ABSTRACT NUMBER: ESOC2026A1949 EEG FOR EARLY DETECTION OF INTRACEREBRAL HAEMORRHAGE

Abstract Background and aims Prehospital intracerebral haemorrhage (ICH) detection could facilitate early blood pressure management and reduce treatment delays. Low-density electroencephalography (EEG) is a promising tool for prehospital anterior circulation large vessel occlusion (LVO-a) stroke assessment, but it is unknown whether EEG can also be used to diagnose ICH. Methods Dry electrode 8-channel EEG recordings were obtained from patients with suspected stroke in pre- and in-hospital settings. Recordings were visually assessed, and patients were included if ≥10 seconds of clean EEG data were available. The pairwise-derived Brain Symmetry Index (pdBSI) was calculated for several frequency bands, and group differences were analyzed between patients with and without ICH. Diagnostic accuracy of the pdBSI was expressed as the area under the receiver operating characteristics curve (AUC), sensitivity, and specificity. Optimal cut-offs were determined as the highest sensitivity at a specificity of ≥70%. Results Of 1385 screened patients, 216 (16%) were eligible (median age 71 [IQR 61-79], 69% men, median NIHSS 1 [IQR 0-3]). Eleven patients (6%) had ICH (six deep, two lobar, three infratentorial). Other diagnoses included 9/216 (4%) LVO-a stroke, 86/216 (40%) non-LVO-a ischemic stroke, 31/216 (14%) a transient ischemic attack, and 79/217 (37%) a stroke mimic. The pdBSI in the theta and 1-18 Hz band were statistically significantly higher in the ICH group compared to the non-ICH group (p<0.05); diagnostic accuracies for ICH detection showed AUCs of 0.71 (sensitivity 55%; specificity 86%) and 0.74 (sensitivity 82%; specificity 71%), respectively (Figure 1). Conclusions EEG holds promise to diagnose ICH in the prehospital setting. Conflict of interest Kars R. Tjepkema: nothing to disclose. Eva A. Groenendijk: nothing to disclose. Monique Theunissen: nothing to disclose. Jonathan M. Coutinho received unrelated research support from Bayer and AstraZeneca (all fees were paid to his employer), and is co-founder and shareholder of TrianecT. Henk A. Marquering is cofounder and shareholder of Nicolab, TrianecT, and inSteps. Maritta N. van Stigt: nothing to disclose. Data used for this study was collected with funding from the Dutch Heart Foundation, Health~Holland (Amsterdam UMC TKI-PPP grant), and an unrestricted research grant from Medtronic. Figure 1 - belongs to Results