Described herein are methods for monitoring and/or extracting subject motion from multi-channel electrical coupling in imaging of the subject, in particular in magnetic resonance (MR) imaging of the subject.

Systems and methods for ZTE MRI are disclosed. An exemplary method includes obtaining Larmor frequencies of water and/or fat for a region of interest of a subject to be imaged at a pre-scan and setting a center frequency for an RF transceiver of the MR system at a value between the Larmor frequencies of water and fat. A ZTE pulse sequence is applied to the subject and MR signals in response to the ZTE pulse sequence are received from the subject. The received MR signals are demodulated with the center frequency and an in-phase ZTE image is generated from the demodulated MR signals.

In a method for MRI where k-space describing spatial frequencies in an acquisition volume (AV) is scanned, a first measured data acquisition is performed in the AV with a first gradient field strength of a gradient field, including irradiating a RF pulse into the AV and acquiring a first series of measured values spaced apart temporally, a second measured data acquisition is performed with a second, different gradient field strength, including irradiating a RF pulse into the AV and acquiring a second series of measured values spaced apart temporally. With the first measured data acquisition, the first measured values for a respective response signal are acquired at a first time interval from one another and with the second measured data acquisition, the second measured values for a respective response signal are acquired at a second, different time interval from one another.

A method for the magnetic resonance examination of a measurement object is described, in which a measurement sequence is used in which the magnetic resonance response to the transmitted signal during transmission is measured. It is provided that a correction signal corresponding to the transmitted signal be generated and be used for correction of the response signal. To this end, the correction signal is modulated by a phase value and an amplitude value. The phase value and the amplitude value are automatically and iteratively customized for optimum correction of the response signal by an optimization method using a respective present state value of the measurement signal. Further, a radio-frequency unit (1) is described that can be used to carry out the method according to the invention.

In a method for operating a magnetic resonance (MR) apparatus, MR raw-data is acquired from an acquisition region of a patient for a sampling region of k-space using a MR sequence that employs ultrashort echo times; a first MR image dataset is reconstructed from the MR raw-data of the k-space region; a second MR image dataset is reconstructed from the MR raw-data in a central subregion of the sampling region in k-space; a resolution of the second MR image dataset is interpolated to increase the resolution of the second MR image dataset to a resolution of the first magnetic resonance image dataset; and the first and second MR image datasets are combined to obtain an output MR image dataset.

Described herein are systems, methods, and computer-readable medium for magnetic resonance (MR) based thermometry. In one aspect, in accordance with one embodiment, a method for magnetic resonance based thermometry includes: acquiring, by a variable flip-angle T1 mapping sequence, MR data in an area of interest of a subject that is heated by the application of focused ultrasound (FUS) to the brain of the subject, where the MR data includes T1 values over time, and where the acquisition of the MR data includes applying an accelerated three-dimensional ultra-short spiral acquisition sequence with a nonselective excitation pulse; and determining, based at least in part on a mathematical relationship established by T1 mapping thermometry, a temperature change in the area of interest over time, and where the temperature change is caused at least in part by a change in the applied FUS.

Methods and systems for assessing pulmonary gas exchange and/or alveolar-capillary barrier status include obtaining at least one MRI image and/or image data of .sup.129Xe dissolved in the red blood cells (RBC) in the gas exchange regions of the lungs of a patient. The image is sufficiently sensitive to allow a clinician or image recognition program to assess at least one of pulmonary gas exchange, barrier thickness or barrier function based on the .sup.129Xe MRI RBC image.

A new method is developed for ultrafast, high-resolution magnetic resonance spectroscopic imaging (MRSI) using learned spectral features. The method uses Free Induction Decay (FID) based ultrashort-TE and short-TR acquisition without any solvent suppression pulses to generate the desired spatiospectral encodings. The spectral features for the desired molecules are learned from specifically designed training data by taking into account the resonance structure of each compound generated by quantum mechanical simulations. A union-of-subspaces model that incorporates the learned spectral features is used to effectively separate the unsuppressed water/lipid signals, the metabolite signals, and the macromolecule signals. The unsuppressed water spectroscopic signals in the data can be used for various purposes, e.g., removing the need of additional auxiliary scans for calibration, and for generating high quality quantitative tissue susceptiability mapping etc. Simultaneous spatiospectral reconstructions of water, lipids, metabolite and macromolecule can be obtained using a single .sup.1H-MRSI scan.

Disclosed are methods and systems for ultrashort echo time magnetization transfer (UTE-MT) imaging and signal modeling to quantify the different proton groups, including free water, bound water and macromolecule protons in short T2 tissues such as the menisci, ligaments, tendons and cortical bone. UTE-MT images with a series of MT frequency offsets and MT power are subject to MT modeling to evaluate T1s, T2s, fractions and exchange rates of bound water, free water and macromolecule protons.

A method for generating an image data set of an image area located in a measurement volume of a magnetic resonance system comprising a gradient system and an RF transmission/reception system, comprises the following method steps: reading out k-space corresponding to the imaging area, by: (a) activating a frequency encoding gradient in a predetermined spatial direction and with a predetermined strength G.sub.0 by means of said gradient system, (b) after the activated frequency encoding gradient achieves its strength G.sub.0, radiating a non-slice-selective RF excitation pulse by means of said RF transmission/reception system, (c) after a transmit-receive switch time t.sub.TR following the radiated excitation pulse, acquiring FID signals with said RF transmission/reception system and storing said FID signals as raw data points in k-space along a radial k-space trajectory that is predetermined by the direction and strength G.sub.0 of the frequency encoding gradient, (d) repeating (a) through (c) with respectively different frequency encoding gradient directions in each repetition until k-space corresponding to the image area is read out in an outer region of k-space along radial k-space trajectories, said radial k-space trajectories each having a radially innermost limit k.sub.gap which depends on said switch time t.sub.TR, (e) reading out a remainder of k-space that corresponds to the imaging area, said remainder being an inner region of k-space not being filled by said first region and including at least a center of k-space, in a read out procedure that is different from (a) through (d), and storing all data points read out in (d) and (e); and reconstructing image data from the read out data points ink-space by implementing a reconstruction algorithm; In order to constrain image fidelity and optimize scan duration under given circumstances, the inner k-space region is subdivided into a core region and at least one radially adjacent shell region.