Vestibular Neuronitis, Vestibular Neuronitis, Bilateral, Vestibular Schwannoma
Conditions
Keywords
vestibular rehabilitation, vestibular hypofunction
Brief summary
The purpose of this study is to determine whether exercises relieve the symptoms of dizziness and imbalance in people with vestibular deficits and improves the ability to see clearly during head movements. We hypothesize that the performance of specific adaptation and substitution exercises will result in an improvement in visual acuity during head movements while those patients performing placebo exercises will show no improvement.
Detailed description
Decrements in visual acuity during head movement in patients with vestibular hypofunction are potentially serious problems. This deficit could contribute to decreased activity level, avoidance of driving with resultant diminished independence and, ultimately, limited social interactions and increased isolation. Oscillopsia occurs because of inadequate vestibulo-ocular reflex (VOR) gain and suggests that compensation for the vestibular loss has not occurred. The purpose of this study was to examine the effect of an exercise intervention on visual acuity during head movement in patients with unilateral and bilateral vestibular hypofunction. We hypothesized that 1) patients performing vestibular exercises would have improved visual acuity during head movement compared to patients performing placebo exercises; 2) there would be no correlation between dynamic visual acuity (DVA) and the patients' subjective complaints of oscillopsia; and 3) improvement in DVA would be reflected by changes in residual vestibular function as indicated by an increase in VOR gain. Patients are assigned randomly to either the vestibular exercise or placebo exercise group. The randomization schedule is generated using a computer program for 2-sample randomization. The sequence was not concealed from the investigator who obtained consent from the subjects and supervised the exercises (SJH). The group assignment (vestibular exercise or placebo exercise) was concealed from the participants and from the investigator who performed the outcome measures. The vestibular exercise group practiced exercises that consisted of adaptation exercises and eye-head exercises to targets (Table 1), which were designed to improve gaze stability 16. They also performed gait and balance exercises. The placebo exercise group performed exercises designed to be 'vestibular-neutral'.
Interventions
OTHERControl exercises
saccadic eye movements against a plain background; no head movements
adaptation and substitutin exercises encorporating retinal lsip and head movements
Sponsors
National Institute on Deafness and Other Communication Disorders (NIDCD)
Emory University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Subject)
Eligibility
Sex/Gender
ALL
Age
18 Years to 80 Years
Healthy volunteers
Yes
Inclusion criteria
* Patient had to have either a unilateral vestibular or bilateral vestibular hypofunction defined as follows: Unilateral vestibular deficits were defined by a \> 25% difference in slow phase eye velocity between right and left sides on either the caloric or rotary chair test. Bilateral vestibular deficits were defined included refixation saccades made in response to unpredictable head thrusts to the right and left, a gain \< .1 on rotary chair step test and a peak slow phase eye movement of \<5 degrees/sec during irrigation of each ear on bithermal water caloric testing * Healthy subjects with normal vestibular function test results * must be able to complete DVA test
Exclusion criteria
* Patients with central lesions will be omitted from the study because vestibular adaptation or other compensatory mechanisms may be compromised and * Patients with visual acuity when the head is stationary of 20/60 or worse. * Patients on medication that suppress or facilitate vestibular function will not be excluded from the study but data will be analyzed to assess the effect of medication. * Patient who do not understand the purpose of the study and what it involves
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in Visual Acuity During Head Movement From Baseline to Discharge | pre-intervention and at discharge | visual acuity is measured using a computerized system first with the head stationary and then with the head moving in yaw plane. Head velocity is measured using a rate sensor and optotype is displayed only when head velocity is between 120 and 180 degrees per second. The change in visual acuity was calculated from subtracting the discharge measurement from the baseline measurement (pre-intervention). |
