| Class / Patent application number | Description | Number of patent applications / Date published |
|---|
| 324314000 | With conditioning of transmitter signal | 59 |
| 20080231276 | MAGNETIC RESONANCE SYSTEM WITH RADIO-FREQUENCY SHIELD WITH FREQUENCY-DEPENDENT SHIELDING EFFECT - A magnetic resonance system has a basic magnet that generates a static basic magnetic field in an examination volume, and a whole-body antenna that emits a homogeneous radio-frequency field in the examination volume, the homogeneous radio-frequency field exhibiting an excitation frequency so that nuclei in an examination subject in the examination volume are excited to emit magnetic resonance signals, and a radio-frequency shield. The radio-frequency shield is arranged between the whole-body antenna and the basic magnet. The whole-body antenna is arranged between the radio-frequency shield and the examination volume. The radio-frequency shield is fashioned to exhibit a high shielding effect in a shielding frequency range that encompasses the excitation frequency. The shielding effect drops to a significantly lower shielding effect on both sides at side bands adjoining the shielding frequency range. The shielding frequency range and the side bands exhibit bandwidths that are significantly smaller than the excitation frequency. | 09-25-2008 |
| 20080272783 | MAGNETIC RESONANCE IMAGING APPARATUS AND MAGNETIC RESONANCE IMAGING METHOD - A magnetic resonance imaging apparatus that applies a gradient magnetic field and a radio-frequency magnetic field to a subject in a static magnetic field to image the subject based on magnetic resonance signals emitted from the subject, includes a unit which generates K transmission radio-frequency pulse signals required to produce the radio-frequency magnetic field, an allocation unit which allocates the K transmission radio-frequency pulse signals to K in M transmission signal paths, a connection unit to which at most M radio-frequency coils are attachable and which selectively connects the M transmission signal paths and M reception signal paths to the radio-frequency coils, a selection unit which selects N in magnetic resonance signals which are respectively received by the at most M radio-frequency coils and transmitted through the at most M reception signal paths, and a unit which performs reception processing for each of the selected N magnetic resonance signals. | 11-06-2008 |
| 20080309338 | MRI APPARATUS AND RF TRANSMIT GAIN SETTING METHOD - An MRI apparatus which obtains a tomogram of an object by utilizing magnetic resonance includes a calibrating device which figures out a relationship between a center frequency and an optimal gain of RF transmission with respect to a predetermined range of central frequencies, a saving device which saves information expressing said relationship, and a setting device which sets the RF transmission gain according to the center frequency during subsequent scanning by utilizing the saved information. | 12-18-2008 |
| 20090256569 | MULTI-FREQUENCY RF COIL - A multi-frequency imaging radio frequency (RF) coil operational at three or more different frequencies, with a shifting frequency loop structure proximate the coil and switchably coupled to provide different frequencies when the loop structure is coupled to the coil. In one embodiment one of the frequencies is a proton frequency, one is a sodium frequency, and one of the frequencies is a carbon frequency. One example involves imaging examinations using hyperpolarized compounds. | 10-15-2009 |
| 20090256570 | Method For Joint Sparsity-Enforced K-Space Trajectory and Radiofrequency Pulse Design - A system and method is provided for simultaneously designing a radiofrequency (“RF”) pulse waveform and a magnetic field gradient waveform in a magnetic resonance imaging (“MRI”) system. The method includes determining a desired pattern of RF excitation and determining, from the desired pattern of RF excitation, a plurality of k-space locations indicative of the magnetic field gradient waveform and a plurality of complex weighting factors indicative of RF energy deposited at each k-space location. The method also includes calculating, from the determined k-space locations, the magnetic field gradient waveform and calculating, from the complex weighting factors, the RF pulse waveform that will produce the desired pattern of RF excitation when produced with the calculated magnetic field gradient. | 10-15-2009 |
| 20090273346 | APPARATUS AND METHOD FOR OPTIMIZING THE SPECTRA OF PARALLEL EXCITATION PULSES - An MRI apparatus includes a magnetic resonance imaging (MRI) system having a magnet to impress a polarizing magnetic field, a plurality of gradient coils positioned about the bore of the magnet to impose a magnetic field gradient, and an RF transceiver system and an RF switch controlled by a pulse module to transmit RF pulses to an RF coil assembly and to acquire MR images, and a computer programmed to apply a plurality of RF pulses configured to control RF excitation by a transmit coil array such that a waveform shape of each of the plurality of RF pulses is based on optimizing a spatial spectrum. | 11-05-2009 |
