Bedside Screening of Vestibular Function

Question 1

What is the romberg test?

Answer 1

Test of body’s proprioception system which requires healthy function of the dorsal columns of the spinal cord and location of joints
Typically performed as part of a neuro exam to evaluate balance but can also be used to evaluate loss of motor coordination (ataxia)
Also used to measure degree of functional disequilibrium caused by central vertigo, peripheral vertigo and head trauma
Idea is to identify patients who have a problem with proprioception but can still maintain balance by compensating with vestibular function and vision

Question 2

How do you screen VSR?

Answer 2

Romberg / Tandem Romberg
Fukuda / Stepping Fukuda (Unterberger)
Gait Assessment / Tandem Walk

Question 3

How is the romberg done?

Answer 3

Patient is asked to remove shoes, stand feet together. Arms held close to body or crossed in front. First performed with eyes open and then eyes closed for 10-15 sec
Increased sway leading to a fall (LOB) is considered a positive Romberg
Positive Romberg suggests that loss of coordination is sensory in nature and due to loss of proprioception (abnormal)
If however, a patient is ataxic and Romberg is not positive it suggests that the ataxia is cerebellar
Can be made more difficult by using tandem or sharpened stance

Question 4

How do patients with acute peripheral vestibular lesions perform on the romberg?

Answer 4

Usually inclined to move towards the side of the problem
But chronic vestibular damage does not produce deficits in the standard romberg test (not as sensitive to unilateral or non-acute deficits) - due to central compensation

Question 5

How will people with proprioceptive problems perform on the romberg?

Answer 5

Unable to stand with eyes closed and feet together

Question 6

What is the purpose of the fukuda stepping test?

Answer 6

To evaluate labyrinthine function via VSR
First published by Unterberger in 1939;
Modified in 1959 by Tadashi Fukuda MD to better quantify test results
Contra-indications: Patients must be able to maintain balance during Eyes-Closed Romberg Testing

Question 7

Who is the normative data for in the fukuda test?

Answer 7

Adult (age 18-64) and Elderly Adult (65+)

Question 8

How do you do the fukuda test?

Answer 8

Patient is asked to stand with eyes closed and hands held straight out in front of them
They are then instructed to march in place for 50 steps, a floor grid may be used
Do not bias patient with auditory/other stimuli

Question 9

How do you score the fukuda test?

Answer 9

Normal patient will be able to complete the task without significant angular deviation (i.e., less than 30-45 degrees rotation)
Abnormal patient will rotate and is considered positive (abnormal) if rotation exceeds 45 degrees for 100 step test or exceeds 30 degrees for 50 step test, or if excessive sway, translation or staggering is noted during (Fukuda, 1959)
Abnormality typically toward the lesioned side

Question 10

What is the gait assessment?

Answer 10

Qualitative observations of a patient’s ambulation can provide insight to how symptoms are affecting daily activities
Mobility aids such as canes, walkers or wheelchairs should be noted

Question 11

How is the gait assessment done?

Answer 11

Patient is asked to walk away from clinician, stop and turn, then walk back toward the clinician
The clinician should be aware of widened stance, veering to one side or the other, sway and cadence
Multiple systems contribute to ability to perform this screening

Question 12

When can tandem walk be done?

Answer 12

If the patient is able to complete the gait assessment with minimal difficulty
Individual is asked to walk heel to toe away from the clinician, stop and turn, then walk heel to toe back to clinician
Instrumented assessments may also be used to complete this screening (Timed up and Go (TUG) and Tinetti Get up and Go Test)

Question 13

How do you evaluate VOR? (screening)

Answer 13

Halmalgi Head Thrust (Head Impulse)
Active / Passive Head Shake
Dynamic Visual Acuity (Passive Head Rotation w/ Snellen Chart)
Ocular Tilt Reaction / Monocular Eye Cover

Question 14

What is impaired VOR?

