Patent application number | Description | Published |
20130249549 | DETERMINATION OF A MAGNETIC RESONANCE SYSTEM CONTROL SEQUENCE - In method and a control sequence determination device to determine a magnetic resonance system control sequence that includes at least one radio-frequency pulse train to be emitted by a magnetic resonance system, a target magnetization (m) is initially detected, and an energy distribution function in k-space is determined on the basis of the target magnetization. A k-space trajectory is then determined under consideration of the energy distribution function in k-space, for which the radio-frequency pulse train is then determined in an RF pulse optimization method. The method is suitable for operation of a magnetic resonance system, and a magnetic resonance system includes such a control sequence determination device. | 09-26-2013 |
20150070011 | METHOD AND MAGNETIC RESONANCE APPARATUS TO GENERATE A SPATIALLY SELECTIVE EXCITATION - In a method to generate a spatially selective excitation in an imaging region of a magnetic resonance apparatus that precedes an acquisition of magnetic resonance data, in the course of the excitation an excitation trajectory in k-space is traversed, the excitation trajectory having a symmetry relative to the k-space center in at least one direction of k-space in the sense that a first traversed extreme value in this direction corresponds to the negative of the other extreme value traversed in this direction, so the excitation trajectory is shortened in the at least one directions on one side of the zero point between the extreme values, and the shortened excitation trajectory is used for excitation. | 03-12-2015 |
20150108984 | METHOD AND APPARATUS FOR DETERMINATION OF A MAGNETIC RESONANCE SYSTEM CONTROL SEQUENCE - In a method and a control sequence determination device for determining a magnetic resonance system control sequence includes at least one radio-frequency pulse train to be emitted by a magnetic resonance system, a target magnetization is acquired and a k-space trajectory is determined. A radio-frequency pulse train for the k-space trajectory is then determined in an RF pulse optimization method using a target function, wherein the target function includes a combination of different trajectory curve functions, of which at least one trajectory curve function is based on a trajectory error model. A method for operating a magnetic resonance system uses such a control sequence and a magnetic resonance system has such a control sequence determination device. | 04-23-2015 |
Patent application number | Description | Published |
20150204955 | METHOD AND MAGNETIC RESONANCE APPARATUS FOR CORRECTION OF A B0 MAP FOR CHEMICAL SHIFTS - In a method for correction of a B0 field map measured with a magnetic resonance device, that describes deviations from a nominal field strength in the homogeneity area of the magnetic resonance device by deviations from a nominal frequency for protons bonded to water, the deviations being represented as Larmor frequency values for different picture elements shifted by chemical shifts, the B0 field map is recorded with spins of the fat and water protons not in phase. The B0 field map is segmented by evaluating the differences of the Larmor frequency values of adjacent picture elements of the B0 field map in at least two contiguous clusters. For each cluster, a decision is made on the basis of a smoothness criterion and a compactness criterion as to whether a cluster containing a majority of protons bonded into fat is involved. Clusters identified as containing a majority of protons bonded into fat are corrected by lowering the Larmor frequency values by the difference between the nominal frequency for protons bonded into water and the corresponding nominal frequency for protons bonded to fat. | 07-23-2015 |
20150234025 | METHOD AND MAGNETIC RESONANCE APPARATUS FOR DETERMINATION OF RADIO-FREQUENCY PULSES - In a method and magnetic resonance apparatus for determination of radio-frequency pulses, a time-parallel transmission of a radio-frequency pulse influences the transverse magnetization of an object under examination in a specified spatial region. The spatial region is depicted as a vector and approximated by decomposition into a finite number of weighted basis functions of the decomposition. As a result, the length of the approximated vector is less than the length of the original vector. The radio-frequency pulse is determined as a function of the approximated vector. This method can be used to determine a multichannel RF pulse. | 08-20-2015 |
20150285877 | Magnetic resonance imaging method for at least two separate radio-frequency transmit coils with time-delayed slice-selective excitation pulses - A method for creating an image data set using a magnetic resonance system including at least two RF transmit coils includes, for each RF transmit coil, calculating a value for a susceptibility magnetic field gradient to be corrected from the G | 10-08-2015 |