| 20100019766 | System for Dynamically Compensating for Inhomogeneity in an MR Imaging Device Magnetic Field - A system automatically dynamically compensates for inhomogeneity in an MR imaging device magnetic field. An MR imaging compensation system applies swept frequency magnetic field variation in determining an estimate of proton spin frequency at multiple individual locations associated with individual image elements in an anatomical volume of interest and substantially independently of tissue associated relaxation time. For the multiple individual locations, the system determines an offset frequency comprising a difference between a determined estimate of proton spin frequency associated with an individual image element location and a nominal proton spin frequency. The system derives data representing an electrical signal to be applied to magnetic field generation coils to substantially compensate for determined offset frequencies at the multiple individual locations. An MR magnetic field coil generates a magnetic field in response to applying the electrical signal to substantially compensate for magnetic field variation represented by the determined offset frequencies at the multiple individual locations. | 01-28-2010 |
| 20100141257 | RF TRANSMITTER WITH DIGITAL FEEDBACK FOR MRI - A method and an RF transmit system for generating RF transmit signals for feeding an RF transmitter ( | 06-10-2010 |
| 20100194391 | COMPENSATION DEVICE TO REDUCE THE ELECTROMAGNETIC FIELD LOAD DUE TO A MEDICAL INTERVENTION APPARATUS IN MAGNETIC RESONANCE EXAMINATIONS - A compensation device to reduce the electromagnetic field load due to the presence of a medical intervention apparatus in magnetic resonance examinations, has: a control device that has a radio-frequency input and a radio-frequency output, an injection device that is connected with the radio-frequency output and that injects the radio-frequency power delivered by the control device into the medical intervention apparatus, a measurement device that measures at least one electrical variable at the intervention apparatus, and a regulator that is connected with the control device and the measurement device. The regulator adjusts the control device to deliver the radio-frequency power so that the electrical variable at the intervention apparatus is reduced. | 08-05-2010 |
| 20100201363 | CALIBRATING PARALLEL MRI WITH CARTESIAN CONTINUOUS SAMPLING - 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 non-Cartesian 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 non-Cartesian segment of the trajectory. The example method includes calibrating a reconstruction process using Nyquist-satisfying data from the second component. | 08-12-2010 |
| 20100201364 | PHASE CORRECTION METHOD - A method corrects for a phase error in an MR image, in which MR signals of an examination subject are acquired, complex images of the examination subject are generated, phase differences of the phase values for various image points of the complex images are established with an averaged phase value of image points from a first surrounding region of a respective image point, and a phase correction is executed dependent on how well the phase differences correspond to a predetermined phase value, where the order of the image points in which the phase correction is implemented is dependent on how well the phase values in the image points correspond to the predetermined phase value. | 08-12-2010 |
| 20100207630 | PASSIVE SHIMMING OF MAGNET SYSTEMS - In a method and an arrangement for shimming a cylindrical magnet system, that has a cylindrical magnet having a bore therein with an axis extending therethrough, and a gradient coil assembly located within the bore, shimming is accomplished by stacking a number of planar pieces of shim material in each of said tubes, with each of the tubes having an axis parallel to the axis of the cylindrical magnet, and with the planar pieces of shim material and stacked in the tubes in respective planes that are perpendicular to the axis of the cylindrical magnet. | 08-19-2010 |
| 20100237867 | Arrangements and Method for Shimming a Magnetic Field - A shim arrangement for increasing the homogeneity of a magnetic field within a homogeneous field region, comprising: shim channels extending within a volume between a magnetic field generator and the homogeneous field region; at least one piece of shim material located within each shim channel; an arrangement for moving each shim piece along the corresponding shim channel; and retaining means for retaining each shim piece in position. Shimming is performed by moving shim pieces within the shim channels, with the magnet at field. No shim pieces are added to, or removed from, the shim channels during the shimming step. | 09-23-2010 |
| 20100271025 | Device for highly precise synchronization of the NMR transmission frequency to the resonance frequency of an NMR line while taking into consideration a non-constant RF phase - A device that comprises an RF generator ( | 10-28-2010 |
| 20100308829 | METHOD AND SYSTEM FOR MODIFYING PULSE SEQUENCES - Methods and systems are provided for modifying a pulse sequence. In one embodiment, a determination is made whether an estimated peripheral nerve stimulation (PNS) associated with a pulse sequence exceeds a PNS limit. If the estimated PNS exceeds the PNS limit, a slew rate associated with one or more axes of the pulse sequence may be reduced and the maximum gradient amplitudes for each axis of the pulse sequence may be adjusted. In one embodiment, adjustment of the maximum gradient amplitudes or local slew rate may be based upon a cost analysis performed on the pulse sequence. | 12-09-2010 |
