Abstract: An ultra-low magnetic field NMR system can non-invasively examine containers. Database matching techniques can then identify hazardous materials within the containers. Ultra-low field NMR systems are ideal for this purpose because they do not require large powerful magnets and because they can examine materials enclosed in conductive shells such as lead shells. The NMR examination technique can be combined with ultra-low field NMR imaging, where an NMR image is obtained and analyzed to identify target volumes. Spatial sensitivity encoding can also be used to identify target volumes. After the target volumes are identified the NMR measurement technique can be used to identify their contents.

Abstract: A method for determining a wax appearance temperature of a fluid includes obtaining nuclear magnetic resonance (NMR) measurements of the fluid at a plurality of temperatures; deriving a NMR parameter from each of the NMR measurements; and determining the wax appearance temperature by analyzing the NMR parameter as a function of temperature. An apparatus for detecting wax appearance in a fluid includes a sample cell for holding a fluid for nuclear magnetic resonance (NMR) measurements at a plurality of temperatures; a temperature measuring device disposed proximate the sample cell; a magnet for polarizing molecules in the fluid in the sample cell; at least one radiofrequency (RF) coil for generating pulses of magnetic field and for detecting NMR signals; and circuitry for controlling and measuring the temperature of the fluid in the sample cell and for obtaining NMR measurements.

Abstract: A system and method for combining parallel imaging and compressed sensing techniques to reconstruct an MR image includes a computer programmed to acquire undersampled MR data for a plurality of k-space locations that is less than an entirety of a k-space grid. The computer is further programmed to synthesize unacquired MR data by way of a parallel imaging technique for a portion of k-space location at which MR data was not acquired and apply a compressed sensing reconstruction technique to generate a reconstructed image from the acquired undersampled MR data and the synthesized unacquired data.

Abstract: A method and apparatus for improving spectral resolution of an NMR measurement in the presence of an inhomogeneous magnetic field. According to one embodiment, a method producing a high resolution nuclear magnetic resonance (NMR) spectrum for a sample in an inhomogeneous magnetic field may comprise generating a first magnetic pulse and a second magnetic pulse, the first and second magnetic pulses being separated in time by a first time period, during the first time period, generating a gradient pulse, repeating the steps of generating the first and second magnetic pulses and generating the gradient pulse N times for different values of a field strength of the gradient pulse, wherein N is an integer greater than one, after each second magnetic pulse, acquiring a signal from the sample, and producing a reconstructed high resolution NMR spectrum from the acquired signals.

Abstract: A radio frequency coil for magnetic resonance imaging or spectroscopy includes a plurality of generally parallel conductive members (70) surrounding a region of interest (14). One or more end members (72, 74) are disposed generally transverse to the plurality of parallel conductive members. A generally cylindrical radio frequency shield (32) surrounds the plurality of generally parallel conductive members. Switchable circuitry (80, 80?) selectably has: (i) a first switched configuration (90, 90?) in which the conductive members are operatively connected with the one or more end members; and (ii) a second switched configuration (92, 92?) in which the conductive members are operatively connected with the radio frequency shield. The radio frequency coil operates in a birdcage resonance mode in the first switched configuration and operates in a TEM resonance mode in the second switched configuration.

Abstract: A method for suppressing the noise component of a measured magnetic resonance (MR) signal is disclosed. In particular, a signal-space projection operator is produced and employed to suppress the noise component from acquired MR signals that is uncorrelated with the spatial pattern of a desired NMR signal. In one embodiment, an fMRI scan is performed to acquire time course image data. The NMR data is filtered with a signal-space projection operator and reconstructed into a series of image frames. In another embodiment, the signal-space projection operator is employed to suppress lipid signal in MRS image data.

