Abstract: The MRI apparatus of the present invention executes a non-imaging mode 501 for obtaining a steady state of magnetization and an imaging mode 502 for measuring echoes for images. In the non-imaging mode 501 and the imaging mode 502, imaging is performed by using a GrE type pulse sequence. In the imaging, RF pulses are irradiated while flip angle of nuclear magnetization in the imaging mode 502 is changed in a range of values not larger than a certain value determined by flip angle of nuclear magnetization used in the non-imaging mode 502 is irradiated. This certain value is, for example, the maximum value of flip angle of nuclear magnetization used in the non-imaging mode, or flip angle provided by an RF pulse used at the end of the non-imaging mode. SAR observed with use of a GrE type pulse sequence can be thereby reduced without degrading image contrast, and thus influence on human bodies can be reduced.

Abstract: In a method to determine a phase position of a magnetization that is caused by radiation of an adiabatic RF pulse for the acquisition of magnetic resonance signals from a slice of an examination subject, an RF pulse of a first type is radiated and a first magnetic resonance signal is acquired, an adiabatic RF pulse is radiated and a second magnetic resonance signal is acquired, the phase of a magnetization induced by the RF pulse of the first type is calculated, as a first phase, and the phase of a magnetization induced by the adiabatic RF pulse is calculated as a second phase, and the phase position of the second phase in relation to the first phase is determined.

Abstract: A system and method for determining the temporal resolution of a tomographic imaging device uses an apparatus to drive one or more dynamic phantoms composed of multiple materials. The apparatus is placed at or near the isocenter of the imaging device and the one or more phantoms are moved to produce a plurality of dynamic features, each having a specified frequency. The dynamic features are imaged with the device and the acquired image data corresponding to the dynamic features is analyzed to determine a temporal modulation transfer value at each of the known specified frequencies. The temporal resolution of the imaging device is determined using these temporal modulation transfer values.

Abstract: Example systems, methods, and apparatus facilitate providing a k-space line that is missing in an under-sampled time frame. The missing line is computed by applying a GRAPPA-operator to a known k-space line in the under-sampled time frame. One example method includes controlling a dynamic parallel magnetic resonance imaging (DpMRI) apparatus to acquire a first under-sampled time interleaved frame having at least one first k-space line and controlling the DpMRI apparatus to acquire a second under-sampled time interleaved frame having at least one second k-space line that neighbors the first k-space line. The method includes assembling a reference data set from the first under-sampled time frame and the second under-sampled time frame and then determining the GRAPPA-operator from neighboring k-space lines in the reference data set.

Abstract: A magnet structure for an MRI apparatus utilizing a permanent magnet, which apparatus has an inverted U shape with two essentially parallel opposed pole pieces, which are supported at a predetermined distance from each other by an inverted U-shaped magnetic yoke, which pole pieces and/or at least a portion of which yoke delimit a cavity for receiving at least a part of the patient's body, whereas a partial volume is generated in the volume of said cavity, which has such magnetic field values as to provide MRI images of a sufficient quality to enable the use thereof as diagnostic images, i.e. a so-called imaging volume. According to the invention, the distance (D1) between the pole pieces (1, 2) of the magnet structure is of 36 to 42 cm, and the pole pieces (1, 2) have a surface area of 4500 to 5500 cm2. The invention also relates to an MRI imaging apparatus, particularly designed for the spine region, or a part thereof, and which has a magnet structure as described above.

Abstract: In a method, apparatus and computer-readable medium for magnetic resonance imaging of a contiguous region of a human body on the basis of partially parallel acquisition (PPA) by excitation of nuclear spins and measurement of radio-frequency signals representing the excited spins, are implemented. A k-space single channel reference image [R_kal] is calculated from the previously measured reference lines of a sub-coil series of N sub-coils with a phase-sensitive combination method. A GRAPPA coefficient matrix [W] is calculated by solving the equation system [R_kal]=[W]×[I_kal] wherein [I_kal] represents one block from the sub-coil series. A k-space single channel image [R] is successively completed by applying [W] to successive blocks [I_z] shifted relative to one another, the blocks [I_z] being of a previously measured, under-sampled sub-coil series of the N sub-coils, and [R] is transformed into image space.

Abstract: New MRI coil and resonators are disclosed based solely on superconducting inductive element and built-in capacitive elements as well as hybrid superconducting-metal inductive and capacitive elements having superior SNR. Single and multiple small animal MRI imaging units are also disclosed including one or more resonators of this invention surrounding one or more small animal cavities. Methods for making and using the MRI coils and/or arrays are also disclosed.

Abstract: A nuclear magnetic resonance sensing apparatus and method for operating in an earth borehole comprises a source of switchable magnetic field to polarize nuclei in the region of interest, said source comprising a coil wound on a magnetic core having controllable residual magnetization. Maintaining the magnetization of the core during a polarization interval does not require steady current in the coil. Switching intensity and polarity of magnetization of the core causes precession of spin magnetic moments of the nuclei; the precession induces a signal indicative of nuclear magnetic resonance properties of earth formations.

Abstract: An NMR apparatus is provided, which is capable of being used for mass spectrometry and structure determination of a gas sample.

Abstract: A receiving device for an MRI (magnetic resonance imaging) system has multiple receiving coils. In the same imaging acceleration direction, a junction region is formed between adjacent receiving coils. An additional receiving coil is arranged on the junction region. The additional receiving coil covers at least partially a line of strong phase variation in sensitivity at the boundary of said junction region. This receiving device alleviates the problem of poor sensitivity to MRI signals in the junction region in the imaging acceleration direction, so as to improve the imaging quality in the junction region, and thus improving the overall imaging quality.

