ABSTRACT NUMBER: ESOC2026A2501 EFFECT OF PARENCHYMAL FLUID-ATTENUATED INVERSION RECOVERY HYPERINTENSITY ON OUTCOME AMONG ISCHEMIC STROKE PATIENTS TREATED WITH TENECTEPLASE

Abstract Background and aims Acute ischemic stroke (AIS) patients with parenchymal FLAIR hyperintensity have been shown to have a poor outcome following intravenous thrombolysis (IVT) with alteplase. Our aim was to assess among patients treated with tenecteplase the impact of parenchymal FLAIR hyperintensity on efficacy and safety outcome. Methods We conducted a retrospective analysis of the TETRIS registry, including all patients who underwent a baseline brain MRI scan. The primary outcome was the three-month modified Rankin Scale (mRS) score. We used adjusted ordinal logistic regression to compare the three-month functional outcomes between FLAIR-positive and FLAIR-negative patients (ordinal analysis), and analysed parenchymal haemorrhage (PH) using adjusted logistic regression. Dose–response relationships were assessed for FLAIR burden (categorised as ≤50%, >50% and <100%, or 100%) and intensity (negative, discrete, or marked) using linear trend analyses. Results We included 1706 patients with baseline brain MRI. Of these, 189 patients (11%) had a FLAIR-positive infarct. Following adjustment, FLAIR positivity was associated with a poorer 3-month functional outcome (OR 1.59 [1.21–2.10], P<0.01), though there was no significant increase in parenchymal haemorrhage (OR 1.14 [0.72–1.83], P=0.56). Linear trend analyses revealed that an increase in both FLAIR burden (OR per category: 1.19 [1.03–1.38], P=0.02) and FLAIR intensity (OR per category: 1.34 [1.13–1.60], P=0.001) were independently associated with a poorer functional outcome. Conclusions Parenchymal FLAIR hyperintensity is associated with worse functional outcome in a dose-dependant manner without excess hemorrhagic risk. However, further studies are needed to assess whether IVT is beneficial for these patients. Conflict of interest Nicolas Laurent Plançon : no disclosure. Angélique Bergnon : no disclosure. Guillaume Turc : lecturing fees from Guerbet France, consulting fees for Neurologica and AI-Stroke Nicolas Chausson : no disclosure. Stéphane Olindo : no disclosure. Gaultier Marnat : consulting fees from Stryker neurovascular, Microvention Europe (Terumo Neuro), Balt Extrusion, Sim and Cure and paid lectures for Medtronic, Wallaby Phenox, Bracco, Penumbra and Johnson & Johnson Pierre Seners : consulting fees from Boehringer Ingelheim. Fernando Pico : no disclosure. Sonia Alamowitch : consulting fees from Amgen, AstraZeneca, Boehringer Ingelheim, Pfizer Pharma GMBH ; funding from the Programme hospitalier de recherche Clinique, Boehringer Ingelheim and the DMU Neurosciences of APHP.Sorbonne Université. Gaspard Gerschenfeld : consulting fees from Truffle Capital, funding from the Programme hospitalier de recherche Clinique, Boehringer Ingelheim and the DMU Neurosciences of APHP.Sorbonne Université. Figure 1 - belongs to Results