3D Null Space Imaging: Nonlinear Magnetic Encoding Gradients Designed Complementary to 3D Coil Sensitivity Profiles for Rapid Volume Imaging

Leo K. Tam¹, Jason P. Stockmann¹, Gigi Galiana², Dana C. Peters², R. Todd Constable²

Recent nonlinear gradient encoding strategies have demonstrated highly accelerated parallel imaging for reconstruction of a single slice. In the present study, we explore the unique 3D spatial localization available to spherical harmonic encoding gradients. To design the encoding gradients, the Null Space Imaging (NSI) strategy is used to create readout gradients complementary to the receiver coil sensitivities. As a first approach to nonlinear gradient projection imaging, the proposed method demonstrates the benefits of coil complementarity and reduced dB/dt extend to volume imaging.