Abstract: Quadrature demodulation apparatus and method for detecting a contrast agent in an ultrasonic echographic system, including an in phase/quadrature demodulator for determining the resolved complex real and imaginary in phase and quadrature components of return signals and a contrast agent detector determining the complex difference between first and second return signals. The detector is implemented as a magnitude of difference detector determining the magnitude of the complex difference of pairs of first and second return signals wherein the real and imaginary components of the return signals, including magnitude and phase information, are used to determine the magnitude of the complex difference between first and second return signals.

Abstract: An ultrasound system that utilized a transducer assembly having elements distributed in two dimensions in conjunction with a beamformer that, for each beam to be formed, samples the output of each utilized element based on a preset delay value selected for each element utilized to form the beam to form a c-scan like set of data.

Abstract: A magnetic resonance imaging apparatus is provided with a gradient coil system for generating a magnetic gradient field in an imaging volume of the apparatus, the gradient coil system being arranged in a space providing isolation by means of vacuum, and also with an RF coil for generating an alternating RF magnetic field in the imaging volume, wherein the RF coil surrounds the imaging volume. An RF shield for concentrating the power generated by the RF field in the RF frequency coil substantially in the imaging volume is located in the vacuum isolated space between the gradient coil system and the RF coil.

Abstract: The method of the invention controls an ultrasound system to image a microbubble contrast agent in a region of fluid flow and/or a region of tissue that is perfused by blood or other fluid. A transducer transmits ultrasound acoustic signals having a fundamental frequency f and receives echoes resulting from interaction of the ultrasound signals with both tissue and the microbubble contrast agent. A transmitter controls the transducer to transmit ultrasound signals at a sufficient power level to destroy the microbubble contrast agent. A receiver processes the echoes and selectively extracts signal components that exhibit a noninteger multiple of the fundamental frequency f of the transmitted acoustic signal. The system then produces images, principally from signal components including those that exhibit the noninteger multiple of the fundamental frequency f.

Abstract: A Doppler receiver has a wide dynamic range and operates in a differential mode.

Abstract: Variable multi-dimensional apodization control for an ultrasonic transducer array is disclosed. The variable multi-dimensional apodization control is applicable to both piezoelectric based transducers and to MUT based transducers and allows control of the apodization profile of an ultrasonic transducer array having elements arranged in more than one dimension.

Abstract: An ultrasound system for continuous imaging and for controlling release of an encapsulated agent from a carrier comprises a housing secured to a patient's body, a transducer mounted within the housing, means for controlling the transducer to insonify the drug carrier with an ultrasonic signal and to thereby cause the release of the agent, and means for processing an ultrasonic echo signal to produce an image. Also, a method for controlling release of an encapsulated agent from a carrier comprises the steps of measuring a physiological parameter of a patient based on an ultrasonic echo signal, comparing the physiological parameter to a threshold, and transmitting an ultrasonic signal to insonify the carrier and thereby cause the release of the agent from the carrier in accord with the measured physiological parameter.

Abstract: A data field assigns data values to positions in a multi-dimensional space. The data values on the iso-surface are equal to a predetermined iso-value. The method of the invention is carried out on a sampled data field. The sampled data field assigns sampled data values to lattice positions on a multidimensional lattice in conformity with a sampling of the data field. A method of deriving an iso-surface in a multi-dimensional data field comprises the following steps. A binary shell is derived from the sampled data field. The binary shell comprises cells in the multi-dimensional lattice. Each cell of the binary shell includes lattice positions having a sampled data value larger than the iso-value as well as lattice positions having a sampled data value smaller than the iso-value. A line of sight is chosen in the multi-dimensional space and cells in the binary shell which are intersected by the line of sight are determined.

Abstract: The invention relates to an MR imaging method which is notably suitable for applications where an as short as possible acquisition time is desired. The method is based on the SENSE method which enables the image acquisition to be performed with a reduced FOV (field of view); parallel, multi-channel detection is then performed by means of receiving elements having different spatial sensitivity profiles. The invention is based on the recognition of the fact that conventional birdcage resonators can be tuned to different resonance modes whose spatial sensitivity profiles deviate strongly. A birdcage resonator that is composed of a plurality of sub-resonators can operate simultaneously in different resonance modes at one resonance frequency and enables parallel, independent signal detection with different sensitivity profiles; according to the invention this feature is used to carry out the SENSE method.

Abstract: The invention relates to a stabilization device for stabilizing parts of a body during imaging diagnostics performed by means of magnetic resonance, for example computed tomography. The stabilization device includes a flexible RF coil (6) which is pressed against the part of the body to be examined by way of a supporting element (1). The stabilization device in accordance with the invention is distinct from customary stabilization devices that must be applied by a third party and often have to be fixed by means of belts in that the supporting element (1) is constructed so as to be adapted to the part of the body to be stabilized and also so as to be elastically compliant, and that the coil (6) is connected to the supporting element (1) in such a manner that it follows the elastic deformation thereof and hence is self-adapting.

Abstract: A magnetic resonance imaging method employs sub-sampled signal acquisition from a number of receiver coils such as surface coils. A full field-of-view magnetic resonance image is reconstructed on the basis of the sensitivity profiles of the receiver coils, for example on the basis of the SENSE technique. The reconstruction is carried out mathematically as an optimization, for example, requiring a minimum noise level in the magnetic resonance image. According to the invention, a priori information is also involved in the reconstruction and the a priori information is taken into account especially as a constraint in optimization.

