Gregory R. Lee1, Jean Tkach1, Mark Griswold1,2
1Department of Radiology, Case Western Reserve University, Cleveland, OH, United States; 2Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States
A method to perform multi-echo BOLD functional MRI using an undersampled, multishot 3D radial trajectory is demonstrated. The proposed view-ordering scheme is a 3D analog of bit-reversed view ordering and allows reconstruction at power of 2 undersampling factors (2,4,8,16). Aliasing artifacts are periodic in time and can be removed via UNFOLD. Whole brain images were reconstructed at five echo times (TE=7.3, 16.1, 24.9, 33.6 and 42.4 ms) while maintaining a temporal resolution of 798 ms / volume. The multiple echoes can used to create dynamic T2* maps and may be combined via weighted summation (optimizing sensitivity over multiple T2* values).