144 results about "Radiation force" patented technology

A remote palpation technique in breast imaging involves the use of multiple applications of radiation force in rapid succession throughout a two-dimensional plane in the target tissue medium (10), and combination of the small, two-dimensional displacement maps from each force location into a single, larger remote palpation image (block 43). Apparatus for carrying out the foregoing method is also disclosed.

A method for determining a shear elasticity and shear viscosity of a material based on resonance characteristics. A focused ultrasound wave is directed at the material to induce oscillations in the material, and a velocity of the material is measured. A spectrum of frequency of oscillation versus velocity is developed, and the resonance characteristics exhibited by the spectrum are used to estimate the shear elasticity and viscosity of the material.

Methods for determining the shear modulus of a tissue of an individual are disclosed. In one embodiment, an acoustic pulse is transmitted and a reference echo signal is received. A first push pulse is transmitted at a second location of the individual. A second push pulse is transmitted at a third location of the individual. A series of tracking pulses are transmitted at the first location and a tracking echo signal is received from each tracking pulse. The effect of the first and second push pulses on the tissue is determined through analysis of the tracking echo signals. The shear modulus of the tissue is calculated based on the effect of the push pulses on the tissue. A system for imaging a region of tissue is presented.

A system and method for imaging the localized viscoelastic properties of tissue is disclosed. An oscillatory radiation force is applied to tissue in order to induce a localized oscillatory motion of the tissue. The phase and amplitude of the induced localized oscillatory motion of the tissue is also detected while the oscillatory radiation force is being applied. The viscous properties of the tissue are determined by a calculation of a phase shift between the applied oscillatory radiation force and the induced localized oscillatory motion of the tissue. The oscillatory force force inducing local oscillatory motion may be a single amplitude modulated ultrasound beam.

Ultrasound methods and apparatus for mixing two or more different liquids are disclosed. The ultrasound methods and apparatus may mix varied components including drugs, polymers, and coatings for application to a variety of medical apparatus surfaces. The apparatus and technique can generate a proper mixture which is uninterruptedly/continuously delivered to the surface of the medical apparatus. The apparatus may include specific ultrasound transducer/tip configurations which may allow for the mixing of different liquids in a mixing camera located inside of the vibrating tip. The apparatus and methods of the present invention may mix different drugs, applying them to stent surface using different effects like ultrasound cavitation and radiation forces. Furthermore, the disclosed methods and apparatus may generate a mixture and may deliver a targeted, gentle, highly controllable dispensation of continuous liquid spray which can reduce the loss of expensive pharmaceuticals.

The invention provides for medical instrument (200, 400) comprising a magnetic resonance imaging system (202) and a high intensity focused ultrasound system (222). A processor (246) controls the medical instrument. Instructions cause the processor to control (100) the magnetic resonance imaging system to acquire the magnetic resonance data using a pulse sequence (254). The pulse sequence comprises an acoustic radiation force imaging pulse sequence (500, 600). The acoustic radiation force imaging pulse sequence comprises an excitation pulse (512) and a multi-dimensional gradient pulse (514) applied during the radio frequency excitation pulse for selectively exciting a region of interest (239) encompassing a target zone and at least a portion of the beam axis. The instructions cause the processor to control (102) the high intensity focused ultrasound system to sonicate the target zone during the acoustic radiation force imaging pulse sequence and reconstruct (104) a radiation force image (258) using the magnetic resonance data.

This invention relates to diagnostic and screening medical ultrasound in general and to ultrasound-stimulated detection and location, Image-based Dynamic Ultrasound Spectrography, Acoustic Radiation Force Imaging, and similar modalities in particular. In this invention, an ultrasound signal is emitted into tissue and the resulting radiation force induces localized lower frequency oscillations, which are then received by various acoustic sensors and analyzed to determine certain features or characteristics of the interrogated region. The sensors can be arranged in the form of a ring, in any random arrangements, or positioned in specifically chosen locations. An ultrasonic imaging and excitation transducer generates certain stimulating signals which are received by the breast tissues and which, if they contact a microcalcification, other target, or any region with sharply different mechanical and visco-elastic properties, will result in reflected, demodulated, or re-radiated signals. These signals will propagate away from the targets and detected by the various receiving sensors.

System and method for determining viscoelasticity of curved tissue walls using ultrasound bladder vibrometry (UBV). The UBV is a non-invasive technique utilizing, in a specific case, a focused ultrasound radiation force to excite Lamb waves in a curved bladder wall and pulse-echo techniques to track the tissue deformation propagating through such curved wall. Cross-spectral analysis is used to calculate the wave velocity, which is directly related to the elastic properties of the bladder wall.