Answer 14

Vestibular system detects influence of gravity and velocity of head movement
Patient symptoms therefore usually triggered by changes in head/body position or movement
Symptoms:
Head and eye coordination out of sync
Visual blurring, bouncing (oscillopsia, retinal slip)
Trouble reading signs when walking
Head turns while at a stop or in a grocery store

Question 15

What is the halmalgi head thrust (impulse) test?

Answer 15

Can be used to detect SCC dysfunction in all canals
Useful for detecting peripheral vestibulopathy
Altered VOR gain and presence of re-fixation or catch-up saccades in abnormal individuals during head thrust

Question 16

What are the types of re-fixation saccades?

Answer 16

Covert (saccades that occur during the head movement; difficult to impossible to see with the naked eye)
Overt (saccades that occur after the head movement; can be seen with the naked eye)

Question 17

How is the halmalgi head thrust performed?

Answer 17

Clinician grasps patient by the head and uses rapid unexpected head turns to examine the individual’s functional VOR
Patient is asked to keep his/her eyes focused on a target (e.g., clinician’s nose or forehead)
Head should be thrust in the direction of or plane of semicircular canals
Head movement should not exceed 20-30 degrees in any direction but must be high acceleration (>3000 deg/sec/sec)
Head should be held briefly at the end of impulse to monitor for re-fixation saccades

Question 18

What is a normal halmalgi head thrust result?

Answer 18

Will exhibit no corrective / re-fixation saccades

Question 19

What is an abnormal halmalgi head thrust result?

Answer 19

Will exhibit re-fixation saccades in direction of lesion

Question 20

What is the headshake test?

Answer 20

Evaluates the status of the patient’s velocity storage integrator
The patient is fitted with frenzel lenses or VNG goggles with eyes covered
The patient “actively” shakes their head or has their head “passively” moved back and forth horizontally at a rate of at least 2Hz for 20 seconds
After 20 seconds, the head is abruptly stopped and patient is asked to open eyes
Clinician notes if any nystagmus is observed post headshake or if any pre-existing nystagmus is enhances after-headshake

Question 21

What is the normal result of the headshake?

Answer 21

No post-headshake nystagmus

Question 22

What is an abnormal result for headshake?

Answer 22

Post-headshake nystagmus or enhances post-headshake nystagmus
If there is a post-headshake nystagmus this is a strong indicator the vestibular system is not dynamically compensated

Question 23

What are the possible outcomes of the headshake test?

Answer 23

No headshake pre- and post- headshake means no vestibular abnormality
No pre-headshake nystagmus but post shake nystagmus means it is vestibular (beats away from affected side) – asymmetry with central compensation
Pre-headshake nystagmus and increase of nystagmus post headshake means there is an asymmetry (recent injury)
Pre-headshake nystagmus and no change post headshake means that it is a central deficit

Question 24

What is the dynamic visual acuity test?

Answer 24

This test screens for oscillopsia a complaint often caused by vestibular loss especially bilateral losses
The patient is seated the proper distance from a Snellen Eye Chart and instructed to read the lowest line possible
The clinician then stands behind the patient and moves their head back and forth in a horizontal fashion (actively) or alternatively the patient can move their head themselves passively (less preferred) in a 20-30 deg arc at 2Hz
The patient is again asked to read the lowest line possible while the head is rotated
Limitation: don’t know what side is affected

Question 25

What is a normal result for the dynamic visual acuity test?

Answer 25

Patient’s will have no line change or just a single line change in visual acuity

Question 26

What is an abnormal result for the dynamic visual acuity test?

Answer 26

Those with oscillopsia will have a line change of 2 or greater during head movement

Question 27

What is the ocular tilt reaction/monocular eye cover test?

Answer 27

Misalignment of the eyes has been observed in patients with brainstem lesions or acute utricular malfunction - they will get an ocular tilt reaction due to this
This phenomena can be observed when individual is asked to stare straight ahead while a single eye is covered and uncovered
The abnormal patient will show transient shifting of eye vertically when uncovered (they will drift apart and then snap back to the same plane when it is uncovered)
This should be repeated for both eyes