ABSTRACT NUMBER: ESOC2026A2455 MRI VOLUMETRIC PARAMETERS OF ISCHEMIC LESIONS AND THE OCCURRENCE OF LATE SEIZURES AFTER ISCHEMIC STROKE

Abstract Background and aims Late epileptic seizures (LS) represent a significant complication of ischemic stroke and are associated with increased morbidity and mortality. The study aimed to evaluate the relationship between the occurrence of LS and MRI volumetric parameters of the ischemic lesion, hemorrhagic transformation, and blood–brain barrier (BBB) disruption. Methods This prospective, single-center study included patients with supratentorial acute ischemic stroke and no prior history of epilepsy. Patients were followed for 2 years for seizure occurrence. MRI with gadolinium contrast was performed 7–12 days after stroke onset. Volumes of the ischemic core (DWI hyperintensity), total stroke lesion (FLAIR hyperintensity), combined DWI/FLAIR lesion, hemorrhagic transformation, and BBB disruption (gadolinium enhancement) were quantified using an automated algorithm and compared between patients with and without LS. Results A total of 228 patients were included (39% women; median age 68 years; median NIHSS score 4). Late seizures occurred in 9 patients (4%), with a median latency of 384 days. Patients with LS had significantly larger ischemic lesion volumes on DWI (31.04 ml vs. 5.11 ml, p=0.01), FLAIR (91.24 ml vs. 8.72 ml, p=0.015), and combined DWI/FLAIR (93.26 ml vs. 10.67 ml, p=0.022). Among patients with hemorrhagic transformation, those with LS showed a significantly larger hemorrhage volume (14.3 ml vs. 2.16 ml, p=0.043). The volume of BBB disruption was higher in patients with LS, but this difference did not reach statistical significance. Conclusions Patients who developed late seizures after ischemic stroke had larger ischemic lesions, larger ischemic cores, and larger hemorrhagic transformation volumes. Conflict of interest Petr Jansky: nothing to disclose