CAIPI accelerated 3D bSSFP for laminar fMRI at 7T

Motivation: Conventional T2*-weighted BOLD fMRI based on EPI sequence is limited by geometric distortions and poor localization specificity, necessitating the development of alternative imaging methods. Goal(s): To develop a high-resolution, high-SNR, distortion-free non-BOLD fMRI method and validate its feasibility for task-based fMRI. Approach: Developing a 3D bSSFP sequence with 2D-CAIPI acceleration to acquire sub-millimetre resolution functional images, allowing comparison with BOLD fMRI. Results: Task-based bSSFP fMRI reveals a reasonable activation pattern, different from that of BOLD fMRI. Impact: This study integrates 3D bSSFP acquisition into task-based fMRI, employing 2D-CAIPI acceleration to enhance acquisition speed, and conducts a comparative analysis with BOLD fMRI, highlighting the superior spatial localization accuracy of bSSFP.