A magnetic resonance imaging apparatus according to an embodiment includes a processor and a memory. The memory stores processor-executable instructions that, when executed by the processor, cause the processor to receive an operation of setting an application condition concerning a local excitation pulse that is a radio frequency (RF) pulse for local excitation applied to a local region different from an imaging region; generate a waveform of the local excitation pulse based on the application condition; and set an imaging condition such that an index value calculated from the waveform of the local excitation pulse does not exceed a limit value.

A method for recording a magnetic resonance image data set includes providing a magnetic resonance sequence. The magnetic resonance sequence includes at least one radio-frequency pulse and a slice-selection gradient pulse applied during or before the radio-frequency pulse, which is configured as non-constant. The method includes providing at least one correction term for compensating a magnetic field change of the slice-selection gradient pulse. The magnetic field change is ascertained via a transfer characteristic of the gradient system of the magnetic resonance system. The method also includes recording at least one magnetic resonance image data set with the magnetic resonance sequence using the correction term.

A magnetic resonance imaging apparatus according to an embodiment includes a specifying unit and an acquiring unit. The specifying unit specifies, on a basis of a detection result of target sites of a subject detected from an image on which the target sites are visualized, a first region and a second region which is different from the first region on the image. The acquiring unit acquires data of the second region by using an imaging condition which is different from an imaging condition on an imaging slice and used for acquiring data of the first region.

The present invention provides a method and apparatus for generating a specific flip angle distribution in magnetic resonance imaging; the method uses a plurality of RF transmission coils combined with linear and nonlinear spatial encoding magnetic fields to generate a homogeneous flip angle distribution.

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.

In a method and magnetic resonance (MR) apparatus for recording MR signals in a recording volume of an examination object with an imaging sequence, the recording volume has a first recording region in which at least one system component of the scanner of the MR apparatus has a first homogeneity, which is greater than a homogeneity of the at least one scanner component in a second recording region of the recording volume. A magnetization of nuclear spins in the recording volume is produced by at least one RF pulse, with the RF pulse being determined such that the magnetization produced in the first recording region by the at least one RF pulse is greater than magnetization produced in the second recording region by the at least one RF pulse.

An IR pulse is applied to a tag region B that is disposed at the upstream side of the ascending aorta relative to a tag region A at a timing with a second predetermined delay time TD2 (for example, 600 ms) from the application time of an IR pulse to the tag region A to thereby perform tagging. By this tagging, it is possible to suppress the MR signals derived from the substantial portions and the blood within the tag region B. Subsequently, an imaging scan is performed after a predetermined time lapse TIA (for example, 1200 ms) from the application time of the IR pulse to the tag region A or after a predetermined time lapse TIB (for example, 600 ms) from the application time of the IR pulse to the tag region B.

Starting with a magnetic resonance imaging system control sequence that has a radio-frequency (RF) pulse train to control the RF transmission system and a gradient pulse train, chronologically matching the RF pulse train, to control the gradient system, the gradient pulse train including a predetermined selection gradient pulse chronologically matched to a refocusing pulse of the RF pulse train, the execution capability of the control sequence is initially established using an execution capability criterion, in particular under consideration of a refocusing flip angle of the refocusing pulse. Modification of the refocusing pulse and/or of the selection gradient pulse takes place depending on the establishment of the execution capability of the control sequence.

In a method and a magnetic resonance system to acquire MR data of a slice of a volume segment within an examination subject, a slice selection gradient is activated along a first direction that is orthogonal to the slice. An RF excitation pulse is radiated for selective excitation of the slice, a first phase coding gradient is activated along the first direction, and a second phase coding gradient is activated along a second direction. The second direction is orthogonal to the first direction. A readout gradient is activated along a third direction that is orthogonal to the first direction and the second direction. MR data are acquired while the readout gradient is activated. A number of phase coding steps for the second phase coding gradient is determined depending on the first phase coding gradient.

The present invention provides a magnetic resonance imaging system for imaging a subject by a multi-shot imaging. The magnetic resonance imaging system comprises an acquiring unit for acquiring MR raw data corresponding to a plurality of shots; an imaging unit for generating a plurality of folded images from the MR raw data, wherein each of the plurality of folded images is generated from a subset of the MR raw data; a deriving unit for deriving magnitude of each pixel of each folded image; a detecting unit for detecting a motion of the subject during the multi-shot imaging based on similarity measurements of any two folded images of the plurality of folded images, wherein the detecting unit further comprises a first deriving unit configured to derive the measured similarities; and a reconstructing unit for reconstructing a MR image of the subject based on MR raw data obtained according to a detection result of the detecting unit. Since the partially acquired MR raw data is used for motion detection directly, it would be more rapid and stable.