Blood-nulling versus tissue-suppression: Enhancing integrated VASO and perfusion (VAPER) contrast for laminar fMRI

Motivation: CBV and CBF based layer fMRI sequence methods suffer from relatively low sensitivity. Goal(s): We aim to induce addtional CBV sensitivity through MT to boost overall VAPER-fMRI sensitivity. Approach: We explored an innovative application of MT to induce a tissue-suppression-based VASO effect and integrate it with the VAPER technique. Results: Both theoretical and experimental evaluation demonstrated approximately 30% enhancement in VAPER sensitivity with MT application compared to the original VAPER without MT. Impact: We proposed an innovative MT-enhanced VAPER imaging sequence for layer fMRI that enhances sensitivity by 30% compared to traditional VAPER without MT, while maintaining superior laminar specificity without increasing acquisition time.