Full‐brain coverage and high‐resolution imaging capabilities of passband b‐SSFP fMRI at 3T

Passband balanced-steady-state free precession (b-SSFP)fMRI is a recently developed method that utilizes the passband(flat portion) of the b-SSFP off-resonance response to measureMR signal changes elicited by changes in tissue oxygenationfollowing increases in neuronal activity. Rapid refocusing andshort readout durations of b-SSFP, combined with the relativelylarge flat portion of the b-SSFP off-resonance spectrum allowsdistortion-free full-brain coverage with only two acquisitions.This allows for high-resolution functional imaging, without thespatial distortion frequently encountered in conventional high-resolution functional images. Finally, the 3D imaging compati-bility of the b-SSFP acquisitions permits isotropic-voxel-sizehigh-resolution acquisitions. In this study we address some ofthe major technical issues involved in obtaining passband b-SSFP-based functional brain images with practical imaging pa-rameters and demonstrate the advantages through breath-holding and visual field mapping experiments. Magn ResonMed 59:1099 –1110, 2008.