Methods for fat quantification with correction for noise bias

A method for calculating a fat fraction for one or more voxels of interest using a magnetic resonance imaging (MRI) system, the method comprising the steps of:

• a) acquiring an image data set with the MRI system at an echo time, wherein the image data set includes a corresponding image signal value at each of a plurality of voxels;
• b) acquiring an in-phase image data set with the MRI system at a different echo time when fat and water are in-phase, wherein the in-phase image data set includes image signal values at each of the plurality of voxels;
• c) forming a normalized image data set by dividing image signal values in the image data set acquired in step a) by corresponding image signal values in the in-phase image data set acquired in step b);
• and
• d) calculating, for each voxel of interest, at least one of a fat fraction and a water fraction by solving a system of linear equations that relate a normalized signal value in the normalized image data set to the at least one of a fat fraction and a water fraction.