GRAPPA Operator for Wider RadiaL Band (GROWL)

Wei Lin¹, Feng Huang¹, Yu Li¹, Charles Saylor¹, Arne Reykowski¹

A self-calibrated parallel imaging reconstruction method is proposed for azimuthally undersampled radial dataset. GRAPPA extrapolation operators were used to widen each radial view into a band consisting of several parallel lines, followed by a standard regridding procedure. Self-calibration is achieved by regridding central k-space region, where Nyquist criterion is satisfied, to a rotated Cartesian grid. Applying the proposed reconstruction method to in vivo radial gradient echo images demonstrated a removal of most streaking artifacts at data reduction factors R = 4 and 8, using an eight-element coil array.