Albert Kir1, 2, Alan B. McMillan3, Rao P. Gullapalli1, 2, Joel M. Morris4
1Magnetic Resonance Research Center, University of Maryland, School of Medicine, Baltimore, MD, United States; 2Diagnostic Radiology and Nuclear Medicine, University of Maryland, School of Medicine, Baltimore, MD, United States; 3Radiology, University of Wisconsin Madison, School of Medicine and Public Health, Madison, WI, United States; 4Communication and Signal Processing Laboratory, University of Maryland, Baltimore County, Baltimore, MD, United States
Echo Planar Imaging (EPI) techniques have been traditionally used to perform functional magnetic resonance imaging (fMRI). Due to the issues of signal dropout and/or geometric distortion of EPI-based sequences, balanced steady-state free precession (bSSFP) techniques have been studied as a potential alternative for acquiring fMRI images with improved image signal and spatial resolution. However, depending on the distribution of field inhomogeneity, a bSSFP sequence exhibits geometrically-varying sensitivity to the BOLD signal. In this study, we have implemented a frequency modulated (FM) bSSFP approach to address this issue and demonstrate its application in high-resolution fMRI.