G01R33/5673

Through-plane navigator
09846217 · 2017-12-19 · ·

A magnetic resonance scanner (10) includes a main magnet (12), gradient coils (14) and a gradient coil controller (28), one or more RF coils (16,50), an RF transmitter (30), an RF receiver (34), and one or more processors (38). The main magnet (12) generates a B.sub.0 field. The gradient coils (14) and a gradient coil controller (28) generate gradients across the Bo field. The one or more RF coils (16,50) transmit B.sub.1 pulses and receive magnetic resonance signals. The RF transmitter (30) transmits B.sub.1 pulses to the RF coils to excite and manipulate resonance. The RF receiver (34) demodulates received resonance signals into data lines. The one or more processors (38) are connected to the gradient coil controller (28), the RF transmitter (30), and the RF receiver (34) and are programmed to control (70) the RF transmitter and the gradient coil controller to implement an interleaved multi-slice 2D imaging sequence which in each of a plurality of TRs generates a first and second navigation data lines and at least one image data line for each of a plurality of slices. The one or more processors are further programmed to reconstruct (74) the first navigation data lines from the plurality of slices into a first navigation projection image, reconstruct (74) the second navigation data lines from the plurality of slices into a second navigation image; and compare (76) successive navigation projection images to detect and adjust (78) for 3D motion.

SYSTEMS AND METHODS OF DEEP LEARNING FOR LARGE-SCALE DYNAMIC MAGNETIC RESONANCE IMAGE RECONSTRUCTION
20230194640 · 2023-06-22 ·

A method for performing magnetic resonance imaging on a subject comprises obtaining undersampled imaging data, extracting one or more temporal basis functions from the imaging data, extracting one or more preliminary spatial weighting functions from the imaging data, inputting the one or more preliminary spatial weighting functions into a neural network to produce one or more final spatial weighting functions, and multiplying the one or more final spatial weighting functions by the one or more temporal basis functions to generate an image sequence. Each of the temporal basis functions corresponds to at least one time-varying dimension of the subject. Each of the preliminary spatial weighting functions corresponds to a spatially-varying dimension of the subject. Each of the final spatial weighting functions is an artifact-free estimation of the one of the one or more preliminary spatial weighting functions.

IMAGING AN OBJECT SUBJECTED TO A CYCLIC MOTION

For imaging an object subject to a cyclic motion, two or more imaging repetitions are carried out. Each of the imaging repetitions includes a sequence of equally spaced imaging events, wherein each imaging event has an event number, which corresponds to a respective predefined imaging parameter. A cycle duration of the cyclic motion is determined, a number of events per cycle is determined based on the cycle duration and a shift number is determined at least in part randomly. For a first imaging repetition, a starting number is determined depending on the number of events per cycle and the shift number. The first imaging repetition is carried out, wherein the respective sequence is started with an imaging event, whose event number is given by the starting number.

Method and apparatus for capture of physiological signals and image data
09839371 · 2017-12-12 · ·

In a method and an image capturing system (5) for capturing signals and image data of a volume segment of an examination object, raw data of the volume segment are captured, and image time stamps are captured at which certain of the raw data are captured. Physiological signals of the examination object are captured at the same time as capturing the raw data. Signal time stamps are captured at which certain of the physiological signals are captured. The capture of the raw data and the capture of the physiological signals is controlled by the same processor of the image capturing system, so that both the image time stamps and the signal time stamps are predetermined by the same processor.

COIL ASSEMBLY OF MAGNETIC RESONANCE IMAGING DEVICE
20230184864 · 2023-06-15 · ·

The present disclosure relates to a coil assembly of an MRI device. The MRI device may be configured to perform an MR scan on a subject. The coil assembly may include one or more coil units, a substrate, and a sensor mounted within or on the substrate. The one or more coil units may be configured to receive an MR signal from the subject during the MR scan. The substrate may be configured to position the one or more coil units during the MR scan. The one or more coil units may be mounted within or on the substrate. The sensor may be configured to detect a motion signal relating to a physiological motion of the subject before or during the MR scan.

FETAL CARDIAC MRI USING SELF-GATING WITH A CARTESIAN K-SPACE TRAJECTORY

Provided herein are systems and methods for generating fetal cardiac magnetic resonance (MR) images of a living fetus, within a uterus of a parent of the fetus, by imaging the fetus within the uterus using a magnetic resonance imaging (MRI) system. Also provided herein are methods for deriving information indicative of fetal cardiac cycles from MR data obtained by an MRI system while imaging the fetus, the MR data including MR data for the center of k-space. The derived information may be used to differentiate the fetal cardiac cycles from other sources of noise in the MR data such as the parental cardiac cycles.

Noise tolerant localization systems and methods

A system and method for tracking catheter electrode locations with the body of a patient during an MRI scan sequence includes mitigation logic configured to identify one or more impedance measurements that were taken during potentially noise-inducing conditions (i.e., magnet gradients, RF pulses), and were thus subject to corruption by noise. The mitigation logic is configured to replace the potentially corrupt impedance measurements with previously-obtained impedance measurements taken from an immediately preceding acquisition cycle (e.g., from a previous time-slice).

System and method for free-breathing volumetric imaging of cardiac tissue

A magnetic resonance imaging (MRI) system and methods are provided for producing images of a subject. In some aspects, a method includes identifying a point in the cardiac cycle, performing an inversion recovery (IR) pulse at a selected time point from the pre-determined point, and sampling a k-space segment at an inversion time from the IR pulse that is substantially coincident with the pre-determined point. The method also includes repeating the IR pulse and k-space sampling for multiple inversion times, and multiple segments of k-space, in an interleaved manner, to generate datasets having T1-weighted contrasts determined by their respective inversion times. The method further includes reconstructing three-dimensional (3D) spatially-aligned images using the datasets, and generating a T1 recovery map by combining the 3D images. In some aspects, a prospective/retrospective scheme may be used to obtain data fully sampled in the center of k-space and randomly undersampled in the outer regions.

Reduced Field-of-View Perfusion Imaging With High Spatiotemporal Resolution
20170343635 · 2017-11-30 ·

Some aspects of the present disclosure relate a method for magnetic resonance imaging, which can include acquiring, by applying an imaging pulse sequence, magnetic resonance data associated with a region of interest of a subject. The imaging pulse sequence can include a plurality of RF pulses configured to generate a desired image contrast, and an outer-volume suppression (OVS) module to attenuate the signal outside the region of interest. The method can further include reconstructing, from the acquired magnetic resonance data, a plurality of reduced field of view (rFOV) magnetic resonance images corresponding to the region of interest.

Method and system for monitoring a motion of a subject, and corresponding computer program product
11672489 · 2023-06-13 · ·

The disclosure relates to a method for monitoring a motion of a subject, as well as to a corresponding system and computer program product. As part of the method, a monitoring signal is emitted towards a corresponding receiver. The motion of the subject is then detected based on a change in the received monitoring signal. Therein, the monitoring signal is emitted using a spread-spectrum technique and/or using an M-to-N and multi-antenna emitter-receiver system with a set of M transmitting antennas and a set of N receiving antennas.