Abstract: Disclosed is a magnetic resonance method for the quantification of molecular diffusion. The method uses a diffusion-weighted (dw) double echo steady state sequence (DESS). In particular, the method allows direct quantification of molecular diffusion from two steady state scans with differing diffusion weighting such as one with diffusion-weighting and preferably one without diffusion weighting. Such a quantification of molecular diffusion allows for rapid and/or quantitative measurements of physiological and/or functional parameters of living tissue. Quantitative measurements are often a prerequisite for pre-clinical and clinical research as well as for clinical trials in drug research performed at different sites. Especially for the early diagnosis of subtle or diffuse pathological changes, quantitative MR promises to have a very significant impact.

Abstract: In a magnetic resonance apparatus and method to generate an image data set by means of a radial scanning of a raw data set, at least one calibration measurement is implemented for at least one predetermined spoke of the radial scan, and a gradient moment difference between an assumed gradient moment and an actually applied gradient moment is determined along the at least one predetermined spoke. Readout of all spokes of the predetermined raw data set ensues by activating multiple magnetic field gradients in spatial directions in order to respectively read out scan points of a respective spoke. The position of each scan point of each spoke is corrected depending on the gradient moment difference, by the position of the respective scan point that is assumed based on the respective activated magnetic field gradients being shifted by the gradient moment difference.

Abstract: In a magnetic resonance tomography local coil arrangement and a method for processing signals received thereby, at least one local coil is fashioned to receive at least one reception signal and at least one amplifier is provided that amplifies the at least one reception signal. A frequency converter generates at least one intermediate frequency signal from the at least one reception signal the intermediate frequency of the intermediate frequency signal differing from the reception signal frequency of each reception signal. An analog-digital converter converts the analog intermediate frequency signal into a digitized signal. A shielding device shields against at least radio-frequency signals, the shielding device surrounding at least the analog-digital converter. At least one frequency filter is arranged between the at least one local coil and the analog-digital converter, the frequency filter exhibiting a transmission range for signals with the intermediate frequency of an intermediate frequency signal.

Abstract: The present invention discloses a modular MRI imaging system. The imaging system includes MRI radio-frequency antenna arrays separate from the patient support structure. The antenna arrays are affixed to a thin, flexible film such that they may be located next to the anatomical region of interest. In addition, multiple antenna arrays may be configured in various planar or three-dimensional arrangements to optimize the FOV and SNR. Separate patient support structures are provided that enhance ergonomics and patient stabilization. By removing the antenna from the housing, the support structures may be designed without the constraints of supporting the antenna or the associated electronics. The MRI imaging system further employs a preamplifier module. The preamplifier module houses the preamplifier and much of the other associated circuitry for each of the antennae. The preamplifier module operates to combine the signals from the antenna arrays and pass the signals to the MRI system.

Abstract: The invention relates to a sensor for measuring structures in a surface, e.g. a fingerprint sensor comprising a chosen number of sensor elements at chosen positions for coupling to a finger surface having a size less or comparable to the size of the structures in the finger surface, and a processing unit including interrogation electrodes coupled to said sensor elements for providing impedance measurements at said finger surface, the processing unit being mounted on one side of a substrate and the sensor elements being positioned on the opposite side of said substrate, the substrate including through going first conducting leads between said sensor elements and said interrogation electrodes. The substrate is made from a semiconductor material such as silicon and said first conducting leads are constituted by through going substrate sections of a chosen size surrounded by an insulating dielectric separating them from the substrate.

Abstract: In a method and apparatus to reduce distortions in diffusion imaging, at least one first measurement is implemented with a first diffusion weighting for a number of slices that are spatially separated from one another and at least one second measurement is implemented with a second diffusion weighting for the number of slices that are spatially separated from one another. A deskewing function is determined as are correction parameters to deskew diffusion-weighted magnetic resonance images on the basis of the measurements, so that image information and/or correction parameters of different slices are linked with one another. The diffusion-weighted magnetic resonance images are distortion-corrected on the basis of the deskewing function and the correction parameters.