Abstract: A manifestation of the invention provides a method for slice selective excitation for magnetic resonance imaging (MRI). A B0 field is applied. A STABLE pulse comprising of a BIR-4 envelope sampled by a plurality of subpulses with a duration is applied, where amplitude and frequency modulation functions of the BIR-4 envelope are slowly varying with respect to the duration of the subpulses. A portion of k-space is read out to obtain k-space data. The STABLE pulse and readout are repeated until sufficient k-space has been acquired. A Fourier Transform of the k-space data is taken.

Abstract: Antenna assemblies for magnetic resonance signals comprise a non-resonant loop antenna and a high impedance differential amplifier. The amplifier can include first and second high electron mobility transistors that have gates coupled to an antenna loop that is defined on a rigid substrate. The non-resonant loop has an effective length of less than about 1/10 of a wavelength of a signal to be detected. Arrays of such loops can be defined on the rigid substrate, and HEMTs for the loops secured to the substrate.

Abstract: A system and method for MR based tracking of a tissue point includes a RF coil assembly configured to emit RF pulse sequences and a system control coupled to the RF coil assembly. The system control is programmed to cause the RF coil assembly to emit a first RF pulse comprising a first pair of two-dimensional (2D) spatially selective beams, each of the beams being directed to a respective tagging location in the subject of interest and wherein the tagging locations are equidistant from a pre-determined point-of-interest. The system control is further programmed to acquire a first series of MR images from a subject of interest, identify the first pair of 2D spatially selective beams in each MR image in the first series of MR images, and track a position of the point-of-interest based on the identified 2D spatially selective beams in the first series of MR images.

Abstract: A radio-frequency transmission arrangement for an MR system for generation of a total B1 field which has a first antenna device that generates a first portion of the total B1 field and at least one antenna insert that generates a second portion of the total B1 field, such that the resulting B1 field is generated by the first antenna device and the at least one antenna insert.

Abstract: A magnetic field adjustment device for a superconducting magnet, wherein magnetic material shim mechanisms are arranged in an axial direction of an inside periphery of the cylindrical superconducting magnet, each of the magnetic material shim mechanisms including a combined shim tray (14 in FIG. 2) in which a plurality of divided shim trays (11 and 12) and shim tray spacers (13) inserted between the divided shim trays are rectilinearly coupled, and magnetic material shims (101) for magnetic field adjustments as are accommodated in the divided shim trays. The magnetic material shim mechanisms afford a high versatility of magnetic material shim arrangements, whereby a correctable range of a magnetic field uniformity can be widened.

Abstract: In a method for deriving information about a selected monosaccharide or polysaccharide such as glucose or glycogen, a selected modification such as saturation is made of magnetic resonance at a magnetic resonance frequency of protons of hydroxyl groups of the selected monosaccharide or polysaccharide. Probative water proton magnetic resonance data are acquired while the selected modification is substantially in effect. Information is derived about concentration or density of the selected monosaccharide or polysaccharide based at least on the probative water proton magnetic resonance data.

Abstract: An apparatus is disclosed for Magnetic Resonance Imaging with specialized imaging coils possessing high Signal-to-Noise-Ratios (SNR). Radio Frequency transmitting and/or Radio Frequency receiving elements include carbon nanotube material, a ballistic electrical conductor having a resistance that does not increase significantly with length. The shapes of the receiving and transmitting elements can be linear, curvilinear, or coiled. The carbon nanotube material can be layered. Due to their enhanced SNR properties, preferred embodiments have smaller static magnetic field strengths with imaging quality comparable to known field systems, leading to substantial reductions in system size and cost. Other preferred embodiments provide enhanced imaging with known MRI static magnetic field strengths.

Abstract: With the objective of eliminating variations in signal strength, there is provided a magnetic resonance imaging apparatus in which the process of 90°-exciting and 180°-exciting spins of two slices intersecting each other respectively and receiving a spin echo generated from an intersection thereof is repeated while the intersection is sequentially parallel-moved to a plurality of lines, thereby to generate, based on the received spin echo, a two-dimensional image at the time that the plural lines are seen in a projection direction. In the magnetic resonance imaging apparatus, the lines are set at a matrix in which a phase direction is defined as a row direction and the projection direction is defined as a column direction. A plurality of the lines at which a predetermined number of column intervals are defined as mutual intervals are set in the respective rows. One line is set to each column.

