Abstract DP079: Stroke in patients with neuro-vestibular presentation: experience from AVERT trial

Introduction: Diagnosing stroke in emergency department (ED) dizziness is challenging, where time-sensitive decisions are critical. Prospective data on disease prevalence, clinical findings, and diagnostic pitfalls remain limited. We report on cerebrovascular patients enrolled in the AVERT (Acute Video-oculography for Vertigo in Emergency Rooms for Rapid Triage) trial (ClinicalTrials.gov #NCT02483429). Methods: AVERT was a multicenter (n=5), parallel-design diagnostic strategy trial randomizing patients from 2018 to 2020. Patients presenting to the ED with acute- or recent- (<30 days) onset vestibular symptoms (dizziness, vertigo, unsteadiness) underwent structured evaluation using quantitative video-oculography (head impulse test, nystagmus, test of skew [HINTS] plus positional testing [Dix-Hallpike, supine roll]) and standardized neurological scores (National Institutes of Health Stroke Scale [NIHSS]). Those meeting inclusion criteria (presence of nystagmus or ataxia) were enrolled. The study team completed follow-ups at one week (repeat VOG, 3T brain MRI, neuro-vestibular specialist exam) and one, six months (phone call, medical record review). Gold standard diagnoses were determined by masked multidisciplinary panel review of all clinical and imaging data out to one month. Results: Of randomized subjects (n=130), 11% had a cerebrovascular cause (9 ischemic stroke, 4 TIA, 1 bleed)—3/10 strokes and 2/4 TIAs were misdiagnosed at one or more prior ED visits, and 3/9 ischemic strokes missed the tPA window from delay during the AVERT ED index visit (all had NIHSS≤1, so may not have been thrombolysis eligible). Among patients with strokes, most endorsed one or more non-otologic symptoms, but NIHSS scores were low (median 0.5, IQR 0-1, range 0-5) (Fig. 1/2). Only continuous dizziness was found, and 4 presented with isolated acute vestibular syndrome (only eye signs or gait unsteadiness); HINTS indicated a central cause in all 10 stroke cases (Fig. 3). Most lesions were small (<10mL, n=7/10); among 8 ischemic strokes undergoing acute MRI-DWI, 3 were falsely negative (38%) (Fig. 1). Conclusions: Vestibular strokes are difficult to diagnose, often with low NIHSS or false-negative early MRI, leading to diagnostic delays. Careful eye movement assessment (including HINTS) is essential to capture all strokes. These findings underscore the importance of integrating bedside neuro-vestibular assessment into acute stroke pathways to reduce misdiagnosis and treatment delays.