Abstract: The transfer of vibrations that generate noise should be avoided in medical MRI apparatus. In accordance with the invention the gradient coil system 40 is suspended by means of suspension elements 48 whose transverse stiffness is much smaller than their axial stiffness. Such suspension elements should be attached to the coil carrier 40 at a vibration-free point, that is, a point that does not exhibit vibrations in all three co-ordinate directions. The longitudinal direction of the suspension element 48 should coincide with the vibration-free direction. Preferably, the suspension element is provided with an active drivable element 37 (a piezo element) for virtually reducing the stiffness of the suspension element in the axial direction, thus compensating also for residual vibrations that could still be present in the vibration-free direction.

Abstract: The invention relates to a method of and a device for cleaning a slip ring which is rotatable about an axis of rotation, is supported by a frame and a circumferential surface of which is provided with a signal or power track which extends so as to be concentric with the axis of rotation. A chamois cloth drenched in a liquid is pressed against the circumferential surface provided with the track and the slip ring is rotated while the chamois cloth is kept pressed against the circumferential surface. The device includes a support which is to be connected to the frame supporting the slip ring and in relation to which the chamois cloth can be fixed. The support includes a pressure strip for pressing the chamois cloth against the circumferential surface of the slip ring provided with a track.

Abstract: The invention relates to an array of ultrasound transducers which each comprise a substrate (1), a membrane (2), a first electrode (4), a piezoelectric layer (5), and a second electrode (6), wherein the substrate (1) comprises at least one opening (3) which adjoins the membrane (2) at one side, while the piezoelectric layer (5) has a high piezoelectric coupling coefficient k and is textured. The invention further relates to an ultrasound transducer and to a method of manufacturing an array of ultrasound transducers.

Abstract: The invention implements a method for adaptively using raw image data (before compression) to produce pixel display values in an ultrasound system in accord with variations in signal-to-noise ratio. Initially, for each subject pixel of an image, a first regional value is derived by taking into account values of a neighborhood of pixels that includes the subject pixel. The first regional value is then compared to a threshold value related to noise and each subject pixel is assigned a classification as a tentative signal pixel if the regional value equals or exceeds the threshold value. Any pixel value not so classified is considered a tentative noise pixel. A second regional value is then derived for each subject pixel by taking into account first regional classifications of a second neighborhood of pixels that includes the subject pixel. If the number of signals classified as signal in the second neighborhood is less than a second threshold, the subject pixel is classified as noise.

Abstract: The invention relates to a method of and a device for exciting the nuclear magnetization in a limited volume of an object to be examined, utilizing a microcoil (L) which is present in the volume and is attached, for example, to an interventional instrument during the formation of a magnetic resonance image of the object to be examined. The excitation of the nuclear magnetization is performed by at least one RF pulse whose frequency spectrum does not overlap the range of the spin resonance spectrum, so that no nuclear magnetization is excited outside the close range of the microcoil in the object to be examined. The microcoil, however, is provided with an active or passive circuit (for example, it is wired together with at least one capacitance (C) and a non-linear component (D1, D2) so as to form a non-linear resonant circuit) which locally generates an RF signal from the RF pulse.

Abstract: An ultrasonic image processing method includes acquiring ultrasonic signals related to an object having moving parts in a medium; constructing an ultrasonic grayscale 2-D image sequence representing a cross-section of a segment of the object with respect to a longitudinal axis (X) perpendicular to the grayscale image lines (Z); estimating the displacements and the displacement gradients of a boundary of the object; and normalizing the gray levels in a boundary zone and color-coding the points of the boundary zone of an image sequence as a function of the displacement gradient values, in order to provide color-coded information of the object moving parts displacement variations. An ultrasonic examination imaging system for carrying out the method having a color display system is also disclosed.

Abstract: A method of and system for programming one or more personalized settings of a user for adjustable components of a vehicle, by using a communication device capable of communicating data to the vehicle. It includes providing the user with a radio frequency identification (RFID) tag. The RFID tag includes machine-readable information regarding personalized settings of the user for at least one adjustable component of the vehicle. The information from the RFID tag includes the identity of the user. First, information is read from the RFID tag using an RFID reader when the RFID tag is operationally proximate the RFID reader. Next, a profile database is queried to access a personal profile of the user based upon the identity of the user as read from the RFID tag. The personal profile includes personalized settings for each component of the vehicle to be set.

Abstract: An ultrasound system that has transmit and receive circuitry that, pursuant to a plurality of image settings, transmits ultrasound signals into a patient, receives echoes from a patient and outputs a signal representative of the echo. Control circuitry is provided that sequentially adjusts the image settings so as to cause the transmit and receive circuitry to have a sequence of imaging configurations during an ultrasound imaging study. A memory may be provided that stores a plurality of state diagrams, each defining a sequence of imaging configurations for a particular imaging study, which are accessible by the control circuitry, wherein the control circuitry accesses a selected state diagram to conduct an imaging study. Such a system is particularly useful for imaging studies that utilize contrast agents.

Abstract: A diagnostic imaging system, notably a magnetic resonance imaging system comprises a receiver antenna for picking-up magnetic resonance signals and an ultrasound probe for receiving ultrasound echoes. A reconstruction unit is arranged to reconstruct a diagnostic image from the magnetic resonance signals and the ultrasound echoes in particular, the magnetic resonance image and ultrasound images are registered in a common reference frame and geometric distortions in the ultrasound image are corrected on the basis of the magnetic resonance image. Different tissues types are distinguished in the magnetic resonance image and corrections are made for differences between ultrasound sound velocities in these tissue types. Further, information contained in the magnetic resonance signals can be displayed in combination in the ultrasound echoes.