39 results about "Ultrasound scattering" patented technology

A method for characterizing ultrasound scatterers in a medium comprising providing ultrasound data representing a region of interest comprising a plurality of scatterers in a medium, the plurality of scatterers including clusters of scatterer sub-units, the scatterers having a physical property value to be estimated and the scatterer sub-units having at least one known physical parameter value; modelling the ultrasound data using an at least second order function of a spatial organization parameter defining the spatial organization of the scatterers; and estimating the physical property value of the scatterers from the modelled ultrasound data and the at least one known physical parameter of the sub-units by a regression of the spatial organization parameter as a function of frequency. A system for characterizing ultrasound scatterers is also included.

A treatment instrument system according to the present invention includes: an endoscope having a treatment instrument channel; an ultrasound probe inserted through the treatment instrument channel of the endoscope; an ultrasound observing apparatus having a blood flow display function and a distance measuring function; a treatment instrument having, at a distal end portion, an ultrasound scattering portion for scattering ultrasound; and an over tube having an endoscope insertion path through which the endoscope can be inserted and a treatment instrument insertion path through which the treatment instrument can be inserted, and having, at a distal end portion, an ultrasound scattering portion for scattering ultrasound.

A method for characterizing ultrasound scatterers in a medium comprises receiving ultrasound data representing a region of interest comprising a plurality of scatterers in a medium, the plurality of scatterers including aggregates of the scatterers. The ultrasound data is modeled data using an effective medium theory combined with the structure factor model, the structure factor model defining the spatial organization and concentration of the aggregates. The modeled ultrasound data is compared to theoretical data obtained with the effective medium theory combined with the structure factor model. From the comparison, dimensional data of the aggregates of the scatterers and the volume concentration of scatterers in the medium is determined.

Systems and methods for super-resolution ultrasound imaging using a windowed and generalized TR-MUSIC algorithm that divides the imaging region into overlapping sub-regions and applies the TR-MUSIC algorithm to the windowed backscattered ultrasound signals corresponding to each sub-region. The algorithm is also structured to account for the ultrasound attenuation in the medium and the finite-size effects of ultrasound transducer elements. A modified TR-MUSIC imaging algorithm is used to account for ultrasound scattering from both density and compressibility contrasts. The phase response of ultrasound transducer elements is accounted for in a PC-MUSIC system.

The velocity of fluids containing particles that scatter ultrasound can be measured by determining the Doppler shift of the ultrasound scattered by the particles in the fluid. Measuring fluid flow in cylindrical vessels such as blood vessels is an important use of Doppler ultrasound. This invention teaches using various configurations of cylindrical diffraction-grating transducers and cylindrical non-diffraction-grating transducers that suppress the Doppler shift from non-axial components of fluid velocity while being sensitive to the Doppler shift produced by axial velocity components. These configurations thus provide accurate measurement of the net flow down the vessel, even when the fluid flow is curved or not parallel to the vessel wall.

The present invention provides an acceleration and enhancement methods for ultrasound scatterer structure visualization. The method includes: obtaining an ultrasonic image, calculating all values of the ultrasonic signal points in each mth window centered at a nth signal point to obtain a plurality of original statistical values anxm, obtaining a plurality of mth statistical values by averaging value of original statistical values in the same window, calculating a plurality of mth weighting values based on the statistical values by different weighting formulas, multiplying each weighting value with the original statistical values corresponding to the various size of windows, summing up to obtain an ultrasound structure scatterer value of the nth ultrasonic signal point, and generating an ultrasound scatterer structure image based on a matrix of the ultrasound scatterer values. The present invention further combined interpolation method can reduce the computation time and retain the 80% accuracy.

The invention provides a phased array ultrasonic evaluation method of crystal grain size, the method includes: using the primary bottom echo and the secondary bottom echo to obtain the experimental longitudinal wave scattering attenuation coefficient; deriving the linear phased array from the Huygens principle The probe radiates the sound field, receives the average sound pressure through the probe, defines the diffraction correction coefficient of the linear phased array probe and calculates the final diffraction correction coefficient; according to the Weaver ultrasonic scattering model, the theoretical relationship between the grain size and the longitudinal wave scattering attenuation coefficient is obtained, based on the nonlinear minimum The square method uses polynomial fitting to obtain the proxy model of the grain size and the theoretical longitudinal wave scattering attenuation coefficient; the experimental longitudinal wave scattering attenuation after removing the diffraction loss is substituted into the proxy model to invert the grain size value. The invention eliminates diffraction loss interference, fuses multi-angle sound beam information, and greatly reduces relative error compared with traditional methods, and provides a feasible and reliable means for estimating the grain size of polycrystalline materials.

The invention relates to an ultrasonic scattering coefficient optimal computation method for crack direction recognition, belonging to the field of nondestructive examination. According to the method, an ultrasonic phased array detection system is used for acquiring full-matrix data of a crack defect; firstly, the acquired data are used for performing full-focusing imaging on the defect to determine the position of the defect and then a scattering coefficient space distribution of the crack defect is computed to determine an angle of the crack; the quantity of wafers included in a sub array and the quantity of wafers between adjacent sub arrays greatly affect the measurement precision of the crack angle. A plurality of evaluation indexes are used for evaluating the quantity of a crack angle measurement result according to the quantities of the wafers included in different sub arrays and the wafers between the adjacent sub arrays, and the measurement result is comprehensively evaluated by a main component analysis method to obtain an optimal measurement result; corresponding parameters, namely the quantities of the wafers included in the sub arrays and the quantity of the wafers between the adjacent sub arrays, are optimal detection parameters.

Realistic ultrasound imaging simulation requires modeling of scatterers corresponding to different imaging speckle appearances. A scatterer generator acquires a plurality of ultrasound signal samples,each corresponding to a different ultrasound capture and reconstructs a scatterer representation from the ultrasound signal samples and associated Point Spread Functions. Point Spread Functions (PSFs) may be estimated from multiple image acquisitions at the same reference position resulting from beam-steering. Reconstructed scatterers may then directly be used in ultrasound simulation or an additional step of modeling the scatterers may be applied. Statistical distribution parametrization or texture synthesis may be used to model the scatterers. Different scatterer models may be used for different homogeneous regions. The reconstructed scatterers and / or the scatterer models may be registered into a library of scatterers by the scatterer generator.