Systems and methods for MR signal synchronization may be provided. The method may include determining a time difference in a local clock generator at a coil side assembly compared to a system clock generator at a system side assembly. The method may include maintaining a constant phase difference between clock signals generated by the local clock generator and by the system clock generator by correcting the local clock generator based on the time difference. The method may include acquiring MR echo signals by scanning at least a part of a subject in response to the clock signal generated by the corrected local clock generator. The method may further include digitizing the MR echo signal at the coil side assembly.

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.

The present disclosure relates to systems and methods for magnetic resonance imaging. The method may include obtaining primary imaging data associated with a region of interest (ROI) of a subject and obtaining secondary data associated with the ROI. The method may also include determining secondary imaging data based on the secondary data by using a trained model. The method may further include reconstructing a magnetic resonance image based on the primary imaging data and the secondary imaging data.

Apparatus and techniques are described herein for nuclear magnetic resonance (MR) projection imaging. Such projection imaging may be used to control radiation therapy delivery to a subject, such as including receiving reference imaging information, generating a two-dimensional (2D) projection image using imaging information obtained via nuclear magnetic resonance (MR) imaging, the 2D projection image corresponding to a specified projection direction, the specified projection direction including a path traversing at least a portion of an imaging subject, determining a change between the generated 2D projection image and the reference imaging information, and controlling delivery of the radiation therapy at least in part using the determined change between the obtained 2D projection image and the reference imaging information.

Apparatus and techniques are described herein for nuclear magnetic resonance (MR) projection imaging. Such projection imaging may be used to control radiation therapy delivery to a subject, such as including receiving reference imaging information, generating a two-dimensional (2D) projection image using imaging information obtained via nuclear magnetic resonance (MR) imaging, the 2D projection image corresponding to a specified projection direction, the specified projection direction including a path traversing at least a portion of an imaging subject, determining a change between the generated 2D projection image and the reference imaging information, and controlling delivery of the radiation therapy at least in part using the determined change between the obtained 2D projection image and the reference imaging information.

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.

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.

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.

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.

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).