The invention relates to a biological tissue multi-characteristic imaging method based on the acoustoelectric effect and acoustic radiation force. The method comprises the steps that the size of the focal spot of each focusing domain of an ultrasonic transducer under a focusing ultrasonic disturbance mode is measured, and the sequence that the focusing domains are scanned by focusing ultrasonic waves is determined; a low-intensity tracking pulse is emitted to the ultrasonic transducer, and under the condition that ultrasonic focusing is ignored, a boundary measurement voltage vector phi and anecho signal of the tracking pulse are obtained; when an excitation current reaches the wave peak or the wave trough moment, a high-intensity excitation pulse is emitted to the ultrasonic transducer,so that an emission and scanning mechanism of the ultrasonic transducer works in a focused ultrasonic disturbance mode, and the focusing ultrasonic waves disturb the nth focusing domain; during focusing ultrasonic disturbance, the boundary measurement voltage vector phi n obtained after disturbance is measured, a low-intensity tracking pulse is emitted to the ultrasonic transducer again, and an echo signal is received; an acoustoelectric signal and corresponding displacement information of the nth focusing domain are obtained; the obtained data is processed, and a biological tissue image is reconstructed.

An apparatus and method of using an optical coherence elastography (OCE) under acoustic radiation force (ARF) excitation includes the steps of inducing an excitation wave in a blood sample by use of an ultrasound beam from an ultrasonic transducer; measuring an elastic property of the blood sample by use of an optical coherence tomography (OCT) beam transverse to the ultrasound beam to dynamically measure the elastic property of the blood sample during coagulation and assessing the clot formation/dissolution kinetics and strength.

A three-dimensional temperature reconstruction combination method based on a flame light field refocus image is disclosed. The invention relates to the three-dimensional temperature reconstruction combination method based on the flame light field refocusing image. By using an existing nearest neighbor method, the physical reconstruction precision of the outermost layer and secondary outer layer offlames is low, and when a Lucy-Richardson deconvolution method is used in intermediate layer flame physical reconstruction, the precision is low. In the invention, the above problems are solved. Themethod has the following steps of 1, using a light field camera to shoot the flame and record the three-dimensional light field image of the flame; 2, acquiring the light field refocusing image of theflame; 3, acquiring the point spread function of the light field camera; 4, acquiring a flame chromatography image; and 5, acquiring a fitting relationship between a black body plane surface radiation force and a gray scale, and reconstructing the radiation force for the gray scale of the flame chromatography image based on the fitting relationship, and according to the radiation force, acquiringa three-dimensional flame temperature. The method is used for the flame image processing field during a high temperature flame temperature reconstruction process.

A method and instrumentation for ultrasound mediated delivery of drugs to diseased tissue use ultrasound beams with frequency and focusing that provides an ultrasound radiation force acting on the drug and surrounding fluid, which produces a convection of drugs and compensates for the lack of a pressure gradient. To manipulate drug encapsulations and also stimulate transport of drugs across biological membranes, like the cell membrane or the blood brain barrier, the method and instrumentation use low frequency beams with high mechanical index. The method and instrumentation additionally uses ultrasound heating of the tissue to increase blood flow and manipulate thermally sensitive particles.

Methods for generating a customized spectral profile, which can be used to generate a corresponding filter, lamp or other type of illuminant. A trial spectrum is generated. A reference spectrum is determined or otherwise obtained. A SOURCE spectrum is determined or otherwise obtained. One or more optical indices are calculated using the trial spectrum and one or more of the optical indices are optimized by varying the trial spectrum to generate the customized spectral profile. A radiation force parameter can be used to minimize unsafe build-up of light in spectral regions. Adaptations of color rendering parameters can be used in the optimization process. Smoothing parameters can be used to enable easier design of filter structures. A reflectance camera can be used to measure reflectance data at one or more pixels of a digital representation of an object to be illuminated.

The present invention relates to a laser micro-control device and method for the transportation and directional movement of particles and cells. In the device, a light source system and a two-dimensional moving loading platform are arranged in the same plane. The light source system is a laser, a light beam converting system and a focusing system which are orderly placed. The laser, the light beam converting system and the focusing system are arranged on the same optical axis. The present invention utilizes the characteristic that laser beam has gradient force and radiation force to restrict particles and cells needing transportation and directional movement in a light beam focusing area, and can carry out the transportation of particles and cells through a single laser beam as well as the directional movement of particles and cells through two intersecting laser beams, so as to realize the method of controlling particles and cells. The present invention can utilize laser micro-control technology to realize the direct transportation and directional movement of particles and cells, and can be applied to micro-fluidic chemistry or biological analysis systems.