| 20110234228 | MAGNETIC RESONANCE SYSTEM AND METHOD TO CREATE A MAGNETIC RESONANCE IMAGE DATA SET BY RADIAL SCANNING OF A MAGNETIC RESONANCE SYSTEM - 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. | 09-29-2011 |
| 20110267056 | DIGITAL WAVEFORM SYNTHESIZER FOR NMR PHASE CONTROL - In an RF source, a digital waveform synthesizer comprises a computational module to synchronously determine a desired periodic function, f(θ), within a first bandwidth portion, to which computational result there is combined an injected digital noise increment in an adjustable range of bounded amplitude, specifically selected to average over discontinuities of the DAC transfer characteristic. The combination is effected after passing the injected noise increment through a programmable digital filter forming a composite tuning word having a total bandwidth at a selected Nyquist zone and thence passing the composite tuning word through a truncation component to a DAC. The programmable digital filter is constructed to displace the spectral distribution of the injected noise increment to a portion of the total bandwidth remote from the first bandwidth portion. | 11-03-2011 |
| 20110267057 | DYNAMIC FREQUENCY DRIFT CORRECTION METHOD IN MAGNETIC RESONANCE IMAGING - For magnetic resonance imaging (MRI), a dynamic frequency drift correction method for binomial water excitation method includes collecting the reference one-dimensional navigation signal by an MRI device; acquiring one current one-dimensional navigation signal after scanning N images, wherein N is a positive integer; calculating the frequency drift according to the reference one-dimensional navigation signal and the current one-dimensional navigation signal; calculating and setting the initial phase of the next radio frequency signal by the MRI device according to the frequency drift. The method provides real-time calculation of the main magnetic field frequency drift according to the one-dimensional navigation signal during the scanning period and corrects the phase of the radio frequency signal to ensure that the direction of the gradient field is always perpendicular to the plane formed by the spinning of fat protons, so there is only water signal remaining after excitation so that water images can be obtained. | 11-03-2011 |
| 20110304333 | Means And Methods For Providing High Resolution MRI - Means and methods for improving the MRI “image quality in an MRI imaging” apparatus comprising a non-super-conducting electromagnet and a plurality of pole pieces are provided. Said means for improving the image quality chosen from the group consisting of (a) means for reducing degradation of MRI image quality due to B | 12-15-2011 |
| 20110304334 | MAGNETIC RESONANCE METHOD AND APPARATUS TO CORRECT IMAGE DISTORTIONS IN DIFFUSION-WEIGHTED IMAGING - In a magnetic resonance (MR) apparatus and an operating method for the apparatus, image distortions are corrected that occur in exposures of diffusion-weighted MR images of an examination subject. | 12-15-2011 |
| 20120001635 | MAGNETIC RESONANCE IMAGING APPARATUS AND MAGNETIC RESONANCE IMAGING METHOD - In one embodiment, an MRI apparatus includes a temperature measuring unit, a data storing unit, a pulse setting unit and an imaging unit. | 01-05-2012 |
| 20120043965 | MAGNETIC RESONANCE IMAGING SYSTEM AND METHOD EMBODYING A MAGNETIC RESONANCE MARKING SYSTEM AND METHOD - In a magnetic resonance marking system marking a flowing medium in a marking region, as well as in a magnetic resonance system with such a magnetic resonance marking system, a method to control a magnetic resonance marking system, and a method to generate magnetic resonance exposures, a radio-frequency transmission device generates marking radio-frequency signals, and a marking radio-frequency transmission coil emits the marking radio-frequency signals in the marking region. A magnetic field determination device determines a magnetic field strength in the marking region, and a control unit derives a marking transmission frequency from the determined magnetic field strength and to control the radio-frequency transmission device so that marking radio-frequency signals at the derived marking transmission frequency are emitted by the marking radio-frequency transmission coil. | 02-23-2012 |
| 20120074940 | MAGNETIC RESONANCE IMAGING APPARATUS AND MAGNETIC RESONANCE IMAGING METHOD - According to one embodiment, a magnetic resonance imaging apparatus includes an imaging unit and data processing condition setting unit. The imaging unit is configured to acquire magnetic resonance data corresponding to a sampling region asymmetric in a wave number direction in k-space from an object to generate image data based on the magnetic resonance data by data processing including phase correction and filter processing for obtaining a complex conjugate. The data processing condition setting unit is configured to set a condition for the data processing according to an imaging condition influencing a phase distribution used for the phase correction or the phase distribution. | 03-29-2012 |
| 20120074941 | METHOD FOR SUPPRESSING AND/OR ELIMINATING NOISE SIGNALS IN MAGNETIC RESONANCE IMAGING AND A MAGNETIC RESONANCE APPARATUS THEREFOR - A method is disclosed for suppressing and/or eliminating noise signals during magnetic resonance imaging by way of a magnetic resonance sequence including an ultra-short echo time. In at least one embodiment, the method includes a recording step for recording magnetic resonance signals of an object to be examined, especially a partial region of a patient, by way of the magnetic resonance sequence, wherein in a noise signal determination step at least one item of information about at least one noise signal of a noise element, especially of a magnetic resonance antenna element, is made available. | 03-29-2012 |
