vHIT Testing for Presentation of Dizziness at a Comprehensive Stroke Center

Study Overview
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Brief Summary
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The purpose of this study is to evaluate the sensitivity and specificity of the video head impulse test (vHIT) device, when implemented in the acute ED setting to identify acute ischemic stroke or central pathology vs peripheral vestibular dysfunction in patient's presenting with vertigo. This study will evaluate the implementation of the device, consistency with current diagnostic standards, unnecessary administration of antithrombolytics and will further study the reduction in hospital admissions and overall healthcare costs.

Detailed Description
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In the proposed study, subjects admitted to the Emergency Department (ED) with symptoms of dizziness, concerning for an acute ischemic stroke, will undergo routine triage (bedside neurologic examination, head impulse testing, CT scan) and will then be tested with a vHIT device to attempt to further identify the cause of dizziness, after standard of care testing has been performed. The clinician performing the vHIT will be blinded to the result of the CT scan before entering their report.

Official Title
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Is Video Head Impulse Testing a Safe, Reliable and Cost Effective Method of Assessment of Patients Presenting for Dizziness at a Comprehensive Stroke Center?

Conditions
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Dizziness; Syndrome, Stroke, Acute, Vertigo, Vertigo, Peripheral, Dizziness

Intervention / Treatment
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* Device: Video Head Impulse Testing
* Other: Standard of care neurologic evaluation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adults between the ages of 18-90 Admitted to the MUSC ED with symptomatic dizziness, concerning for a stroke vs peripheral vestibular dysfunction. Exclusion Criteria: Prisoners COVID + Cognitively Impaired Individuals

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 90 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: vHIT testing<br>For the research portion of this study, following standard of care examinations listed above, the patient would have a vHIT headset placed on their head for approximately 3-5 minutes to test if they exhibit corrective saccadic movements and to measure gain reduction to identify vestibular hypofunction. During vHIT testing a commercially available mono-ocular video oculography system will be donned on the patient. Subjects will be instructed to maintain fixation at a target from 1 m distance. A study team member will deliver at least 5 head impulses per side in the horizontal and vertical planes with unpredictable timing and direction. A neurotologist will then evaluate the VOR gain or the ratio of eye velocity over-head velocity. The presence of refixation (catch-up) saccades, either overt or covert, will be evaluated by the study team. In line with previous literature, the vHIT testing will be considered to be abnormal if VOR gain is <0.8 in the presence of refixation saccades . | Device: Video Head Impulse Testing<br>* During vHIT testing a commercially available mono-ocular video oculography system will be donned on the patient. (Interacoustics EyeSeeCam vHIT 3rd Generation Tests: VOR of lateral, RALP, & LARP canals. SW: 3rd generation VE525 software. HW: laptop PC, lightweight monocular video goggles). Subjects will be instructed to maintain fixation at a target from 1 m distance. A study team member will deliver at least 5 head impulses per side (10-20° angle, duration 150-200 ms, peak velocity of >150°/s) in the horizontal and vertical planes with unpredictable timing and direction. A neurotologist will then evaluate the VOR gain or the ratio of eye velocity over-head velocity. The presence of refixation (catch-up) saccades, either overt or covert, will be evaluated by the study team. In line with previous literature, the vHIT testing will be considered to be abnormal if VOR gain is <0.8 in the presence of refixation saccades .<br>Other: Standard of care neurologic evaluation<br>* A standard neurologic evaluation will be performed including a National Institute of Health Stroke Scale and imaging if symptoms and NIHSS warrant.<br>|
| Active Comparator: Standard of Care<br>The intervention group will be compared to standard of care provided to patients currently admitted for dizziness. Standard of care includes National Institute of Health Stroke Scale evaluation, evaluation by a neurologist, and a CT scan or MRI if warranted. | Other: Standard of care neurologic evaluation<br>* A standard neurologic evaluation will be performed including a National Institute of Health Stroke Scale and imaging if symptoms and NIHSS warrant.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Sensitivity & Specificity of vHIT device | Sensitivity and specificity of the vhit to detect peripheral vestibular dysfunction in an acute presentation of vertigo | This will be performed once all results are compiled, not to exceed 90 days after study completion. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Time to perform testing | The time it takes to perform vHIT testing on a participant admitted for dizziness in the hospital environment. | From time the study team member arrives to patient's location until vHIT testing is complete, not to exceed 1 hour. | 
| Predictive Value | We will measure positive predicitive value of vHIT to determine peripheral vestibular involvement in a participant who presents with dizziness. | At the time results are compared from vHIT testing to CT scan, not to exceed 30 days post testing. | 
| Cost Analysis | We will examine the cost reduction that would have occured if vhit was incorporated in decision making for stroke workup and/or hospital admission | This will be performed once all results are compiled, not to exceed 90 days after study completion. |