A method for high spatial and temporal resolution dynamic contrast enhanced magnetic resonance imaging using a random subsampled Cartesian k-space using a Poisson-disk random pattern acquisition strategy and a compressed sensing reconstruction algorithm incorporating magnitude image subtraction is presented. One reconstruction uses a split-Bregman minimization of the sum of the L1 norm of the pixel-wise magnitude difference between two successive temporal frames, a fidelity term and a total variation (TV) sparsity term.

A magnetic resonance imaging system can include a basic field magnetic arrangement for generating a main magnetic field and a number of spatially separated imaging regions, the basic field magnetic arrangement including several spatially separated magnet segments, in order to generate segment magnetic fields with a defined segment field direction, at least two of the spatially separated magnet segments being configured in a way that their defined segment field directions are running in an angular fashion to each other so that the segment magnetic fields result in a main magnetic field which has the form of toroid, where the magnetic resonance imaging system is designed to be adapted to MR imaging of dedicated body or organ parts of a patient.

Systems and methods for planning peripheral endovascular, and other, procedures based on magnetic resonance imaging (“MRI”] are provided. Mechanical properties of lesions, morphology, and vessel patency are characterized based on non-contrast angiography and ultrashort echo time (“UTE”] images. The methods described in the present disclosure also provide improved visualization of the vascular tree and microchannels.

The invention relates to a method of Dixon-type MR imaging. It is an object of the invention to provide a method that enables efficient and reliable water/fat separation using bipolar readout magnetic field gradients and avoids flow-induced leaking and swapping artifacts. According to the invention, an object (10) is subjected to an imaging sequence, which comprises at least one excitation RF pulse and switched magnetic field gradients, wherein two echo signals, a first echo signal and a second echo signal, are generated at different echo times (TE1, TE2). The echo signals are acquired from the object (10) using bipolar readout magnetic field gradients. A first single echo image is reconstructed from the first echo signals and a second single echo image is reconstructed from the second echo signals. A zero echo time image is computed by extrapolating the phase of the first single echo image at each voxel position to a zero echo time using the phase difference between the first and the second single echo image at the respective voxel position. Flow-induced phase errors are identified and estimated in the zero echo time image, and the phase of the first single echo image is corrected according to the estimated flow-induced phase errors. Finally, a water image and/or a fat image are reconstructed from the echo signals, wherein signal contributions from water and fat to the echo signals are separated using the phase-corrected first single echo image and the second single echo image. Moreover, the invention relates to a MR device (1) and to a computer program to be run on a MR device (1).

A system and method is provided for acquiring flow encoded data from a subject using a magnetic resonance imaging (MRI) system. The method includes acquiring flow encoded (FE) data with alternating encoding polarities and along two of three orthogonal directions through the subject over at least two cycles of the flow within the subject; and separating the FE data into directional FE datasets using a temporal filter that separates the FE data based on temporal modulation of the FE directions caused by the alternating encoding polarities extending over the at least two cycles of the flow within the subject that shift the Fourier spectrum of velocity waveforms corresponding to the FE data. The method also includes using the directional FE datasets to generate an image of the subject showing flow within the subject caused by the at least two cycles of flow within the subject.

A method and apparatus produce angiographic magnetic resonance (MR) images that are based on unsaturated spins flowing into an imaging volume, wherein vessels of the person under examination that do not run parallel to a coordinate axis of the MR apparatus are imaged. The nuclear magnetization in at least a first imaging slice of the person under examination is excited in order to generate MR signals in at least one imaging slice, and MR signals from the at least one first imaging slice are received in order to produce angiographic MR images of the vessels. The at least imaging slice has a curved slice profile.

The systems and methods of the present disclosure address the problem of up-sampling an insufficiently sampled signal of numbers or images that does not yield interpretable data. A computing device may acquire from a sensor, a reference signal and a quasi-periodic signal of a subject over a predefined time period. The reference signal may have a fixed sampling rate. The quasi-periodic signal may have a variable sampling rate. The computing device may filter, using a band-pass filter, the reference signal to obtain a monocomponent signal. The computing device may determine, by applying a Hilbert transform on the monocomponent signal, an analytic phase. The computing device may generate a phase projected signal from the quasi-periodic signal based on the analytic phase. The phase projected signal may have a plurality of data points of the quasi-periodic signal across the predefined time period mapped to a predefined phase interval.

Devices, systems, and methods for visually depicting a vessel and evaluating a physiological condition of the vessel are disclosed. One embodiment includes obtaining, at a first time, a first image of the vessel, the image being in a first medical modality, and obtaining, at a second time subsequent to the first time, a second image of the vessel, the image being in the first medical modality. The method also includes spatially co-registering the first and second images and outputting a visual representation of the co-registered first and second images on a display. Further, the method includes determining a physiological difference between the vessel at the first time and the vessel at the second time based on the co-registered first and second images, and evaluating the physiological condition of the vessel of the patient based on the determined physiological difference.

A method for determining a signature index of an observed tissue comprises the step of providing a generic attenuation model of a motion-probing gradient pulse MRI attenuated signal S(b), and providing a reference model parameter vector (p.sub.R(i)) corresponding to a reference state of the tissue. On the basis of the evolution of the determined partial differential sensitivities dS.sub.i(b) of the model attenuated signal S(b) to each model parameter p(i) at the neutral state attenuated signal S.sub.N(b) versus b values, a discrete and narrow size set of key b is built and a series of MRI images of the observed tissue are acquired by using the key b values. Then, for each voxel a signature index (sADC(V), Sdist(V), SCdist(V), Snl(V), SI(V)) of the voxel V is determined as a scalar function depending on a distance between the voxel signal pattern acquired at the key b values and the signal pattern of the reference state of the tissue at the same key b values. An apparatus is configured for implementing such a method.

Method for susceptibility weighted magnetic resonance imaging of vasculature, the method comprising the following steps: acquiring multi-echo data containing a time-of-flight signal in at least the first echo (S1); identifying voxels belonging to arteries from the data (S2); andgenerating corresponding information on artery presence (S3); The invention further relates to a corresponding system (10) for susceptibility weighted magnetic resonance imaging of vasculature.