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).