly symptomatic, long history of symptoms suggests well-engrained
  balance patterns especially reliance on vision, can expect a long recovery
• Notes depression- may benefit from medical management (SSRI)

-worse with head or visual movement
-best in the am, symptoms worsen as the day goes on

FINDINGS:
-negative HIT, DVA
-sensation of motion at rest
-perception that balance is very poor despite performance