A flame temperature field rebuilding method based on physical parameter consistency comprises the following steps of a, synchronously shooting an image sequence of a combustion flame from a plurality of angles of view and voxelizing the flame through a visual hull technology; b, calibrating a response curve of a camera; c, initiating a flame refractive index field and computing an initial radiation force field of the flame according to an imaging model of the flame; d, computing the radiation force field and the refractive index field in an iterative mode until the radiation force field and the refractive index field meet physical consistency in numerical value; e, computing a final flame temperature field according to a lookup table between a radiation force and a temperature. The flame temperature field rebuilding method based on the physical parameter consistency is based on the fact of the consistency of the two physical parameters of the flame radiation force field and the refractive index field, an algorithm for computing the flame temperature field in an iterative is provided, and the flame temperature field rebuilding method fully takes refraction on light rays due to uneven distribution of the flame refractive index field into consideration, so that the accuracy of temperature rebuilding is greatly improved. The flame temperature field rebuilding method based on the physical parameter consistency can be applied to field of commercial measurement, thermal power plant monitoring, virtual reality and the like.

The invention discloses an ultrasonic peeping probe and an elastic imaging system and method. The ultrasonic peeping probe comprises an ultrasonic transducer array including multiple ultrasonic transducers for transmitting ultrasonic waves and receiving ultrasonic echoes, reflected by the biological tissue to be detected of ultrasonic waves, and a self-focused ultrasonic transducer for producing focused ultrasonic wave beams, wherein the focused ultrasonic wave beams produce an acoustic radiation force acting on the biological tissue to be detected. The ultrasonic peeping probe produces the focused ultrasonic wave beams through the self-focused ultrasonic transducer, acts on the biological tissue to be detected through the acoustic radiation force of the focused ultrasonic wave beams and accordingly makes the biological tissue to be detected deform. Accordingly, the ultrasonic echo signals of the biological tissue before and after compression are obtained by adopting the ultrasonic peeping probe without the external force exerted by an operator, the operating process is simple and convenient without external mechanical devices, and the system cost is reduced.

The invention discloses a cell adhesion force measuring instrument and measuring method based on acoustic surface waves. The cell adhesion force measuring instrument comprises a lithium niobate crystal plate, a silver interdigitatal electrode annular array, a PDMS (polydimethylsiloxane) micro-channel and a micro-vision servo system, the micro-vision servo system comprises an upper computer system based on a PXI (peripheral component interconnect) bus, a multi-path signal generating system and a micro-vision monitoring system, the silver interdigitatal electrode annular array is arranged on the upper periphery of the lithium niobate crystal plate, the lithium niobate crystal plate and the silver interdigitatal electrode annular array form an interdigital transducer, and the silver interdigitatal electrode annular array is connected with the multi-path signal generating system. According to the measuring instrument, an expected sound field is synthesized in a PDMS micro-channel cavity by the aid of the interdigital transducer and the micro-vision servo system, cells are operated by the aid of radiation force of the acoustic surface waves, cell adhesion force is measured, and the measuring instrument has the advantages of simplicity and easiness in operation, fewer interference factors and the like.

The invention discloses an acoustic tweezers device. The acoustic tweezers device comprises an ultrasonic emitting mechanism, and a waveguide structure arranged on the ultrasonic emitting mechanism; the ultrasonic emitting mechanism is used for emitting ultrasonic waves; and the waveguide structure is used for conducting the ultrasonic waves. The acoustic tweezers device further comprises a resonant unit body arranged on the waveguide structure; the ultrasonic waves excite the resonant unit body for resonance; and a local area field for capturing particles is generated on the surface of the resonant unit body. The used ultrasonic frequency is lower, and the precise phase modulation is not needed, so that a transducer is easily machined and manufactured, and no complicated electronic systemis needed; a low-frequency sound field emitting mode is modulated only through the designed resonant unit body; and the local area field is generated on the surface of the resonant unit body to realize such operations as capturing of micron-scale particles. When the ultrasonic emitting mechanism is turned off, due to loss of the sound radiation force, the captured particles on the surface of theresonant unit body can be released. The acoustic tweezers device is simple in manufacturing process and low in cost, and can achieve mass production.