Patent ID: 7252004
Filing Date: 2007-08-07
Classification: A61B,G01N,G01S

Abstract:
1. An imaging method using shear waves for observing a diffusing viscoelastic medium containing particles that reflect ultrasound compression waves, said method comprising: a) an excitation step during which an elastic shear wave is generated in the viscoelastic medium; b) an observation step during which the propagation of the shear wave is observed simultaneously at a multitude of points in an observation field in the viscoelastic medium, this observation step comprising the following substeps: c) at least one processing step during which: the method further comprising: during the excitation step a) the elastic shear wave is caused to be generated by causing at least one focused ultrasound wave to be emitted into the viscoelastic medium by said array of transducers, the focusing and the timing of said focused ultrasound wave, and the timing of said unfocused ultrasound wave being adapted so that at least some of said unfocused ultrasound waves penetrate into the observation field while the shear wave is propagating in the observation field, for at least some of the unfocused ultrasound wave emissions.