Abstract: This method, for determining the local intensity (I0) of an acoustic field propagating in a target region of a soft solid, at a position located within said target region, includes at least the following steps: determining (102) a value of an ultrasound attenuation coefficient (?) of the soft body in the target region; determining (104) a value of the shear modulus (?) of the soft body in the target region; determining (106) a value of the speed of sound (c) in the target region of the soft body; and building (110), with the values determined in steps a), b) and c), a viscoelastic model (M) of a steady-state displacement induced by an acoustic field having a time invariant shape or a viscoelastic model of a difference between two steady-state displacements induced by an acoustic field having a time invariant shape.

Abstract: This method, for determining the local intensity (I0) of an acoustic field propagating in a target region of a soft solid, at a position located within said target region, includes at least the following steps: determining (102) a value of an ultrasound attenuation coefficient (?) of the soft body in the target region; determining (104) a value of the shear modulus (?) of the soft body in the target region; determining (106) a value of the speed of sound (c) in the target region of the soft body; and building (110), with the values determined in steps a), b) and c), a viscoelastic model (M) of a steady-state displacement induced by an acoustic field having a time invariant shape or a viscoelastic model of a difference between two steady-state displacements induced by an acoustic field having a time invariant shape.

Abstract: This method for imaging in real time the propagation of a mechanical wave in an acoustically propagative medium comprises steps of: a) emitting (1000) a mechanical wave in an acoustically propagative medium, using an acoustic source being placed in an emission region of the acoustically propagative medium, b) measuring (1002) voltage signal waveform values at a reception region, using an acoustic measurement unit; c) calculating (1004) acoustic field values in the acoustically propagative medium, between the emission region and the reception region, using a reconstruction algorithm implemented in a signal processing unit, and the signal waveform values measured during step b) d) generating an image, using an image generation device and using the calculated acoustic field values.

Abstract: Method for generating a shear wave in a target region of a soft solid, includes the following steps: a) generating at least two shear waves with a first and a second source of shear waves in the target region; b) detecting a propagation pattern of the shear wave in the target region with a detector unit including a row of ultrasonic transducers aligned on a first direction perpendicular to a detection direction of each or a single ultrasonic transducer movable along a first direction perpendicular to its detection direction; c) proceeding to a time reversal of the detected propagation pattern; and d) submitting the target region to an inverted excitation set of forces based on the temporally inverted propagation pattern. During step b), a first propagation pattern is detected when only the first source is active and a second propagation pattern is detected when only the second source is active.

Abstract: This shear wave imaging method, for collecting information on a target region (R) of a soft solid (S), comprises at least the steps a) of generating at least one shear wave (SW) in the target region, and b) of detecting a propagation pattern of the shear wave in the target region. Step a) is realized by applying to particles of the target region (R) some Lorentz forces resulting from an electric field (E) and from a magnetic field (B). At least one of the electric field (E) and the magnetic field (B) is variable in time, with a central frequency (fo) between 1 Hz and 10 kHz. Alternatively, both the electric and magnetic fields (E, B) are variable in time, with a central difference frequency (?fo) between 1 Hz and 10 kHz. The shear wave imaging installation comprises a first system (4, 7) for generating at least one shear wave (SW) in the target region (R) and a second system (10) for detecting a propagation pattern of the shear wave.

Abstract: Method for generating a shear wave in a target region of a soft solid, includes the following steps: a) generating at least two shear waves with a first and a second source of shear waves in the target region; b) detecting a propagation pattern of the shear wave in the target region with a detector unit including a row of ultrasonic transducers aligned on a first direction perpendicular to a detection direction of each or a single ultrasonic transducer movable along a first direction perpendicular to its detection direction; c) proceeding to a time reversal of the detected propagation pattern; and d) submitting the target region to an inverted excitation set of forces based on the temporally inverted propagation pattern. During step b), a first propagation pattern is detected when only the first source is active and a second propagation pattern is detected when only the second source is active.

Abstract: This shear wave imaging method, for collecting information on a target region (R) of a soft solid (S), comprises at fi least the steps a) of generating at least one shear wave (SW) in the target region, and b) of detecting a propagation pattern of the shear wave in the target region. Step a) is realized by applying to particles of the target region (R) some Lorentz forces resulting from an electric field (E) and from a magnetic field (B). At least one of the electric field (E) and the magnetic field (B) is variable in time, with a central frequency (fo) between 1 Hz and 10 kHz. Alternatively, both the electric and magnetic fields (E, B) are variable in time, with a central difference frequency (?fo) between 1 Hz and 10 kHz. The shear wave imaging installation comprises a first system (4, 7) for generating at least one shear wave (SW) in the target region (R) and a second system (10) for detecting a propagation pattern of the shear wave.

Abstract: The invention relates to methods comprising a step consisting of determining the proportion and/or the level of T regulatory lymphocytes with a CD4+ CD8??low Foxp3neg phenotype specific for Faecalibacterium prausnitzii for (i) diagnosing, (ii) prognosing outcome of, or (iii) predicting the risk of developing, an inflammatory bowel disease in a patient. The invention also concerns the treatment of an inflammatory bowel disease. The invention further relates to the kits that are useful in the above methods for diagnosing/prognosing an inflammatory bowel disease, and in the treatment of an inflammatory bowel disease. In a particular embodiment, the inflammatory bowel disease is the Crohn's disease.

Abstract: A method for performing elastography is provided, comprising the following steps. First, emitting a first coded signal towards tissue and recording an echoed signal in response. Next, applying a strain on the tissue, such as a compression or an expansion. Then, emitting a second coded signal towards the tissue under strain, said second signal being a compressed (or stretched) version of the first emitted signal in the time domain, and recording an echoed signal in response. Then processing the second echoed signal by stretching (or compressing) it in the time domain by a factor matched to the compression (or stretching) factor that was applied to the second emitted signal. Finally, cross-correlating the first echoed signal and the processed second echoed signal to provide an elastographic image of said tissue. The method of the invention uses different emitted signals before and during strain applied to the tissue. The image quality in elastography can therefore be considerably improved.