Other

Advanced Mri Technologies, LLC

University of California

Life Services, LLC

Siemens Aktiengesellschaft

New York University

Feinberg, David A.

David A Feinberg

Berthold Kiefer

Scott M Schillak

Matthias Guenther

Kamil Ugurbil

Lawrence E Crooks

John C Hoenninger, Iii

Liyong Chen

Matthias Gunther

Koichi Oshio

Sudhir Ramanna

Suhyung Park

Accelerated GRASE with controlled T2 blurring improves a point spread function (PSF) and temporal signal-to-noise ratio (tSNR) with many slices. The approach seeks to minimize a trade-off between SNR and blurring for functional sensitivity, and uses a new GRASE-optimized random encoding, which takes into accounts for the complex signal decays of T2 and T2* weightings, by achieving incoherent aliasing for constrained reconstruction. Numerical and experimental studies validate the effectiveness of the new method over regular and VFA GRASE (R- and V-GRASE).

Highly accelerated sub-millimeter resolution 3D GRASE with controlled T2 blurring in T2-weighted functional MRI at 7 tesla

A method and apparatus for receiving (RX) radio-frequency (RF) signals suitable for MRI and/or MRS from MRI 'coil loops' (antennae) that are overlapped and/or concentric, and each of which has a preamplifier and frequency-tuning circuitry and an impedance-matching circuitry, but wherein the loops optionally sized differently and/or located at different elevations (distances from the patient's tissue) in order to extract signal from otherwise cross-coupled coil loops and to improve signal-to-noise ratio (SNR) in images made from the received signal.

Method and device for loops-over-loops MRI coils

An MRI method and an MRI system that simultaneously detect blood and/or CSF velocity or flow in plural slices or slabs preferably as not spatially adjacent. Two or more sets of interleaved slices or slabs can be assembled to cover the desired volume and derive higher quality MRI signals and images without a need for a contrast agent, even where the volume is too large for effective flow imaging with known techniques without contrast agent.

Cine phase contrast simultaneous multi-slice and multi-slab imaging of blood flow and cerebrospinal fluid motion

Device and method for loops-over-loops MRI coils

An MRI scanner and an MRI method that effectively reduce the inherent difference in timing of TE in the SIR images by using alternating polarity of the slice selective gradient pulse Gs and corresponding alternate polarity in RF phase offset in the excitation pulse. By using alternating polarity selective gradients, the refocusing gradient pulse on the Gs axis can be eliminated between the excitation pulses so that the time spacing between the multiple SIR excitation pulses is reduced, and therefore the time delay between onset of slice signal decay is reduced. This results in an earlier possible TE of the first excited slice, hence less signal decay and higher SNR, and overall the TE of different slices can be more nearly the same.

MRI using faster multiplexed echo planar imaging (EPI) pulse sequences

An MRI system and method for dynamic susceptibility contrast (DSC) imaging use multiplexed echo planar imaging (M-EPI) to essentially simultaneously acquire MR signals for perfusion parameter images of multiple slices. This essentially simultaneous acquisition of MR signals for multiple slices can be repeated in rapid succession without deteriorating T2* contrast, which makes it practical to image multiple perfusion phases and brings about other significant benefits.

Simultaneous multislice perfusion imaging in MRI

Disclosed are methods and systems for carrying out super-multiplexed magnetic resonance imaging that entwines techniques previously used individually and independently of each other in Simultaneous Echo (or Imaging) Refocusing (SER or SIR) and Multi-Band (MB) excitation, in a single pulse sequence that provides a multiplication rather than summation of desirable effects while suppressing undesirable effects of each of the techniques that previously were used independently.