| 20120081116 | MAGNETIC RESONANCE IMAGING APPARATUS AND MAGNETIC RESONANCE IMAGING METHOD - According to one embodiment, a MRI apparatus includes a data acquisition unit, a phase correction amount calculation unit and an image data generating unit. The data acquisition unit acquires MR signals in 3D k-space according to an imaging condition for HFI. The phase correction amount calculation unit calculates a first phase correction amount by applying processing including a phase correction based on k-space data for calculating the first phase correction amount and data compensation for a non-sampling region with the MR signals in the 3D k-space. The k-space data for calculating the first phase correction are MR signals less than the MR signals in the 3D k-space. The image data generating unit generates MR image data by applying processing including a phase correction using a second phase correction amount based on the first phase correction amount and the data compensation with the MR signals in the 3D k-space. | 04-05-2012 |
| 20120153952 | METHOD AND SYSTEM FOR GRADIENT LINEAR CORRECTION - Methods, systems and computer program products are described for providing gradient linearity correction in a magnetic resonance image. The method in one example obtains, using a simulation, a time-dependent eddy current induced magnetic gradient field produced by a gradient system in response to a gradient switching pulse. Subsequently, the method determines time-dependent eddy current harmonic response coefficients for at least one higher harmonic frequency based upon the time-dependent eddy current induced magnetic gradient field. The method then corrects the magnetic resonance image based upon the time-dependent eddy current harmonic response coefficients. | 06-21-2012 |
| 20120262175 | SYSTEM AND METHOD OF HIGH SIGNAL-TO-NOISE RATIO MAGNETIC RESONANCE IMAGING SCREENING - An MRI apparatus is disclosed, the MRI apparatus comprising a computer programmed to apply a fluid suppression technique prior to an imaging pulse-gradient sequence, wherein the fluid suppression technique is configured to suppress signals from fluids having long longitudinal relaxation times, and apply a fat suppression technique after the fluid suppression technique and prior to the imaging pulse-gradient sequence, wherein the fat suppression technique is configured to suppress fat signals. The computer is further programmed to apply a flow suppression preparation sequence after the fat suppression technique and prior to the imaging pulse-gradient sequence, wherein the flow suppression preparation sequence is configured to suppress moving tissue signals. The computer is also programmed to apply the imaging pulse-gradient sequence, cause the RF transceiver system to acquire MR signals during the imaging pulse-gradient sequence, and reconstruct an image from the acquired MR signals. | 10-18-2012 |
| 20120268129 | TRANSMITTING DEVICE FOR DRIVING A HIGH-FREQUENCY ANTENNA OF A MAGNETIC-RESONANCE DEVICE - A transmitting device for driving a high-frequency antenna of a magnetic-resonance device using a target signal capable of being amplitude-modulated is provided. A number N of similarly embodied amplifier modules, where N is at least two, a signal-conditioning device, and a combining device for combining output signals of the amplifier modules into the target signal are provided. The signal-conditioning device generates N drive signals having a predetermined pulse frequency that consist of pulses having a length dependent on a desired target amplitude and having a phase corresponding to the desired target phase and a frequency corresponding to the desired target frequency. The pulses of the individual drive signals are mutually offset in time by, in each case, 1/N of a pulse period corresponding to the pulse frequency. Each drive signal is fed to an amplifier module. | 10-25-2012 |
| 20130088231 | MAGNETIC RESONANCE SYSTEM AND METHOD FOR FREQUENCY CALIBRATIONN OF THE MAGNETIC RESONANCE SYSTEM - In a method for frequency calibration in a magnetic resonance system in a volume section containing an unknown number of determined substances, the predetermined volume section is excited with RF pulses and subsequent echo signals are recorded at different times and spectral information is determined for each of the echo signals, from which a peak value in the spectral information and an associated relaxation time are determined. Dependent on the relaxation time, a substance is determined for each peak value. A frequency adjustment substance dependent of the magnetic resonance system is then implemented. Multiple peak values in the spectral information of the echo signals can be determined. | 04-11-2013 |
| 20130127465 | APPARATUS AND METHOD FOR SYNCHRONIZING CLOCKS BETWEEN DEVICES OF MAGNETIC RESONANCE IMAGING (MRI) SYSTEM - A method of synchronizing clocks between a central controlling unit and a radio frequency (RF) coil which are wirelessly connected to each other in a magnetic resonance imaging (MRI) system, which includes receiving a first clock from the central controlling unit, synchronizing a second clock of the RF coil with a received first clock, and discontinuing the receiving of the first clock from the central controlling unit when the second clock is synchronized with the first clock. | 05-23-2013 |
