B0 field inhomogeneity estimation using internal phase maps from long single echo time mri acquisition

A medical imaging system comprising:

• a magnetic resonance (MR) imager;
• a processor;
• and
• a memory, the memory storing instructions that, when executed, are operable to:
• receive MR data from the MR imager;
• apply a transform to the MR data, wherein a result of the applying is an image space representation of the MR data;
• determine a wrapped phase map of the image space representation of the MR data;
• obtain an unwrapped phase map based on the wrapped phase map;
• scale the unwrapped phase map into a B0 field map, the scaling disregarding effects on the MR data by artifact sources secondary to B0 field inhomogeneities;
• reconstruct the MR image based on the MR data;
• correct the MR image based on the B0 field map;
• and
• output the MR image.

A non-transitory computer-readable medium storing processor-executable process steps, the process steps executable by a processor to cause a system to:

• receive clinical MR data from the MR imager;
• apply a transform to the clinical MR data, wherein a result of the applying is an image space representation of the clinical MR data;
• determine a wrapped phase map of the image space representation of the MR data;
• obtain an unwrapped phase map based on the wrapped phase map;
• scale the unwrapped phase map into a B0 field map according to a linear relationship between B0 and echo time;
• reconstruct the MR image based on the clinical MR data;
• correct the MR image based on the B0 field map;
• and
• output the MR image.