Abstract: In one aspect the disclosed technology relates to embodiments of a method (e.g., for automatic cine DENSE strain analysis) which includes acquiring magnetic resonance data associated with a physiological activity in an area of interest of a subject where the acquired magnetic resonance data includes one or more phase-encoded data sets. The method also includes determining, from at least the one or more phase-encoded data sets, a data set corresponding to the physiological activity in the area of interest where the reconstruction comprises performing phase unwrapping of the phase-encoded data set using region growing along multiple pathways based on phase predictions.

Abstract: Method and apparatus for hardware coil compression is disclosed. The coils in an array configured for the same region of interest are grouped into sub-arrays. The coils of each sub-array are pre-combined with a hardware combiner before further processing. The pre-combination converter composed of the pre-combiners is flexible, i.e., applicable to for example non-cylindrical coils; simpler than direct implementation of the software compression algorithm; and commercially feasible.

Abstract: In one embodiment, a magnetic resonance imaging apparatus includes memory circuitry configured to store a predetermined program; and processing circuitry configured, by executing the predetermined program, to set an FSE type pulse sequence in which an excitation pulse is followed by a plurality of refocusing pulses, the plurality of the refocusing being divided into at least a first pulse group subsequent to the excitation pulse and a second pulse group subsequent to the first pulse group, the first pulse group including refocusing pulses having a predetermined high flip angle, and the second pulse group including refocusing pulses having flip angles decreased from the predetermined high flip angle toward a flip angle of zero, and generate an image of an object from respective MR signals corresponding to the plurality of refocusing pulses acquired by applying the fast spin echo type pulse sequence to the object.

Abstract: In a method and system, a reference dataset is recorded using a reference scan based on a GRE or RA RT sequence. A correction dataset is also recorded using a phase correction scan based on a non-phase-encoding EPI sequence. A measurement dataset is recorded using an SMS sequence. Slice-specific GRAPPA kernels are determined from the reference dataset and magnetic resonance images are created by a slice GRAPPA method. Data of the measurement dataset belonging to different slices is separated from one another using the slice-specific GRAPPA kernels and N/2 ghost artifacts are corrected using the correction dataset.

Abstract: A radio frequency (RF) antenna element with a (de)tuning system, with the RF antenna element having a resonant electrically conductive loop and a (de)tuning system including a photosensitive switching element to (de)tune the resonant electrically conductive loop. The (de)tuning system comprises an injection optical source optically coupled to the photosensitive switching element.

Abstract: A magnetic resonance CEST imaging sequence and device based on a frequency stabilization module are provided. It includes following steps: first, in the frequency stabilization module, exciting a target slice with a small-flip-angle radio frequency pulse, and collecting three lines of non-phase-encoded k-space data; second, obtaining an estimated value of the frequency drift of the main magnetic field by calculating the phase difference between the three lines of non-phase encoded k-space data; third, adjusting a center frequency of the radio frequency pulse based on the calculation result of the frequency drift of the main magnetic field, to realize a real-time correction of the frequency drift of the main magnetic field; and fourth, performing conventional magnetic resonance CEST imaging.

Abstract: Techniques are disclosed for acquiring MR signals of an object under examination in an MR system using a multi echo imaging sequence. The method comprises the steps of applying an RF excitation pulse to the object to generate a transverse magnetization, applying at least two RF refocusing pulses for refocusing the transverse magnetization to generate at least two MR spin echoes for the RF excitation pulse, applying a first magnetic field gradient in a read out direction between the RF excitation pulse and the first of the at least two RF refocusing pulses, applying a second magnetic field gradient in the read out direction after each of the at least two RF refocusing pulses such that the zeroth and first gradient moment is substantially zero for the second magnetic field gradient, and acquiring the at least two MR spin echoes during the at least two second magnetic field gradients.

Abstract: The invention relates to a method of Dixon-type MR imaging. It is an object of the invention to provide an MR imaging technique using bipolar readout magnetic field gradients with an improved estimation of the main field inhomogeneity to eliminate residual artifacts.

Abstract: Provided is a new scheme for applying a CS technology in a technology for imaging a target tissue based on a difference from a reference image or a control image. In this way, an imaging time is shortened. A measurement unit of an MRI apparatus executes a first imaging sequence and a second imaging sequence having different contrasts for a target, and measures a nuclear magnetic resonance signal from a subject in each of the imaging sequences. In the second imaging sequence, under-sampling is performed, and a nuclear magnetic resonance signal having a small number of samples is measured. The image processing unit restores measurement data including a nuclear magnetic resonance signal obtained by under-sampling using compressed sensing. At this time, data restoration including a term for minimizing an L1 norm is performed for a difference image between an image obtained by execution of the first imaging sequence and an image obtained by execution of the second imaging sequence.

Abstract: The invention provides for a magnetic resonance imaging system (100) comprising a main magnet (104) for generating a main magnetic field within an imaging zone (108). The magnetic resonance imaging system further comprises an RF coil (114) for acquiring magnetic resonance data (164) from the imaging zone, wherein the RF coil comprises multiple RF ports (124, 412, 414, 416, 500, 502, 702, 1004, 1006). The RF coil comprises a switch unit (120) for at least one of the multiple RF ports to individually couple or uncouple the at least one of of the multiple RF ports from the RF coil. The magnetic resonance imaging system further comprises a radio-frequency system (125) for supplying radio-frequency power to each of the multiple RF ports and an RF matching detection system (122) for measuring impedance matching data (166) between the radio-frequency system and the RF coil.