Multiplicative increase in MRI data acquisition with multi-band RF excitation pulses in a simultaneous image refocusing pulse sequence

Regional arterial spin labeling (regASL) speeds up acquisition without sacrificing the signal-to-noise ratio (SNR) of the resulting perfusion images by using the same control image (i.e. acquired without labeling of blood in a vessel) for two or more vascular territory measurements. This regional ASL is accomplished by creating prepared spin magnetization (e.g. inverted or saturated) in a specific blood vessel, instead of preparing spin magnetization in all feeding blood vessels. As in conventional ASL, two data sets are typically acquired in a downstream position: one with (label image) and one without preparation (control image) in one particular vessel. When regASL is extended to repetitive time series of ASL images to identify perfusion changes for functional MRI (fMRI), the speed of the time series of ASL also is increased because only a single C data set can be used redundantly for all time points of ASL measurement, to reduce the amount of data acquired by nearly one half, with no change in the signal to noise ratio in the ASL images. To account for possible movement of the person causing misregistrations in the time series, the C data can be obtained two or more times throughout the time series while still at lower frequency than in prior techniques with alternating L and C data sets.

Efficient visualization of cortical vascular territories and functional MRI by cycled arterial spin labeling MRI

A process and system acquiring both ultrasound and MRI data from a patient in an MRI scanner and using one to automatically guide or improve the other. The ultrasound data can track the motion of an organ such as a cardiac artery or the diaphragm and the resulting motion information can automatically guide MRI data acquisition to keep the imaging volume at the organ or interest, or can be used to accept or reject MRI data in the process of forming an MRI image, based on whether the organ of interest was within an acceptable range of positions. Conversely, the MRI unit can guide the ultrasound data acquisition so it is properly timed or otherwise controlled in accordance with MRI data acquisition.

Ultrasound within MRI scanners for guidance of MRI pulse sequences

A magnetic resonance imaging (MRI) method of obtaining MRI images of a patient and storing the images in physical storage media.

Arterial spin labeled, segmented, interleaved 3D GRASE MRI

MR imaging produces a projection image showing better image contrast between small blood vessels and background than traditional net intensity projection (NIP) images but more visual clues to vessel depth than traditional maximum intensity projection (MIP) images.

Translucent intensity projection imaging

MRI method and apparatus using simultaneous image refocusing of multiple MRI slices that have different phase histories imparted by applying different amount of additional energy to the different slices before the first refocusing, in combination with applying novel fid spoiling that suppresses interference between stimulated echoes and spin echoes of different slices while allowing non-interfering stimulated echoes to be added to the appropriate primary echoes.

Method and apparatus for removing specific stimulated echoes in simultaneous image refocusing

Multiple signals are excited at different slice positions and then refocused simultaneously. The resulting MRI signals from two or more slices are acquired during a unipolar gradient read period. Then, the signals can be simultaneously refocused in additional unipolar read periods for echo train imaging. In general, signals from multiple slices created by selective RF excitation are read-out on a read gradient.

Simultaneous image refocusing

An MRI method and system in which phase gradients and read gradients overlap over varying time durations. The MRI signals sampled while there is no overlap fill a non-rectangular matrix in K-space. Alternately, the MRI signal is sampled during the times of overlap as well but a zero is placed at the corners of the matrix at locations which correspond to overlap. The benefit include a reduction in the MRI data acquisition time for the same spatial resolution as known sequences, an increase in image spatial resolution for the same MRI data acquisition time as known sequences, lower signal bandwidth and increase the image signal-to-noise ratio (SNR). In addition, in a gradient echo MRI sequence, the read and write gradients do not overlap in time but vary in width (or at least one of the them varies in width) with time to achieve similar advantages.

Time varying read and phase gradients where the duration of their

A plurality of non-overlapping bands is established in k-space. Each band includes a set of lines to be read out between a maximum phase-encoding gradient and a minimum phase-encoding gradient. Similarly, an identical plurality of temporally sequential and non-overlapping subsequences of pulses are established in the MR pulse sequence. Each subsequence corresponds to one and only one of the bands and reads out lines of MR data at phase-encoding gradients that are between the maximum and minimum phase-encoding gradients for that corresponding one. Lines of MR data are read out using the MR pulse sequence and the k-space bands are filled with lines of MR data. Advantageously, the first subsequence is used to fill up the center band in k-space.

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Bodega Bay, CA, United States of America

David A Feinberg