| Subjective Complaints: (All Pre- and Post-intervention): | pre-intervention, 2 weeks, 4 weeks and at discharge | questionnaire |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Symptoms Intensity for Dizziness, Oscillopsia, Disequilibrium | pre-intervention, 2 weeks, 4 weeks and at discharge | visual analoque scales |
| Balance and Gait | pre-intervention, 2 weeks, 4 weeks and at discharge | gait speed |
| Disability Scale | pre-intervention, 2 weeks, 4 weeks and at discharge | questionnaire |
| Eye Movements: Scleral Search Coil | pre- and post-treatment | eye movements are measured by having the participant sit within an electromagnetic field while wearing a scleral coil (like a contact lens but only in contact with the sclea, not the cornea); te coil moves with eye movement and distorts the electrimagnetic field |
| Fall Risk (Dynamic Gait Index) | pre-intervention, 2 weeks, 4 weeks and at discharge | performance test |
| Activities Specific Balance Confidence Scale | pre-intervention, 2 weeks, 4 weeks and at discharge | questionnaire |
Countries
United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Exercises for Gaze Stabilization Experimental group performed gaze stabilization exercises: adaptation and substitution exercises encorporating retinal slip and head movements | 13 |
| Control Exercises Saccadic eye movements against a Ganzfeld to prevent retinal slip error signal; no head movements | 10 |
| Total | 23 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| Overall Study | Ten participants were entered into the c | 0 | 2 |
Baseline characteristics
| Characteristic | Exercises for Gaze Stabilization | Control Exercises | Total |
|---|---|---|---|
| Age, Categorical <=18 years | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical >=65 years | 7 Participants | 5 Participants | 12 Participants |
| Age, Categorical Between 18 and 65 years | 6 Participants | 5 Participants | 11 Participants |
| Age, Continuous | 65.2 years STANDARD_DEVIATION 16.5 | 64.9 years STANDARD_DEVIATION 16.2 | 65.1 years STANDARD_DEVIATION 16.3 |
| Region of Enrollment United States | 13 participants | 10 participants | 23 participants |
| Sex: Female, Male Female | 9 Participants | 6 Participants | 15 Participants |
| Sex: Female, Male Male | 4 Participants | 4 Participants | 8 Participants |
| Visual acuity during head movements | .372 LogMAR STANDARD_DEVIATION 0.155 | .323 LogMAR STANDARD_DEVIATION 0.117 | .348 LogMAR STANDARD_DEVIATION 0.136 |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | — / — | — / — |
| other Total, other adverse events | 0 / 13 | 0 / 8 |
| serious Total, serious adverse events | 0 / 13 | 0 / 8 |
Outcome results
Primary
Change in Visual Acuity During Head Movement From Baseline to Discharge
visual acuity is measured using a computerized system first with the head stationary and then with the head moving in yaw plane. Head velocity is measured using a rate sensor and optotype is displayed only when head velocity is between 120 and 180 degrees per second. The change in visual acuity was calculated from subtracting the discharge measurement from the baseline measurement (pre-intervention).
Time frame: pre-intervention and at discharge
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Exercises for Gaze Stabilization | Change in Visual Acuity During Head Movement From Baseline to Discharge | 0.198 LogMAR | Standard Deviation 0.101 |
| Control Exercises | Change in Visual Acuity During Head Movement From Baseline to Discharge | .296 LogMAR | Standard Deviation 0.122 |
Primary
Subjective Complaints: (All Pre- and Post-intervention):
questionnaire
Time frame: pre-intervention, 2 weeks, 4 weeks and at discharge
Secondary
Activities Specific Balance Confidence Scale
questionnaire
Time frame: pre-intervention, 2 weeks, 4 weeks and at discharge
Secondary
Balance and Gait
gait speed
Time frame: pre-intervention, 2 weeks, 4 weeks and at discharge
Secondary
Disability Scale
questionnaire
Time frame: pre-intervention, 2 weeks, 4 weeks and at discharge
Secondary
Eye Movements: Scleral Search Coil
eye movements are measured by having the participant sit within an electromagnetic field while wearing a scleral coil (like a contact lens but only in contact with the sclea, not the cornea); te coil moves with eye movement and distorts the electrimagnetic field
Time frame: pre- and post-treatment
Secondary
Fall Risk (Dynamic Gait Index)
performance test
Time frame: pre-intervention, 2 weeks, 4 weeks and at discharge
Secondary
Symptoms Intensity for Dizziness, Oscillopsia, Disequilibrium
visual analoque scales
Time frame: pre-intervention, 2 weeks, 4 weeks and at discharge