Framework to generate perfusion map from CT and CTA images in patients with acute ischemic stroke: A longitudinal and cross-sectional study

Chayanin Tangwiriyasakul; Pedro Borges; Stefano Moriconi; Paul Wright; Yee-Haur Mah; James Teo; Parashkev Nachev; Sebastien Ourselin; M. Jorge Cardoso

arXiv · 2404.04025

Framework to generate perfusion map from CT and CTA images in patients with acute ischemic stroke: A longitudinal and cross-sectional study

Chayanin Tangwiriyasakul·Pedro Borges·Stefano Moriconi·Paul Wright·Yee-Haur Mah·James Teo·Parashkev Nachev·Sebastien Ourselin·M. Jorge Cardoso

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Abstract

Stroke is a leading cause of disability and death. Effective treatment decisions require early and informative vascular imaging. 4D perfusion imaging is ideal but rarely available within the first hour after stroke, whereas plain CT and CTA usually are. Hence, we propose a framework to extract a predicted perfusion map (PPM) derived from CT and CTA images. In all eighteen patients, we found significantly high spatial similarity (with average Spearman's correlation = 0.7893) between our predicted perfusion map (PPM) and the T-max map derived from 4D-CTP. Voxelwise correlations between the PPM and National Institutes of Health Stroke Scale (NIHSS) subscores for L/R hand motor, gaze, and language on a large cohort of 2,110 subjects reliably mapped symptoms to expected infarct locations. Therefore our PPM could serve as an alternative for 4D perfusion imaging, if the latter is unavailable, to investigate blood perfusion in the first hours after hospital admission.

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Chayanin Tangwiriyasakul, Pedro Borges, Stefano Moriconi, Paul Wright, Yee-Haur Mah, James Teo, Parashkev Nachev, Sebastien Ourselin, M. Jorge Cardoso. 2024-04-05. Framework to generate perfusion map from CT and CTA images in patients with acute ischemic stroke: A longitudinal and cross-sectional study. https://arxiv.org/abs/2404.04025

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