3D
Variable density spiral (VDS)–“beachball” was designed and generated to cover
3D k-space efficiently. Beachball is obtained by rotating along one axis of a
2D VDS for various number of shots. Beachball was demonstrated in-silico by analyzing point spread
function and restrospective analysis of a in-vitro
water phantom. Reconstruction was done using NUFFT. Optimal gradient waveforms
were generated for beachball by using convex optimization formulations based on
the constraints of maximum gradient amplitude and slew rate. This
trajectory provides for smoother coverage and densely sampled at the centre of
k-space and allows implementation of silent MR.