Multi-shot echo planar imaging using reordered segments and rf excitation pulse phase and slice profiles matched across interleaves
AssigneeThe General Hospital Corporation
InventorsJonathan R. Polimeni, Thomas Witzel
Life of this patent
Estimating the term…
Abstract
Described here are systems and methods for producing images with a magnetic resonance imaging (“MRI”) system using a high-resolution, motion-robust, artifact-free segmented echo planar imaging (“EPI”) technique. In particular, a fast low angle excitation echo planar imaging technique (“FLEET”) using variable flip angle (“VFA”) radio frequency (“RF”) excitation pulses that are specifically designed to have a flat magnitude and phase profile across a slice for a range of different flip angles.
Claims11
A method for producing an image of a subject using a magnetic resonance imaging (MRI) system, the steps of the method comprising:
- (a) acquiring k-space data from a slice in a subject using the MRI system to perform a pulse sequence that includes:
- a multi-shot variable flip angle (VFA) radio frequency (RF) excitation that excites spins in the slice and comprises a plurality of different RF excitation pulses each having a flip angle not greater than 90 degrees;
- a multi-shot echo planar imaging (EPI) data acquisition that acquires k-space data after each RF excitation pulse by sampling magnetic resonance signals generated by the excited spins in a plurality of different interleaved segments of k-space;
- (b) reconstructing an image of the subject from the acquired k-space data;
- and
- wherein each of the plurality of different RF excitation pulses is designed such that a slice profile and through-plane phase of the plurality of different RF excitation pulses are matched for each of the different interleaved segments of k-space.
Dependencies are inferred from the claim text.