Abstract
BACKGROUND AND PURPOSE: We evaluated agreement and performance of non-contrast head-computerized tomography (NCHCT) and CT-perfusion (CTP) in identifying large core infarct in acute ischemic stroke (AIS) due to large vessel occlusion (LVO) undergoing endovascular therapy (EVT), using MRI as reference. METHODS: From our prospective multicenter registry, we identified patients with LVO-AIS due to internal carotid artery or middle cerebral artery M1occlusions who underwent EVT between 2017 and 2024. Final infarct volume (FIV) was defined using 24-48 h post-EVT diffusion-weighted imaging magnetic resonance imaging (MRI-FIV). To limit infarct growth bias, only patients with CTP-to-EVT start time <3 h were included. Large core infarct was defined at FIV thresholds: 50, 70, and 100 mL. The primary outcome was agreement between NCHCT and CTP in identifying large core infarct using kappa-statistics. Large core was considered if NCHCT-ASPECTS<6 or rCBF<30% volume>70 mL on CTP (RAPID/Viz.AI). Secondary outcomes included classification accuracy of each modality relative to MRI-FIV using the area under the receiver operating characteristic curve (AUC-ROC). Sensitivity analyses were performed in subgroups with TICI 2c-3 and cases processed by RAPID. RESULTS: Among 241 EVT-treated LVO-AIS patients, median NIHSS was 15 [IQR: 10-20], MRI-FIV 13.8 Ml [IQR: 5-41.0], ASPECTS 8 [IQR: 7-10], and CTP-predicted core 8 mL [IQR: 0-31.0]. CTP and NCHCT showed slight agreement in identifying large core (κ = 0.192) and weak-to-acceptable discrimination for identifying large core infarcts (AUC-ROC: 0.61-0.72 across MRI-FIV thresholds). Both modalities showed limited predictive ability for 90-day functional independence (AUC-ROC: 0.63-0.65). Similar findings were observed in sensitivity analyses. CONCLUSIONS: Among LVO-AIS EVT-treated patients, NCHCT and CTP demonstrated slight agreement in classifying small versus large core, and neither technique was effective at predicting FIV or clinical outcomes.