Abstract Number: Esoc2026ys78 Lesion-Symptom and Network Mapping of Stroke-Related Dizziness: Secondary Analysis From the Inspire-TMS Trial

Abstract Background and aims Dizziness is a common and debilitating neurological symptom among patients visiting the emergency department (ED). Possibly because acute dizziness caused by ischemic stroke is not captured by standard stroke severity assessment tools such as the NIHSS, its neuroanatomical basis, especially cortical contributions, remains understudied. Methods This retrospective analysis included patients with acute ischemic stroke from the randomized controlled INSPiRE-TMS trial. All patients underwent MRI within seven days of stroke onset. Dizziness was evaluated by study personnel and defined as a sensation of disturbed spatial orientation. Lesion network mapping (LNM) was applied to identify associations between lesion location, connectivity, and dizziness. Results A total of 484 patients were included; 32% (n=157) reported dizziness at stroke onset. Lesions were stratified as supratentorial if confined to the cerebral hemispheres, diencephalon, or basal ganglia (n=347) and as infratentorial if involving the brainstem or cerebellum (n=137). Notably, 22% (n=77/347) of patients with supratentorial stroke reported dizziness. In patients with exclusively supratentorial lesions, LNM demonstrated statistically significant associations between the connectivity to occipital cortical regions and dizziness, including the lingual and fusiform gyri (Figure). These findings remained consistent in sensitivity analyses using LNM with lesions derived from an alternative MRI preprocessing pipeline. In post hoc analyses, patients were stratified into spinning/rotational vertigo (n=14) and swaying dizziness (n=40) based on ED records; LNM results in both subcohorts were consistent with the main findings. Overall, stratified LNM by lesion location and dizziness subtype highlighted key cortical contributions to stroke-related dizziness, likely via disruption of networks involving higher-order visual cortices. Conflict of interest The author(s) declare the following potential conflicts of interest concerning the research, authorship, and/or publication of this article: Y.T, U.T, A.S.R., M.A, A.Kh, and A.Ku report no disclosures. AKh reports compensation from Bayer for consultant services. ME reports grants from Bayer, Ipsen and fees for lectures and/or consulting paid to the Charité from Amgen, AstraZeneca, Bayer Healthcare, Boehringer Ingelheim, BMS, Daiichi Sankyo, Sanofi, and Pfizer, all outside of the submitted work. H.J.Audebert reports having received fees from Boehringer Ingelheim, Roche and Novo Nordisk, and also from Pfizer, BMS, Astra, Lilly, Novartis, Bayer and EVER Pharma. Figure 1 - belongs to Results