| 20130134976 | MAGNETIC RESONANCE IMAGING APPARATUS - A magnetic resonance imaging apparatus according to embodiments includes an executing unit, an informing unit, a detecting unit, and a determining unit. The executing unit executes a pulse sequence to collect data of a subject at a constant cycle. The informing unit informs the subject of a timing of breathing in synchronization with the cycle at which the pulse sequence is executed. The detecting unit detects a breathing level or a respiratory cycle of the subject. The determining unit determines, when the pulse sequence is executed, whether to use the data collected by the pulse sequence for image reconstruction in accordance with the breathing level or the respiratory cycle of the subject. | 05-30-2013 |
| 20130154645 | MAGNETIC RESONANCE IMAGING APPARATUS AND MAGNETIC RESONANCE IMAGING METHOD - According to one embodiment, a magnetic resonance imaging apparatus includes an imaging condition setting unit and an imaging unit. The imaging condition setting unit is configured to display a setting screen of a radio frequency prepulse on a display unit to set imaging conditions including application timings of radio frequency prepulses according to input information from an input device through the setting screen. The setting screen displays an application timing of a radio frequency excitation pulse and the application timings of the radio frequency prepulses on a time axis. The imaging unit is configured to perform imaging of an object according to the imaging condition. | 06-20-2013 |
| 20130181712 | Method for Correcting Motion-Induced Phase Errors In Magnetic Resonance Imaging - A method for correcting motion-induced phase errors in diffusion-weighted k-space data acquired with a magnetic resonance imaging (MRI) system is provided. The MRI system is directed to acquire the following data from an imaging volume: three-dimensional diffusion-weighted k-space data, three-dimensional diffusion-weighted navigator data, three-dimensional non-diffusion-weighted k-space data, and three-dimensional non-diffusion-weighted navigator data. Initial estimates of k-space shift values and a constant phase offset value are calculated using the three-dimensional diffusion-weighted navigator data and the three-dimensional non-diffusion-weighted navigator data. These initial k-space shift values and constant phase offset value are then updated by iteratively minimizing a cost function that relates the phase of the diffusion-weighted k-space data to the phase of the non-diffusion-weighted k-space data, as shifted by the initial k-space shift values and constant phase offset value. The diffusion-weighted k-space data is then corrected for motion-induced phase errors using the updated k-space shift values and constant phase offset value. | 07-18-2013 |
| 20130181713 | CONTROLLING GRADIENT COILS TAKING THE INDUCTIVE COUPLING INTO ACCOUNT - A gradient pulse generator generates reference current signals for a plurality of gradient coils of a gradient coil system of a magnetic resonance system and supplies each of the reference current signals to a controller assigned to one of the gradient coils. Also supplied to the respective controller is an actual current signal that is characteristic of the current flowing in the respective gradient coil. Each of the controllers generates a control signal and accordingly drives a gradient power amplifier assigned to the respective gradient coil. The gradient power amplifiers apply a current to the gradient coils assigned to the gradient power amplifiers in accordance with the generated control signals. Each of the controllers is also supplied with the reference current signal or the actual current signal of at least one other gradient coil or the time derivative of the reference current signal or the actual current signal. | 07-18-2013 |
| 20130187653 | ACTIVATION OF FIELD COILS OF A MAGNETIC RESONANCE SYSTEM HAVING EDDY CURRENT COMPENSATION - A controller of a magnetic resonance system determines an activation signal vector based on a target field predetermined for the controller in conjunction with field characteristics of field coils known to the controller. The activation signal vector includes a respective activation signal for each field coil. The controller determines the activation signal vector such that within a predetermined examination volume of the magnetic resonance system, any deviation of an ideal field that would result if ideal coils were subjected to the activation signals of the activation signal vector from the target field is minimized. The controller determines a compensation signal vector based on the activation signal vector in conjunction with eddy current characteristics of the field coils known to the controller. The compensation signal vector is used to minimize a deviation of an actual field from the target field within the predetermined examination volume of the magnetic resonance system. | 07-25-2013 |
| 20130200893 | Determination of a Measuring Sequence for a Magnetic Resonance System - A method and a measuring-sequence-determining device for determining a measuring sequence for a magnetic resonance system based on at least one intra-repetition-interval time parameter are provided. During the determination of the measuring sequence in a gradient-optimization method, gradient-pulse parameters of the measuring sequence are automatically optimized to reduce at least one gradient-pulse-parameter maximum value. As a boundary condition in the gradient-optimization method, the intra-repetition-interval time parameter is kept constant at least within a specified tolerance value. | 08-08-2013 |
