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A complex subtraction methed was devetoped to accurately measure moduiation transfer functions ( MTFs ) in positive and negative frequencies of magnetic resonance images ( MRD ． The MTF was calculated from thc line spread function ， which was obtained with an original phantom by a process of subtraction of thc complex images ． The MTF in conventkmal spin − echo ( SE ) and Turbo SE ， in which cffective echo time was set at the first ecllo ， were evaluated by changing the T20f lhe p ． hantonl in the frequency − and phase −encod − ing directions ． MTFs indicaIed the characteristics of the k − spa 〔： e trajectory for each pu 且 se sequence ． Using this method ， Ihe influences of image nonuniformiIy and unneccssary artifacts could be eliminated ． Analy − sis of the MTF with thc complex subtraction method made it possible 竃o obtain more detailTegarding the resolution properties c) f MRI ．