Abstract: In a magnetic resonance scanner, a main magnet (20, 22) generates a static magnetic field at least in an examination region. A magnetic field gradient system (30, 54) selectively superimposes magnetic field gradients on the static magnetic field at least in the examination region. A magnetic resonance excitation system (36, 36?) includes at least one radio frequency coil (30, 301, 302, 303) arranged to inject radio frequency B1 fields into the examination region and at least two radio frequency amplifiers (38, 40, 40?) coupled with different input ports of the at least one radio frequency coil. A controller (66, 70) controls the magnetic resonance excitation system to produce a time varying spatial B1 field distribution in a subject (16) in the examination region that time integrates to define a spatial tip angle distribution in the subject having reduced spatial non uniformity.

Abstract: Through modification of the phase-encoding gradient, a method and apparatus increases the effectiveness of a Magnetic Resonance Imaging (MRI) device by decreasing scan time without noticeably decreasing the signal-to-noise ratio. In an MRI device, a patient is subjected to a constant magnetic field, and then radio frequency (RF) pulses are used to excite the nuclei in the patient's body. The nuclei release a corresponding RF signal as the nuclei relax, which can be measured and mapped into a visual display. The RF pulses used to excite the nuclei in the body cooperate with a slice select gradient and a phase-encoding gradient. When the phase-encoding gradient is indexed and prioritized according to contribution to image quality, then phase-encoding values with little or no contribution to image quality need not be acquired but may be replaced with randomized system noise, thereby decreasing total scan time without reducing the signal-to-noise ratio.

Abstract: Methods, systems, software arrangements and storage medium for measuring the magnetic field correlation function (“MFC”), and more particularly, to methods for measuring the magnetic field correlation function utilizing asymmetric spin echoes. Asymmetric Dual Spin Echo Sequences (“ADSE”) and Echo Planar Imaging Asymmetric Dual Spin Echo Sequences (“EPI-ADSE”) may be employed to apply multiple echoes to a sample and acquire data from which the MFC may be determined.

Abstract: A method and apparatus useful to determine characteristics of fluid flow, such as fluid holdup and flow velocity. The apparatus comprises a flow tube, a permanent magnet, a first set of coils, and a second set of coils. The first set of coils creates a radio frequency magnetic field within the flow tube with a series of refocusing pulses. The second set of coils encodes velocity information onto the fluid molecules using rotating frame zeugmatography that is later decoded and used to estimate the fluid flow velocity.

Abstract: A remote control system for a modulatable device is provided. The remote control system comprises a receiver system coupled to the modulatable device and configured to obtain an output characteristic of the modulatable device, the receiver system being located remotely with respect to the modulatable device. The system further comprises a command signal setting system coupled to the receiver system and configured to use the output characteristic to generate a drive command signal and a bias system coupled to the command signal setting system and configured to receive the drive command signal and set a bias point of the modulatable device based on the drive command signal. The bias system is located locally with respect to the modulatable device. The command signal setting system and the bias system are coupled via a first optical conduit.

Abstract: A apparatus for low AC loss thermal shielding includes a plurality of thermally conducting fibers positioned along a desired direction of heat conduction. The fibers are electrically insulated from each other. The fibers are bonded together with a matrix, and a thermal link connects the bonded fibers to a cryogenic cold head.

Abstract: An MRI apparatus excellent in magnetic field generation efficiency is provided. According to this invention, a main coil (52) of a gradient magnetic field coil (13) is partially recessed to reduce the total thickness of a radio-frequency coil (11) and a gradient magnetic field coil (13). That is, the main coil (52) is designed in a tubular shape, and the diameter r1 at the center portion of the imaging space is larger than the diameter r2 of the main coil end portion. Accordingly, the RF coil (11) can be disposed to be near to the gradient magnetic field coil (13) side without lowering the magnetic field generation efficiency.

Abstract: A magnet which includes ferromagnetic powder to be mainly a mother phase containing iron or cobalt. The ferromagnetic powder is provided with a high-resistance layer which has a resistance higher than or equal to ten times as high as a resistance of the mother phase and a Vickers hardness lower than a Vickers hardness of the mother phase. The high-resistance layer is being formed partially or entirely on the surface of the ferromagnetic powder.

Abstract: At least one embodiment is directed to a combination of an MR tomograph and a positron emission tomograph having avalanche photodiodes as reception elements. In at least one embodiment, the intention is to ensure that the avalanche photodiodes are kept at a constant temperature despite the exposure to heat from the MR components. It is proposed, in at least one embodiment, that cooling by Peltier elements 5 should be provided.

Abstract: A control device for a magnetic resonance system activates the coils of a transmission array and a gradient magnet system of the magnetic resonance system by causing an excitation pulse to be supplied to each coil. A magnetization that exhibits a first actual inhomogeneity thereby is generated in an excitation volume of the magnetic resonance system. The control device determines the excitation pulse for each coil using a start pulse and a maximum allowable inhomogeneity. The respective start pulse has a total time duration. When the control device activates the coils of the transmission array and of the gradient magnet system corresponding to the start pulse, a magnetization that exhibits a second actual inhomogeneity that is smaller than the maximum permissible inhomogeneity is generated in the excitation volume.