| 20130214784 | Method for Operating a Coil and a Monitoring Module - A method for operating a coil, through which a varying current flows, is provided. Mechanical resonance responses of the coil are recorded and are modeled by an electrical resonant circuit model. A check is made as to whether a varying current that is to be sent through the coil evokes a resonant response in the electrical resonant circuit model. The current flow through the coil is blocked if the resonant response exceeds a predefined limit value. | 08-22-2013 |
| 20130221964 | REDUCING NOISE IN MAGNETIC RESONANCE IMAGING USING CONDUCTIVE LOOPS - A method of processing an electrical signal includes: capturing, via at least one main lead, an electrical signal; capturing, via at least one noise lead, a noise reference signal, wherein the at least one noise lead includes at least one conductive loop formed on a plane; receiving, by a processing device, the electrical signal and the noise reference signal; and processing, by the processing device, the electrical signal to cancel the noise reference signal from the electrical signal to obtain a processed electrical signal. | 08-29-2013 |
| 20130221965 | B1 Field-Based Regulation Within a Sequence for NMR - A B1 magnetic field may be regulated during a magnetic resonance tomography (MRT) imaging sequence. | 08-29-2013 |
| 20130229180 | Emission of High Frequency Pulses in a Magnetic Resonance Tomography System - A method for emitting a sequence of high frequency pulses that may have different envelopes in a magnetic resonance tomography system is provided. A digital instruction signal that specifies the envelope for the high frequency pulses that are to be emitted is received. A digital control signal is transmitted to a high frequency unit for generating high frequency pulses, depending on the instruction signal. A test signal that allows notification of a current overload situation is received. The current control signal is reduced if the test signal indicates an overload situation. | 09-05-2013 |
| 20130241553 | METHOD OF CHARACTERIZING - The invention relates to a method of characterizing the RF transmit chain of a magnetic resonance imaging scanner ( | 09-19-2013 |
| 20130257430 | Controlling Magnetic Resonance Systems - Methods for controlling magnetic resonance systems having a plurality of high frequency transmission channels through which HF pulse trains are emitted in parallel during operation are described. The methods involves specifying a joint reference pulse train for a plurality of the high frequency transmission channels, and determining a transmission scaling factor for each of the high frequency transmission channels in an HF pulse-optimization method by taking into consideration a specified target magnetization to calculate the HF pulse trains for the transmission channels on the basis of the reference pulse train. During calculation of the transmission scaling factors, a target function is created independently of a target magnetization difference in at least a first optimization mode of the HF pulse-optimization method. The target magnetization difference is considered in the HF pulse-optimization method by way of a boundary condition function instead. Pulse optimization devices and magnetic resonance systems are described. | 10-03-2013 |
| 20130271137 | Magnetic Resonance Trajectory Correcting - Apparatus, methods, and other embodiments associated with magnetic resonance (MR) trajectory correcting using GRAPPA operator gridding (GROG) are described. One example method includes identifying an on angle or regular portion of a projection in an MR trajectory and then computing base GROG weights for that portion. The example method includes identifying a shift direction and a shift amount for the projection. The shift direction is configured to shift the projection towards a desired point in k-space and the shift amount is configured to shift the projection by a desired amount in the shift direction. With a shift direction and amount available, the example method corrects for a gradient delay by manipulating the MR source signal data using the shift direction and the shift amount. In one embodiment, a gradient delay can be determined and used to calibrate an MRI apparatus. | 10-17-2013 |
| 20130271138 | Method for NMR Measurements on Quadrupolar Nuclei - A method is offered which permits NMR measurements of integer spin nuclei to be performed at higher sensitivity than heretofore. In particular, the method enables high-resolution multidimensional correlation NMR measurements on integer spin nucleus S having integer spin S and nucleus I of other spin species. The method starts with applying an RF magnetic field having a frequency that is n times (where n is an integer equal to or greater than 2) the Larmor frequency of the integer spin nucleus S to the spin S. Magnetization transfer is effected between the nucleus I and the integer spin nucleus S. | 10-17-2013 |
