A method for correcting a map-B0 to chemical shifts, magnetic resonance apparatus and computer program

A method for correcting a magnetic means (17) measured, deviations from a nominal field strength in the homogeneous region of the magnetic resonance device (17) described by deviations from a nominal Larmor frequency for bonded in water protons, the deviations containing as Larmorfrequenzwerte for different image points B0 field map (1 ) in terms of chemical shifts of the magnetic resonance frequencies, the B0 field map (1) was taken up at least partially in non in-phase spins of the fat and water protons, the B0 field map (1) by means of the differences of the Larmorfrequenzwerte of adjacent pixels of the B0 field map (1) evaluating segmentation criterion in at least two contiguous, particularly at least two pixels containing clusters (3, 4, 5, 6, 8, 9, 10, 11) which are separated by a jump of the Larmorfrequenzwerte, is segmented, whereby for each cluster (3, 4, 5, 6, 8, 9 , 10, 11) decided on the basis of a smoothness criterion and a compactness criterion, whether containing a majority bound in fat protons cluster (6) acts, wherein the majority bound in fat protons containing identified cluster (6, 9, 10) by lowering Larmorfrequenzwerte of the difference between the nominal Larmor frequency for water protons in bound and the corresponding nominal Larmor frequency for fat protons bound to be corrected.