The invention provides for a medical imaging system (100, 300). The medical imaging system (100, 300) comprises a processor (104). Execution of machine executable instructions (120) causes the processor (104) to: receive magnetic resonance data, wherein the magnetic resonance data comprises B0 field data (122) of a reference scan for a plurality of voxels and water saturation data (124) of a WASSR scan for a subset of voxels of the plurality of voxels, the water saturation data (124) comprising data of a limited number of sample points; determine a local absolute water saturation frequency (130) for each voxel of the subset using the water saturation data (124) of the WASSR scan; and reconstruct a field map (132) comprising a local absolute water saturation frequency for each voxel of the plurality of voxels, wherein the reconstruction comprises determining relative frequency differences between the voxels using the B0 field data (122) of the reference scan and adding a frequency offset to the relative frequency differences based on the determined local absolute water saturation frequencies (130) of the subset.

A system and method are provided for controlling a magnetic resonance imaging (MRI) system. The method includes performing a gradient echo pulse sequence that includes a phase increment of an RF pulse of the gradient echo pulse sequence selected to encode diffusion information into a phase of MR signals. The method also includes controlling the plurality of gradient coils and the RF system to acquire the MR signals as MR data, processing the MR data to determine MR signals corresponding to diffusion in the subject when acquiring the MR signals, and generating at least one of an image or a map of the subject indicating the diffusion in the subject from the MR data.

In a method, an imaging sequence is irradiated into an examination region in which an examination object is located. The imaging sequence includes an acquisition section. The acquisition section includes acquiring a plurality of echo signals, each of which samples a k-space region of a k-space. The plurality of echo signals comprises a plurality of first echo signals and a plurality of second echo signals. The plurality of first echo signals and the plurality of second echo signals are generated from different magnetization configurations. The k-space regions sampled by the plurality of first echo signals sample the k-space in a different order to the k-space regions sampled by the plurality of second echo signals.

Techniques are disclosed relating to the generation of a magnetic resonance (MR) image of a predetermined portion of a volume of an examination object. MR data of the portion may be acquired using echo trains in a first step and in a second step, with each of the echo trains acquiring MR data of a plurality of k-space lines. The plurality of k-space lines extend parallel to one another and perpendicular to a common plane such that per k-space line, one intersection point within a plane results. The MR image is then reconstructed using the acquired MR data.

A method of estimating properties of a resource bearing formation includes receiving, by a processor, a measured echo train generated by a nuclear magnetic resonance (NMR) measurement device deployed in a region of interest, and a measured noise of the measured echo train, and calculating a T.sub.2 distribution subject to a nonlinear equality constraint, the nonlinear equality constraint dependent on the measured noise and a fitting error between the measured echo train and a modeled echo train. Calculating the T.sub.2 distribution includes estimating a solution for the T.sub.2 distribution that is closest to satisfying the nonlinear equality constraint.

Even when imaging is aborted, data collected so far is utilized in image reconstruction, thereby enhancing examination efficiency. A certain priority imaging data available for image reconstruction by a fast-imaging method is determined, when collecting k-space data according to a predetermined imaging method. If collection of the certain priority imaging data is completed when imaging is aborted, imaging reconstruction is executed using the priority imaging data. The priority imaging data is determined based on a relationship between the imaging method under execution, and the fast-imaging method underlying determination of the priority imaging data.

A method for acquiring a magnetic resonance image dataset of an object includes using an imaging protocol in which a number of k-space lines are acquired in one shot. The imaging protocol includes a plurality of shots. A plurality of additional k-space lines are acquired in at least a subset of the shots, such that movement of the object is detected throughout the imaging protocol. A method for generating a motion-corrected magnetic resonance image dataset from the dataset thus acquired, a magnetic resonance imaging apparatus, and a computer program are also provided.

Method for optimizing an MR control sequence for acquiring MR data of an examination subject by means of an MR device having gradient coils. The method includes providing an MR control sequence having sequence portions, each having an excitation portion, a phase encoding portion and a readout portion, wherein the phase encoding portion is arranged in each case between the excitation portion and the readout portion with respect to time; providing a defined parameter for the MR control sequence; providing an optimization objective; ascertaining usage time of the gradient coils between the excitation portion and the readout portion with respect to time for each of the sequence portions; optimizing the excitation portions for each of the sequence portions considering the ascertained usage time for the corresponding sequence portion and the defined parameter with regard to the optimization objective; and providing the optimized MR control sequence having the optimized excitation portions.

The invention provides a method for performing a magnetic resonance measurement of an element in a target region, wherein the element has a magnetic resonance excitation spectrum peak with a linewidth L.sub.R, wherein the method comprises a measurement cycle (100) comprising: a magnetization transfer stage (110) comprising providing a plurality of pulses (115) of first radiation to the target region, wherein the plurality of pulses (115) are selected to provide a net pulse having a net pulse angle α.sub.N≤1°, and wherein the first radiation comprises a first frequency spectrum peak having a first linewidth L.sub.F, wherein the first frequency spectrum peak at least partially overlaps with the magnetic resonance excitation spectrum peak, and wherein L.sub.F>5*L.sub.R; an excitation stage (130) comprising providing a radio frequency pulse to the target region, wherein the radio frequency pulse excites the element resulting in a transverse magnetization of the element; and a measurement stage (140) comprising detecting a signal from the element, wherein the measurement stage (140) is temporally arranged at an echo time TE after the radio frequency pulse, wherein the echo time TE is smaller than a transverse relaxation time of the element in the target region.

A method for magnetic resonance imaging (MRI) may include cause, based on a pulse sequence, a magnetic resonance (MR) scanner to perform a scan on an object. The pulse sequence may include a steady-state sequence and an acquisition sequence that is different from the steady-state sequence. The steady-state sequence may correspond to a steady-state phase of the scan in which no MR data is acquired. The acquisition sequence may correspond to an acquisition phase of the scan in which MR data of the object is acquired. The method may also include generating one or more images of the object based on the MR data.