| 20130271139 | DETERMINATION OF A CONTROL SEQUENCE FOR A MAGNETIC RESONANCE IMAGING SYSTEM - In a method to determine a control sequence for a magnetic resonance imaging system in order to acquire echo signal-based raw magnetic resonance data in k-space along one or more trajectories on the basis of the control sequence, the control sequence is optimized so that, to control a gradient magnetic field for at least a predetermined portion of the control sequence, a change of an attribute of the gradient magnetic field is limited. The limitation takes place so that a momentary amplitude change rate of the gradient magnetic field falls below a predetermined amplitude change rate limit value, and/or so that a momentary direction change rate of the gradient magnetic field falls below a predetermined direction change rate limit value, and/or so that a momentary gradient change rate of the gradient magnetic field that is based on a combination of the momentary amplitude change rate and the momentary direction change rate falls below a predetermined gradient change rate limit value. | 10-17-2013 |
| 20130285659 | System and Method for Control of RF Circuits for Use With an MRI System - A system and method for automatically adjusting electrical performance of a radio frequency (RF) coil assembly of a magnetic resonance imaging (MRI) system during a medical imaging process of a subject to control changes in loading conditions of the RF coil caused by the subject during the medical imaging process. | 10-31-2013 |
| 20130285660 | Controlling a Magnetic Resonance System - A method for controlling a magnetic resonance system is provided. The magnetic resonance system includes a plurality of radio-frequency transmit channels via which, in operation, parallel RF pulse trains are transmitted. The method includes specifying a common reference pulse train for the plurality of the radio-frequency transmit channels. The method also includes, determining, in an RF pulse optimization method, taking into account a prespecified target magnetization, a transmit scaling factor for each of the radio-frequency transmit channels in order to calculate the RF pulse trains for the transmit channels on the basis of the reference pulse train. The transmit scaling factors are optimized taking into account a component-induced B | 10-31-2013 |
| 20130300417 | SYSTEMS AND METHODS FOR NOISE CONTROL IN A MEDICAL IMAGING SYSTEM - A noise abatement system includes a processor configured to measure noise in an imaging system and generate a switch mode power supply (SMPS) input signal based on the measured noise and an adjustable switched mode power supply configured to receive the SMPS input signal and adjust a switching frequency of the switched mode power supply, based on the SMPS signal, to operate at a frequency that generates harmonics that are outside of an imaging bandwidth of the imaging system. A system and calibration method are also described herein. | 11-14-2013 |
| 20130307538 | MAGNETIC RESONANCE SYSTEM AND METHOD TO CONTINUOUSLY CORRECT PHASE ERRORS OF A MAGNETIC RESONANCE MEASUREMENT SEQUENCE - In a method and magnetic resonance system to correct phase errors in multidimensional, spatially selective radio-frequency excitation pulses in a pulse sequence used to operate the system to acquire magnetic resonance data, a multidimensional, spatially selective radio-frequency excitation pulse is radiated and multiple calibration gradient echoes are acquired. A phase correction and a time correction of the multidimensional, spatially selective radio-frequency excitation pulse is then calculated. | 11-21-2013 |
| 20130307539 | MAGNETIC RESONANCE SYSTEM AND METHOD TO CONTINUOUSLY CORRECT PHASE ERRORS OF A MAGNETIC RESONANCE MEASUREMENT SEQUENCE - In a method and magnetic resonance apparatus to continuously correct phase errors in a magnetic resonance measurement sequence in which multiple sequentially radiated, multidimensional, spatially-selective radio-frequency excitation pulses are used, multiple calibration gradient echoes are acquired in a calibration acquisition sequence and a correction value for a phase response and a correction value for a phase difference are calculated from the multiple calibration gradient echoes. Furthermore, an additional radio-frequency excitation pulse is radiated takes into account the correction values. | 11-21-2013 |
| 20130320980 | PULSE GAP CYCLING FOR IMPROVED SWIFT - A magnetic resonance image is produced by shifting a gap during acquisition of spin data for a specimen. The spin data is generated by a gapped excitation sequence. | 12-05-2013 |
| 20140132266 | MAGNETIC RESONANCE IMAGING APPARATUS AND TRANSMISSION CONTROL METHOD - According to one embodiment, a magnetic resonance imaging apparatus provided with a plurality of transmission channels includes a signal processing unit and a control unit. The signal processing unit acquires a radio frequency magnetic field emitted from each of the plurality of transmission channels through a receiver coil mounted on an object and measure a phase of the radio frequency magnetic field. The control unit determines a phase difference between the plurality of transmission channels based on the phase of the radio frequency magnetic field of each of the plurality of transmission channels measured by the signal processing unit. The control unit controls a phase of a radio frequency pulse inputted to each of the plurality of transmission channels, based on the phase difference. | 05-15-2014 |