Abstract: Magnetic resonance (MR) data are acquired from a volume segment of an examination object and an MR image composed of multiple image pixels is reconstructed therefrom. For a magnetic field assumed to have been generated by the scanner, a summed field deviation is calculated, from which a respective displacement vector is calculated for each image pixel. A signal portion is assigned to each image pixel that has been displaced with the respective displacement vector from the respective image pixel. The summed field deviation is the sum of deviations caused by at least two of: non-linearities in gradient coils, Maxwell fields, field inhomogeneities independent of the gradients, and dynamic field disturbances.

Abstract: The present invention relates to a method for acquiring data for acquiring an arteriogram and a venogram of magnetic resonance imaging, the method: using one or more echo; and simultaneously acquiring, through one-time photography, an arteriogram and a venogram, which are optimized according to the number of slabs or improving connectivity of a slab boundary part of the arteriogram.

Abstract: A magnet assembly in a magnetic resonance apparatus includes a cryostat and a superconducting main field magnet coil system arranged therein for generating a magnetic field in the direction of a z-axis in a working volume. The magnet assembly includes a shim device arranged inside the cryostat for adjusting the spatial variation or homogeneity of the magnetic field generated in the working volume by the magnet coil system. The shim device comprises at least one closed superconducting shim conductor path having an HTS layer. The HTS layer forms a surface that is geometrically developable such that unwrapping onto a plane changes the geodesic distance between any two points on the surface formed by the HTS layer by no more than 10%. The inner and/or outer contour of the geometrical development of the HTS layer describes a non-convex curve.

Abstract: A single-layer magnetic resonance imaging (MRI) radio frequency (RF) coil element configured to operate in a transmit (Tx) mode and a receive (Rx) mode, the coil element comprising: an LC coil and a failsafe circuit electrically connected with the LC coil, where the LC coil, upon resonating with a primary coil of an MRI system, generates a local amplified Tx field based on an induced current generated in the LC coil by inductive coupling between the LC coil and the primary coil, where the failsafe circuit provides, upon injection of a forward DC bias current into the failsafe circuit, a first impedance, and upon the absence of the forward DC bias current, a second, higher impedance; where the failsafe circuit, upon the single-layer MRI RF coil array element being disconnected from an MRI system, provides the second, higher impedance, and reduces the magnitude of the induced current.

Abstract: A gradient coil assembly for a magnetic resonant apparatus has a primary coil and a secondary coil, wherein the primary coil has a first primary coil winding and a second primary coil winding, wherein the first primary coil winding and the second primary coil winding are electrically connected to a voltage source and are jointly designed to generate a magnetic field gradient in a direction when the voltage source induces a current in those windings.

Abstract: The present disclosure relates to a control system and methods implemented on the control system. The control system includes a tuning/detuning system and a diagnosis system. The tuning/detuning system includes a first voltage source, a second voltage source, one or more coil arrays, and one or more tuning/detuning circuit drivers corresponding to the one or more coils arrays, respectively. The diagnosis system includes a first current sampling circuit and a processor. The first current sampling circuit is configured to obtain a first current. The processor is configured to diagnose the tuning/detuning system based on the first current.

Abstract: An apparatus for performing a downhole nuclear magnetic resonance (NMR) experiment on a subsurface material in a volume of interest includes: a carrier configured to be conveyed through a borehole penetrating the subsurface material; an NMR sensor assembly disposed on the carrier and comprising a static magnetic field source configured to polarize nuclei of the subsurface material in the volume of interest and an antenna configured to receive NMR signals; and a receiver circuit disposed on the NMR sensor assembly and configured to process received NMR signals to perform the downhole NMR experiment; wherein (i) the receiver circuit is disposed in a pressure-excluding enclosure and (ii) the antenna, the static magnetic field source, and the pressure-excluding enclosure are disposed in a pressure-balancing fluid that is at least partially enclosed by an enclosure of non-metallic material.

Abstract: In a method and magnetic resonance imaging apparatus having a scanner that for acquires a magnetic resonance dataset, a magnetic resonance sequence is provided to a computer and is converted in the computer into a digital sequence execution signal that includes a target gradient waveform in the form of a time-discrete target gradient signal the computer calculates a pre-GIRF gradient signal by applying a digital pre-emphasis filter to the target gradient signal. The computer transmits the pre-GIRF gradient signal to the magnetic resonance system scanner and) the scanner executes the digital sequence execution signal containing the pre-GIRF gradient signal in order to acquire magnetic resonance raw data.

Abstract: A radio frequency (RF) coil and a magnetic resonance imaging (MRI) system including the same are provided. The RF coil may include at least one RF coil element formed on a base of a cylindrical shape having a circular or oval cross-sectional shape, wherein coil elements of a first end portion and a second end portion of the at least one RF coil element have regions surrounding an outer circumferential portion of the base and bent in a z axis direction. The at least one RF coil element may include a first RF coil element and a second RF coil element.

Abstract: A method and system for nuclear magnetic resonance (NMR) sequence for partially polarized echo trains is provided. An NMR pulse sequence is applied into a wellbore penetrating a subterranean formation using a NMR tool. The NMR pulse sequence includes a first cycle and a second cycle. The first cycle includes a first sequence of radio frequency (RF) pulses of a first duration and a first trainlet sequence of a second duration different from the first duration. The second cycle includes a second sequence of RF pulses of the first duration and a second trainlet sequence of the second duration. The second sequence of RF pulses forms a phase alternated pair with the first sequence of RF pulses. Echo signals corresponding to a substance in the subterranean formation are measured based on the NMR pulse sequence. A distribution of a characteristic of the substance is determined based on the echo signals.