Abstract: The phase background of a proton resonance frequency shift treatment image may be estimated by fitting a combination of baseline images to the treatment image.

Abstract: A method for magnetic resonance imaging, in which a magnetic resonance imaging device employs a multi-echo imaging sequence, includes the steps of: applying, to one of the multiple echoes, a first number of steps of phase encoding, applying a readout gradient, and collecting the data of this echo to reconstruct an anatomical image; and applying, to another one of the multiple echoes, a second number of steps of phase encoding, applying a readout gradient, and collecting the data of this echo to construct a temperature image. The method is capable of obtaining at the same time both a temperature image with high time resolution and an anatomical image with high spatial resolution.

Abstract: According to one embodiment, a magnetic resonance imaging apparatus is provided. A first imaging unit captures a plurality of first image data including first and second reference frames. The frames include a reference position and a target region in an object. A movement amount calculation unit calculates a movement amount of a local position between the first and second reference frames. A correction parameter setting unit sets a first correction parameter for correcting body motion of the object, based on the movement amount. An error map generating unit generates a predictive error map including a pixel value corresponding to a predictive correction error. The predictive correction error is obtained from a predictive position based on the movement amount and a predictive correction position based on the first correction parameter. A display unit displays the predictive error map and the first image data.

Abstract: In a method and a device for specific absorption rate monitoring in a magnetic resonance system wherein multiple transmit coils are independently charged with respective currents, a primary model point voxel and at least one auxiliary model point voxel are automatically selected from among multiple voxels that model a modeled examination subject. The primary model point voxel is that voxel in which an absolute maximum of a total field variable occurs that is produced by the respective electrical fields emitted by the transmit coils. The at least one auxiliary model point voxel is that voxel in which a relative maximum of the variable occurs.

Abstract: The present invention relates to a method and system for polarizing a solid compound of interest via spin transfer from an optically-pumped alkali vapor. In one embodiment, the method provides a cell which contains a solid compound as well as pure alkali metal and some amount of buffer gas. The cell is heated to vaporize some of the pure alkali. Resonant laser light is passed through the cell to polarize the atomic vapor, a process known as “optical pumping.” Optical pumping can transfer order from photons to atoms, causing a buildup of vapor atoms in one angular momentum state. This vapor polarization is then transferred through the surface of the solid compound in order to polarize the nuclei in the bulk of the compound. This can produce nuclear polarizations in the sample many times larger than the limit set by thermal equilibrium. The method can be used in nuclear magnetic resonance (NMR) or magnetic resonance imaging (MRI).

Abstract: A multicoil NMR detection and imaging apparatus allows multicoil NMR detection and imaging to be performed efficiently at low operating frequencies. The apparatus comprises an AC voltage generator, a transmit switching circuit, a coil switching network, an array of two or more detection coils, a set of receive switching circuits with one switching circuit for each detection coil, and a set of preamplifier circuits with input impedance substantially greater than the impedance of each respective detection coil at the intended operating frequency. The AC generator produces an alternating current waveform that is routed through one of more detection coils during transmit mode while the preamplifier circuits are isolated from the detection coil(s). During receive mode the AC generator is isolated from the detection coils to prevent noise from the transmitter from degrading the quality of received signals.

Abstract: A transmit-receive switching circuit is offered which is for use in an NMR spectrometer that employs a solid-state NMR probe using a cooled detection coil. The switching circuit is cryogenically cooled to reduce thermal noise in use. The switching circuit has a first terminal for applying high-power RF pulses sent in from the power amplifier of the NMR spectrometer, a second terminal for sending the RF pulses applied from the first terminal to the NMR detector via crossed-diodes and for receiving and entering a low-power NMR signal detected by the NMR detector, and a third terminal for sending the NMR signal entered from the second terminal toward a preamplifier. Plural stages of shunts are connected to the transmission line connecting the second and third terminals such that one stage of shunt corresponds to a 90° phase shift in the RF radiation.

