Abstract: The invention relates to a method of elastography whose diagnostic performance is improved in that the variation in time of the excursion whereby a region responds to excitation by mechanical oscillations is analyzed and the non-linear distortions are measured. Such distortions are a measure of the non-linear elastic properties of the region and constitute a diagnostically relevant item of information.

Abstract: The invention relates to a mammography accessory for MR elastography which is capable of generating longitudinal oscillations which extend in the longitudinal direction in the mammae of a patient to be examined. The examination time can thus be reduced while at the same time realizing a rendition of the mammae in transverse slice images which is acceptable to examiners.

Abstract: The invention relates to a mammography accessory for MR elastography which is capable of generating longitudinal oscillations which extend in the longitudinal direction in the mammae of a patient to be examined. The examination time can thus be reduced while at the same time realizing a rendition of the mammae in transverse slice images which is acceptable to examiners.

Abstract: MR elastography is a non-invasive imaging modality in which a visco-elastic region (such as the human breast) is excited by mechanical waves. Present-day approaches are based on transverse waves and on other assumptions which produce artefacts 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 visco-elastic 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.

Abstract: The invention relates to an imaging method for medical examinations, notably MR examinations, in which a set of measurement values is acquired from measuring points which are irregularly distributed in the frequency domain (or in the k-space). Before an image in the space domain is generated from these measurement values by a Fourier transformation, the measurement values must be weighted in dependence on the density of the measuring points in the frequency domain. To this end, the measurement values are weighted in conformity with the magnitude of the Voronoi cells.