ABSTRACT NUMBER: ESOC2026YS182 IMAGING BIOMARKERS OF MICROVASCULAR DYSFUNCTION IN STROKE PATIENTS UNDERGOING REPERFUSION TREATMENT – AUTOMATIC QUANTIFICATION AND PROGNOSTIC EVALUATION

Abstract Background and aims Despite the high efficacy of mechanical thrombectomy (MT) in stroke patients with large-vessel occlusion, not all patients benefit equally from recanalization. Recent research indicates that unfavorable clinical outcomes may be caused by microvascular dysfunction associated with no-reflow, infarct growth, and hemorrhagic transformation of critically hypoperfused tissue. Advanced tracer-kinetic modelling of routine computed tomography perfusion (CTP) provides a promising avenue to establish prognostically relevant imaging biomarkers of microvascular dysfunction in stroke patients, such as blood brain barrier leakage or reduced oxygen extraction capacity. However, automated imaging solutions necessary for (cross-) validating these biomarkers in large scale datasets are not available. This study aims to bridge this gap by building an Open-source Automated Stroke Imaging Software (OASIS) to investigate imaging biomarkers of microvascular failure and their relationship with infarct growth, hemorrhagic transformation, and clinical outcomes after MT. In the long term, the project aims to provide the means for translational studies aimed at neurovascular protection in acute ischemic stroke patients. Methods OASIS will provide state-of-the-art automatic processing of raw multi-modal CT imaging data, generating maps of perfusion imaging biomarkers and lesion segmentations. The derivation cohort will consist of ~600 stroke patients treated with MT at our hospital. Imaging biomarkers of microvascular failure will be associated with clinical (mRS) and imaging outcomes (infarct growth, hemorrhagic transformation) using linear models. Validation will be conducted in external cohorts of large clinical consortia. Results Currently, a prototype of the software is being developed. Initial results of the derivation cohort will be presented at ESOC 2026. Conflict of interest Götz Thomalla received consultancy fees from Acandis, Boehringer Ingelheim, Bayer, and Portola, and fees as lecturer from Acandis, Alexion, Amarin, Bayer, Boehringer-Ingelheim, BMS/Pfizer, Daiichii Sankyo and Portola. He serves in the board of the TEA Stroke Study and of ESO. Nils Schweingruber is CEO of IDM gGmbH.