Maximum-Intensity projection on Non-Contrast CT in anterior stroke patients predicts ischemic core volume after mechanical thrombectomy: A retrospective, feasibility study.

Acute ischemic stroke (AIS) requires rapid intervention, with ischemic core volume assessment being critical for patients' selection in medical and endovascular treatments. Currently, perfusion CT (CTP) is often used for this purpose, but it requires additional contrast, radiation, and specialized software. This study explores the potential of 8 mm maximum-intensity projection (MIP) reformats of non-contrast CT (NCCT) as an alternative for ischemic core volume estimation. This retrospective study analyzed data from 42 patients with anterior circulation stroke and treated with mechanical thrombectomy between 2021 and 2022. Ischemic core volumes were measured using three methods: manual segmentation of MIP-CT, automated CTP, and follow-up CT scans for final infarct volume (FIV). Correlation and concordance between the methods were assessed using Kendall's tau correlation coefficient, Generalized Linear Models regression, and Bland-Altman plots. MIP-based ischemic core showed higher correlation coefficients with FIV (tau = 0.43) compared to CTP (tau = 0.39). Bland-Altman Analysis showed improved concordance between MIP and FIV, with more regular systematic bias compared to CTP. MIP also demonstrated greater sensitivity in detecting ischemic core, suggesting it may be more reliable than CTP for early stroke assessment. MIP on NCCT provides a reliable, contrast- and radiation-sparing method for ischemic core volume measurement in AIS patients, with performance metrics comparable and possibly superior to CTP in predicting final infarct volume. Further research is warranted to validate these findings in larger, prospective cohorts.