| 摘要 |
PROBLEM TO BE SOLVED: To provide a magnetic resonance elastography method that is a non-invasive imaging modality in which a visco-elastic region (such as the human breast) is excited by mechanical waves. SOLUTION: Present-day approaches are based on transverse waves and on other assumptions which produce artifacts when there are longitudinal wave or reflections within that region. The invention is based on the insight that the results of the MRE measurement are the time-independent solution of the partial differential equations describing exactly the behavior of mechanical waves in viscoelastic material (even for longitudinal waves and in a reflecting environment). Therefore, Young's modulus contained in these equations can be calculated. Moreover, it is proposed to use (predominantly) longitudinal waves. Longitudinal waves are capable of penetrating the human breast, whereas transverse waves are not. COPYRIGHT: (C)2011,JPO&INPIT
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