Method for Principal Frequency Magnetic Resonance Elastography Inversion

A magnetic resonance imaging (MRI) system, comprising:

• a magnet system configured to generate a polarizing magnetic field about at least a portion of a subject positioned in the MRI system;
• a plurality of gradient coils configured to establish a magnetic field gradient about at least a portion of the subject positioned in the MRI system;
• a radio frequency (RF) coil configured to apply an RF field to at least a portion of the subject and to receive magnetic resonance (MR) signals therefrom;
• a computer system programmed to:
• direct the plurality of gradient coils and the RF coil to perform a pulse sequence that acquires motion-encoded MR signals from the subject;
• reconstruct images from the acquired motion-encoded MR signals;
• produce a spatial frequency spectrum from the reconstructed images;
• calculate a principal frequency of the produced spatial frequency spectrum;
• and
• calculate a mechanical property of a tissue in the subject using the reconstructed wave images and the calculated principal frequency.