G01R33/56509

Motion estimation and correction in magnetic resonance imaging

A method of medical imaging including receiving k-space data that is divided into multiple k-space data groups, selecting one of the multiple k-space data groups as a reference k-space data group, and calculating spatial transform data for each of the multiple k-space data groups by inputting the multiple k-space data groups and the reference k-space data group into a transformation estimation module. The spatial transformation estimation module is configured for outputting spatial transform data descriptive of a spatial transform between a reference k-space data group and multiple k-space data groups in response to receiving the reference k-space data group and the multiple k-space data groups as input. The method further comprises reconstructing a corrected magnetic resonance image according to the magnetic resonance imaging protocol using the multiple k-space data groups and the spatial transform data for each of the multiple k-space data groups.

METHOD FOR CONTROLLING A MEDICAL IMAGING EXAMINATION OF A SUBJECT, MEDICAL IMAGING SYSTEM AND COMPUTER-READABLE DATA STORAGE MEDIUM

The method comprises receiving an image sequence of the subject from the camera during the medical imaging scan; receiving at least one of the current position or velocity of the patient table during the medical imaging scan; performing a motion tracking analysis of the image sequence to extract a motion model, wherein at least one of the motion tracking analysis or the motion model is tailored to the body region of interest and takes into account the at least one of the current patient table position or velocity; and analysing the motion model to detect subject motion and, if the detected motion is above a threshold, at least one of adapting the medical imaging examination or issuing an alert.

Coil assembly of magnetic resonance imaging device

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.

MOTION CORRECTED TRACER-KINETIC MAPPING USING MRI
20220373631 · 2022-11-24 ·

Disclosed herein is a medical system (100, 300, 500) comprising a memory (110) storing machine executable instructions (120) and a magnetic resonance reconstruction module (122). The magnetic resonance reconstruction module is configured to reconstruct a motion corrected tracer-kinetic map (126) from measured k-space data (124). The measured k-space data is undersampled. The measured k-space data is T1 weighted. The measured k-space data is dynamic contrast enhanced k-space data. The medical system further comprises a processor (104) configured for controlling the medical system. Execution of the machine executable instructions causes the processor to: receive (200) the measured k-space data; and reconstruct (202) the motion corrected tracer-kinetic map by inputting the measured k-space data into the magnetic resonance reconstruction module. The magnetic resonance reconstruction module (122) is configured to reconstruct the motion corrected tracer-kinetic map as a direct model-based reconstruction from the measured k-space data (124).

METHODS AND SYSTEMS FOR SPIN-ECHO TRAIN IMAGING USING SPIRAL RINGS WITH RETRACED TRAJECTORIES

Methods, computing devices, and magnetic resonance imaging systems that improve image quality in turbo spiral echo (TSE) imaging are disclosed. With this technology, a TSE pulse sequence is generated that includes a series of radio frequency (RF) refocusing pulses to produce a corresponding series of nuclear magnetic resonance (NMR) spin echo signals. A gradient waveform including a plurality of segments is generated. The plurality of segments collectively comprise a spiral ring retraced in-out trajectory. During an interval adjacent to each of the series of RF refocusing pulses, a first gradient pulse is generated according to the gradient waveform. The first gradient pulses encode the NMR spin echo signals. An image is then constructed from digitized samples of the NMR spin echo signals obtained based at least in part on the encoding.

MOTION COMPENSATION FOR MRI IMAGING

Training a neural network to correct motion-induced artifacts in magnetic resonance images includes acquiring motion-free magnetic resonance image (MRI) data of a target object and applying a spatial transformation matrix to the motion-free MRI data. Multiple frames of MRI data are produced having respective motion states. A Non-uniform Fast Fourier Transform (NUFFT) can be applied to generate respective k-space data sets corresponding to each of the multiple frames of MRI; the respective k-space data sets can be combined to produce a motion-corrupted k-space data set and an adjoint NUFFT can be applied to the motion-corrupted k-space data set. Updated frames of motion-corrupted MRI data can be formed. Using the updated frames of motion corrupted MRI data, a neural network can be trained that generates output frames of motion free MRI data; and the neural network can be saved.

Apparatus and method for motion tracking in brain imaging

Disclosed is apparatus and method for motion tracking of a subject in medical brain imaging. The method comprises providing a light projector and a first camera; projecting a first pattern sequence (S1) onto a surface region of the subject with the light projector, wherein the subject is positioned in a scanner borehole of a medical scanner, the first pattern sequence comprising a first primary pattern (P.sub.1,1) and/or a first secondary pattern (P.sub.1,2); detecting the projected first pattern sequence (S1′) with the first camera; determining a second pattern sequence (S2) comprising a second primary pattern (P.sub.2,1) based on the detected first pattern sequence (S1′); projecting the second pattern sequence (S2) onto a surface region of the subject with the light projector; detecting the projected second pattern sequence (S2′) with the first camera; and determining motion tracking parameters based on the detected second pattern sequence (S2′).

APPARATUS FOR MONITORING OF A PATIENT UNDERGOING A MAGNETIC RESONANCE IMAGE SCAN

The present invention relates to an apparatus (10a) for monitoring of a patient undergoing a Magnetic Resonance Image (MRI) scan. The apparatus comprises an input unit (20a), a processing unit (30a), and an output unit (40a). The input unit is configured to provide the processing unit with at least one sensor data of a patient undergoing an MRI scan by an MRI scanner. The input unit is configured to provide the processing unit with at least one scan parameter of the MRI scanner for the MRI scan. The input unit is configured to provide the processing unit with at least one characteristic of the patient. The processing unit is configured to predict a stress level of the patient and/or a predicted motion state of the patient, the prediction or predictions comprising utilization of the at least one sensor data of the patient, the at least one scan parameter of the MRI scanner, and the at least one characteristic of the patient. The output unit is configured to output information relating to the predicted stress level of the patient and/or the predicted motion state of the patient.

METHOD AND SYSTEM FOR DETECTING MOVEMENT OF AT LEAST ONE PART OF A SUBJECT
20220361822 · 2022-11-17 ·

Movement detection of at least one part of a subject located inside a magnetic resonance imaging (MRI) device is provided. A method includes performing an MR scan by executing a programmable MR sequence protocol. The sequence protocol includes MR excitation pulses to be transmitted via a parallel transmit system and receive time windows for receiving magnetic resonance signals via a receive system. The MR sequence protocol includes, in between the MR excitation pulses, the generation of multi-channel pilot tone signals that are transmitted via the parallel transmit system and an RF transmit coil array. During transmission of the multi-channel pilot tone signals, the pilot tone signals are received with an RF receive coil array. The received pilot tone signals are forwarded via the receive system to an analyzing unit, and movement of at least one part of the subject is determined by analyzing the received pilot tone signal.

MRI APPARATUS AND MRI METHOD

According to one embodiment, MRI apparatus includes processing circuitry and an imaging device. The processing circuitry is configured to acquire at least one of body size information relating to a size of an object and breath-hold information relating to a breath-holdable time of the object. The processing circuitry is further configured to determine an imaging condition to be performed on the object based on the at least one of the body size information and the breath-hold information. The imaging device performs imaging of the object in accordance with the determined imaging condition.