MR imaging with spiral acquisition

A magnetic resonance (MR) device comprising:

• at least one main magnet coil for generating a uniform, static magnetic field within an examination volume;
• gradient coils for generating switched magnetic field gradients in different spatial directions within the examination volume;
• at least one RF coil for generating RF pulses within the examination volume and/or for receiving MR signals from an object positioned in the examination volume;
• a control unit for controlling a temporal succession of the RF pulses generated by the at least one RF coil and the switched magnetic field gradients generated by the gradient coils;
• a video monitor;
• and
• a reconstruction unit for reconstructing a MR image from the received MR signals, wherein the MR device is arranged to perform the following steps:
• subjecting the object to an imaging sequence comprising at least one RF excitation pulse and sinusoidally modulated magnetic field gradients,
• selecting two or more spiral k-space trajectories, wherein each spiral k-space trajectory lies in a kx-ky plane and the origins of the spiral k-space trajectories are offset from each other in the kx and/or ky directions, wherein the offset spiral k-space trajectories are overlapping in a region around k-space origin;
• acquiring MR signals along the two or more spiral k-space trajectories;
• reconstructing an MR image from the acquired MR signals;
• and
• displaying the MR image on the video monitor.

A computer program stored on a non-transitory computer readable medium, to be run on a magnetic resonance (MR) device, which computer program comprises instructions for:

• generating an imaging sequence comprising at least one RF excitation pulse and sinusoidally modulated magnetic field gradients;
• selecting MR signals along two or more spiral k-space trajectories, wherein each spiral k-space trajectory lies in a kx-ky plane and the origins of the spiral k-space trajectories are offset from each other along a direction parallel with the kx-ky plane, wherein the offset spiral k-space trajectories are overlapping in a region around k-space origin;
• acquiring MR signals along the two or more spiral k-space trajectories;
• reconstructing an MR image from the acquired MR signals;
• and
• displaying the MR image.