| 20140152309 | METHODS OF PREPARING AND OPERATING AN MRI MULTI-CHANNEL COIL - A method of preparing a multi-channel coil, in particular for magnetic resonance imaging (MRI) or for a medical treatment device, wherein the multi-channel coil comprises at least two coil rows being axially arranged along a longitudinal direction (z), wherein each of the at least two coil rows comprises a plurality of coil elements being azimuthally distributed relative to the longitudinal direction (z), comprises the steps of a) electro-magnetic decoupling of the coil rows relative to each other, and b) minimizing a reflected power (P | 06-05-2014 |
| 20140176135 | Multiturn MRI Coils In Combination With Current Mode Class D Amplifiers - Example systems, apparatus, and circuits described herein concern a multi-turn transmit surface coil used in parallel transmission in high field MRI. One example apparatus includes a balun network that produces out-of-phase signals that are amplified to drive current-mode class-D (CMCD) field effect transistors (FETs) that are connected by a coil that includes an LC (inductance-capacitance) leg. The LC leg selectively alters the output analog RF signal and the analog RF signal is used in high field parallel magnetic resonance imaging (MRI) transmission. The multi-turn transmit surface coil produces an improved (e.g., stronger) B1 field without increasing heat dissipation. | 06-26-2014 |
| 20140300359 | RADIO-FREQUENCY COIL ARRAYS AND METHODS OF ARRANGING THE SAME - In accordance with various embodiments, a radio frequency (RF) coil array for use in a magnetic resonance imaging (MRI) system includes at least first and second RF coils. Each of the RF coils have a main body loop configured to at least one of transmit or receive RF energy at an operating imaging frequency in connection with acquiring MRI image data for an MRI system. The RF coil array also includes first and second cables configured to electrically couple the first and second RF coils, respectively, to a system interface. The RF coil array also includes a common ground connection between the first and second cables. The common ground connection is selectively positioned at a grounding point along lengths of the first and second cables to form a ground loop having a select self-resonance frequency (SRF) that differs from the imaging frequency of the MRI system. | 10-09-2014 |
| 20140306708 | Magnetic Resonance Apparatus with Group-by-Group Actuation of Transmission Antennas - A magnetic resonance apparatus including transmission antennas that may be actuated in parallel by a control device of the magnetic resonance apparatus may be operated in a group mode. In the group mode, the transmission antennas are grouped into groups of transmission antennas. The actuation signals of transmission antennas within the respective group are in a respectively predefined relationship relative to one another. A respective group actuation signal for each of the groups of transmission antennas is prescribed for the control device by an operator. The control device carries out checks as to whether a group exposure value established based on the group actuation signals lies below a maximum admissible group exposure limit. If this is the case, the control device establishes the actuation signals for the individual transmission antennas based on the group actuation signals. If this is not the case, the control device carries out another measure. | 10-16-2014 |
| 20150123660 | AUTO-TUNE-AND-MATCH COILS FOR HUMAN WHOLE-BODY IMAGING AND METHOD - A progressive series of five new coils is described. The first coil solves problems of transmit-field inefficiency and inhomogeneity for heart and body imaging, with a close-fitting, 16-channel TEM conformal array design with efficient shield-capacitance decoupling. The second coil progresses directly from the first with automatic tuning and matching, an innovation of huge importance for multi-channel transmit coils. The third coil combines the second, auto-tuned multi-channel transmitter with a 32-channel receiver for best transmit-efficiency, control, receive-sensitivity and parallel-imaging performance. The final two coils extend the innovative technology of the first three coils to multi-nuclear ( | 05-07-2015 |
| 20160077179 | Scan Condition Determining Device, Magnetic Resonance Imaging System, Scan Condition Determining Method, and Program - A scan condition determining apparatus determines scan conditions in a magnetic resonance imaging system. The scan condition determining apparatus includes: a setting unit for setting an imaging range, a desired spatial resolution and a desired SN ratio; and a determining unit for determining a matrix number in a frequency encode direction and a matrix number in a phase encode direction, based on the imaging range and the desired spatial resolution set by the setting unit and determining physical parameters different from the matrix number in a frequency encode direction and a matrix number in a phase encode direction, based on the determined matrix numbers, the set imaging range and the set desired SN ratio. | 03-17-2016 |
| 20160077183 | NUCLEAR MAGNETIC RESONANCE TOOL CALIBRATION - Various embodiments include apparatus and methods to calibrate a nuclear magnetic resonance tool. Example calibration techniques may include using intended ninety degree pulses as a control mechanism to evaluate echo pulses from generating pulse sequences. Example calibration techniques may include comparing a sequence of measurement signals with a reference sequence. Additional apparatus, systems, and methods are disclosed. | 03-17-2016 |
