Mapping cerebrovascular reactivity and vascular lag in gliomas with multi-echo BOLD fMRI and breath-holding

Motivation: Cerebrovascular reactivity (CVR) with BOLD fMRI during breath-holding offers a feasible technique for examining neurovascular alterations in tumor-affected regions. However, this examination may have reduced accuracy due to breath-hold-induced artifacts. Goal(s): This study explores the use of multi-echo fMRI techniques to improve the accuracy and reliability of CVR mapping and vascular lag estimation in glioma patients. Approach: We employed optimized ME-fMRI procedures in 21 patients with diverse glioma characteristics, including lagged regression analysis, nuisance modeling with ME-ICA. Results: Our protocol robustly mapped reductions in CVR in all patients, and showed the vascular lag provides differential clinically valuable insights into tumor and peritumoral areas. Impact: This work present a robust and feasible multi-echo fMRI protocol with breath-holds that enhances cerebrovascular reactivity (CVR) mapping by obtaining complementary vascular lag maps, which offer critical insights into vascular delay and vasodilatory dynamics in glioma patients