Abstract: A magnetic resonance imaging apparatus includes an imaging condition setting unit and an image data acquisition unit. The imaging condition setting unit sets an imaging condition applying first and second suppression pulses of which at least ones of types, center frequencies and frequency bands are different from each other. The first and the second suppression pulses frequency-selectively suppress at least one of fat and silicone. The image data acquisition unit acquires image data according to the imaging condition.

Abstract: In a method and an apparatus for magnetic resonance guided high intensity focused ultrasound (HIFU), precise localization of the focal point of the HIFU is determined by imaging an examination subject in parallel with GRE sequences that respectively include a positive monopolar gradient pulse and a negative monopolar gradient pulse, that respectively encode the acoustic radiation force (ARF)-induced phase shift that is induced by the simultaneous activation of HIFU during the sequences. A GRE phase image is reconstructed from each acquisition sequence, and a difference image is formed between the two GRE phase images, from which the HIFU focal point is determined. An average image is formed of the two GRE phase images from which PRFS temperature map is determined simultaneously to ARFI map.

Abstract: An electromagnetic interference suppression device and an MRI apparatus using such a device are disclosed. The MRI apparatus may include a main magnet, a gradient coil, an RF coil placed in a shielding chamber, a control system, and an electromagnetic interference suppression device.

Abstract: The present invention discloses a method and apparatus for brain perfusion magnetic resonance imaging (MRI) technique with the removal of cerebrospinal fluid (CSF) pixels. This invention utilizes a CSF/brain-contrast-enhanced image, wherein the CSF/brain-contrast-enhanced image is defined as the signal difference between CSF and brain matter divided by a standard deviation of air background random noise is larger than 3, acquired from the subject's brain, and applies a segmentation technique to remove the CSF pixels. After removing the CSF pixels on parametric images, the extent of brain tissue with delayed perfusion can be better identified. By using a good region of interest enclosing the correct delayed-perfusion region, the measurement on the tissue volume and perfusion parameters would be more accurate than the area contaminated by CSF pixels.

Abstract: It has an object to suppress reduction of an examination efficiency caused by limitation of SAR (specific absorption rate) to the minimum level in an examination that plural imaging sequences containing different imaging sequences are consecutively executed. In consideration of the time variation of time average SAR value in the overall examination, the order of executing the imaging sequences is determined so that the SAR value falls within a predetermined range and the waiting time between imaging sequences is minimum. The determination is performed by calculating a waiting time of each of all conceivable execution orders and selecting an execution order having the minimum waiting time.

Abstract: A nuclear magnetic resonance well logging tool, where some embodiments comprise two, oppositely oriented magnets separated by a pole piece to guide static magnetic flux into a sensitive volume, and another pole piece serving as a core for several antennas. For some embodiments, the antennas are solenoids. Two of the antennas serve as transmit and receive antennas, where they are driven to generate an elliptically polarized magnetic field, and their antenna responses are combined so that the combined response is sensitive to elliptically polarized magnetic fields, but with zero gradient in the z-direction. A third antenna serves as a receive antenna sensitive to magnetic field vectors having a sinusoidal spatial variation in the z-direction of period equal to the length of the third antenna. A fourth antenna serves as a receive antenna sensitive to sinusoidal magnetic field vectors with the same spatial-frequency as the third antenna, but phase shifted by 90 degrees.

Abstract: A radio frequency coil assembly includes an annular conductor (20, 22, 120) configured to support a sinusoidal electrical current distribution at a magnetic resonance frequency, and a radio frequency shield (30, 32, 34, 52, 60, 61, 130) shielding the annular conductor in at least one direction, the radio frequency shield including at least one of (i) a cylindrical shield portion (30, 60, 61, 130) surrounding a perimeter of the annular conductor, and (ii) a planar shield portion (32, 34, 52) arranged generally parallel with the annular conductor. In a magnetic resonance scanner embodiment, a magnet (10) generates a static magnetic field (B0), a magnetic field gradient system (14) is configured to superimpose selected magnetic field gradients on the static magnetic field, and said radio frequency coil assembly is arranged with the annular conductor generally transverse to the static magnetic field (B0).