Abstract: A current lead for the superconducting magnet of a magnetic resonance system, the superconducting magnet being refrigerated by a cold head, has a positive current lead and a negative current lead electrically connected to the superconducting magnet for magnetization thereof. The cold head is electrically connected to the superconducting magnet and is used as one of the positive and negative current leads. The cold head is used as the positive current lead or the negative current lead so as to reduce the number of current leads as well as the heat conducted by the current lead, therefore it maintains a stable superconducting environment more efficiently. Furthermore, the cold head and the current lead can be provided in the same conduit without the need to design a separated turret tube and side tube, and the structure of the current leads of the superconducting magnet of the magnetic resonance system is simplified.

Abstract: A method for determining skin factor of a subsurface rock formation from within a wellbore drilled therethrough includes measuring a nuclear magnetic resonance property of the formation at a plurality of lateral depths therein. The measured nuclear magnetic resonance property is used to estimate the skin factor.

Abstract: An inspection system positions a balancing shim to asymmetrically balance a magnetic field generated by an inductive sensor, which forms part of the inspection system. Additionally, relays and capacitors used to tune the inductive sensor to a desired resonance frequency are geometrically arranged to minimize electrical interference generated by operation of the relays and capacitors. A shielding device, which may be formed on a printed circuit board, protects a magnetic field generated by the inductive sensor from external electromagnetic interference. A slot positioned in the inductive sensor may be used to tune a resonant mode of the inductive sensor to accurately and particularly detect metallic shanks and/or other metallic objects in shoes, socks, and/or clothing.

Abstract: A medical apparatus includes a medical assist device to process signals to relating biological functions. A first lead is operatively connected to the medical assist device, the first lead having a distal end and a proximal end. A second lead is operatively connected to the medical assist device, the second lead having a distal end and a proximal end. The first electrode is operatively connected to the distal end of the first lead, and a second electrode is operatively connected to the distal end of the second lead. A filter circuit is operatively connected near the distal end of the first lead and the distal end of the second lead. A compensation circuit, operatively connected to the first lead, provides a compensation voltage to enable the filter to effectively block changing magnetic fields induced current in the second lead from passing through the second electrode of the distal end of the second lead.

Abstract: Example systems, methods, and apparatus control a pMRI apparatus to produce a pulse sequence having an extended acquisition window, and overlapping phase-encoding gradients and read gradients. One example method controls a pMRI apparatus to produce a trajectory having Cartesian and radial segments that sample in a manner that satisfies the Nyquist criterion in at least one region of a volume to be imaged. The pMRI apparatus is controlled to apply radio frequency energy to the volume according to the pulse sequence and following the trajectory and to acquire MR signal from the volume in response to the application of the RF energy. The MR signal includes a first component associated with the Cartesian segment of the trajectory and a second component associated with the radial segment of the trajectory. The example method includes calibrating a reconstruction process using Nyquist-satisfying data from the second component.

Abstract: A method of comparing micro-electronic devices. The method includes: placing a first micro-electronic device in a sample chamber of a magnetic resonance imaging machine, subjecting the first micro-electronic device to a magnetic field and a radio frequency pulse, turning off or adjusting the magnetic field and detecting a first returned RF pulse from the first micro-electronic device and storing first data relating to the first returned RF pulse; placing a second micro-electronic device in the sample chamber, subjecting the second micro-electronic device to the magnetic field and the radio frequency pulse, turning off or adjusting the magnetic field and detecting a second returned RF pulse from the second micro-electronic device and storing second data relating to the second returned RF pulse; and comparing the first data to the second data and determining if the second micro-electronic device is essentially identical to the first micro-electronic device based on the comparing.