Abstract: The invention relates to a method of MR imaging of an object positioned in an examination volume of a MR device (1). It is an object of the invention to enable efficient silent ZTE imaging with self-refocusing. The method of the invention comprises the steps of:—specification of a set of radial k-space spokes to cover a spherical k-space volume;—selection of subsets of a predetermined number of spokes from the specified set so that the concatenation of the spokes contained in each of the subsets forms a closed trajectory in k-space, wherein the selection of the subsets involves optimizing a cost function;—subjecting the object (10) to a zero echo time imaging sequence, wherein each of the subsets of spokes is acquired as a sequence of gradient echo signals; and—reconstructing an MR image from the acquired spokes. Moreover, the invention relates to a MR device and to a computer program for a MR device.

Abstract: Disclosed herein is a medical system (100, 300) comprising a memory (110) storing machine executable instructions (120) and an MRF scoring module (122). The MRF scoring module is configured for outputting an MRF quality score (126) in response to receiving MRF data (124) as input. The medical system further comprises a computational system (106) configured for controlling the medical system, wherein execution of the machine executable instructions causes the computational system to: receive (200) the MRF data; receive (202) the MRF quality score in response to inputting the MRF data into an MRF scoring module; append (206) the MRF quality score to the MRF data if the MRF quality score is within a predetermined range (128); and provide (208) a signal (132) if the MRF quality score is outside of the predetermined range.

Abstract: The invention relates to a method of MR imaging. It is an object of the invention to provide an improved B1 mapping method that is less affected by T1 relaxation. The invention proposes that a first stimulated echo imaging sequence (25) is generated comprising at least two preparation RF pulses (?) radiated during a first preparation period (21) and a sequence of reading RF pulses (?) radiated during a first acquisition period (22) temporally subsequent to the first preparation period (21). A first set of FID signals (IFID) and a first set of stimulated echo signals (ISTE) are acquired during the first acquisition period (22). A second stimulated echo imaging sequence (27) is generated comprising again at least two preparation RF pulses (?) radiated during a second preparation period (21) and a sequence of reading RF pulses (?) radiated during a second acquisition period (22) temporally subsequent to the second preparation period (21).

Abstract: Abstract: Disclosed herein is a medical system comprising a memory (110) storing machine executable instructions (120) and a trained neural network (122). The trained neural network is configured to output corrected magnetic resonance image data (130) in response to receiving as input a set of magnetic resonance images (126) each having a different spatially constant frequency off-resonance factor.

Abstract: Disclosed herein is a method of training a neural network (214) to perform a SENSE magnetic resonance imaging reconstruction. The method comprises receiving (100) initial training data, wherein the initial training data comprises sets of initial training complex channel images each paired with a predetermined number of initial ground truth images. The method further comprises generating (102) additional training data by performing data augmentation on the initial training data such that the data augmentation comprises adding a distinct phase offset to each of the set of initial training complex channel images during generation of the sets of additional training complex channel images. The method further comprises inputting (104) the sets of additional training complex channel images into the neural network and receiving in response a predetermined number of output training images and performing deep learning using the output training images.

Abstract: The invention relates to a method of MR imaging of an object positioned in an examination volume of a MR device (1). It is an object of the invention to enable efficient silent ZTE imaging with self-refocusing. The method of the invention comprises the steps of:—specification of a set of radial k-space spokes to cover a spherical k-space volume;—selection of subsets of a predetermined number of spokes from the specified set so that the concatenation of the spokes contained in each of the subsets forms a closed trajectory in k-space, wherein the selection of the subsets involves optimizing a cost function;—subjecting the object (10) to a zero echo time imaging sequence, wherein each of the subsets of spokes is acquired as a sequence of gradient echo signals; and—reconstructing an MR image from the acquired spokes. Moreover, the invention relates to a MR device and to a computer program for a MR device.

Abstract: A magnetic resonance imaging system includes a gradient system and a processor for controlling the magnetic resonance imaging system.

Abstract: The invention provides for a magnetic resonance imaging system (100) for acquiring magnetic resonance data (142) from a subject (118) within an imaging zone (108). The magnetic resonance imaging system comprises a memory (134, 136) for storing machine executable instructions (160), and pulse sequence commands (140, 400, 502, 600, 700), wherein the pulse sequence commands are configured to cause the magnetic imaging resonance system to acquire the magnetic resonance data according to a magnetic resonance fingerprinting technique. The pulse sequence commands are further configured to control the magnetic resonance imaging system to perform spatial encoding using a zero echo time magnetic resonance imaging protocol.

Abstract: The invention relates to a method of MR imaging of an object (10). The problem of the invention is to provide an improved MR imaging technique that enables fast and robust determination of spatial sensitivity profiles of RF receiving antennas (11, 12, 13) used in parallel imaging as well as B1 and/or B0 mapping. The method of the invention comprises subjecting the object (10) to a stimulated echo sequence. Two or more stimulated echo signals (STE, STE*) are acquired, namely a direct stimulated echo signal (STE) and a conjugated stimulated echo signal (STE*), wherein at least one of the stimulated echo signals (STE, STE*) is received in parallel via an array of two or more RF receiving antennas (11, 12, 13) having different spatial sensitivity profiles, and wherein at least another one of the stimulated echo signals (STE, STE*) is received via a body RF coil (9) having an essentially homogeneous spatial sensitivity profile.

Abstract: The invention provides for a medical instrument (100, 500) comprising a magnetic resonance imaging system (102) for acquiring magnetic resonance data (142) from a subject (118) within an imaging zone (108). The magnetic resonance imaging system comprises: a main magnet (104) for generating a B0 magnetic field within the imaging zone; a memory (134, 136) containing machine executable instructions (160, 162, 164, 166) and pulse sequence commands (140); a processor (130) for controlling the medical instrument.

Abstract: The invention relates to a magnetic resonance imaging system (100). The magnetic resonance imaging system (100) comprises a gradient system and a processor (124) for controlling the magnetic resonance imaging system (100). Execution of machine executable instructions causes the magnetic resonance imaging system (100) to: acquire by coil elements (114) first magnetic resonance data simultaneously from a group of passive local probes 5 (302, 312, 402, 702, 901), wherein the first group of passive local probes (302, 312, 402, 702, 901) comprises a plurality of passive local probes (302, 312, 402, 702, 901) located spaced apart from each other; disentangle contributions to the first magnetic resonance data from the individual local probes, calculate for the magnetic resonance imaging system (100) a gradient impulse response function of the gradient system using the first magnetic resonance data 10 from the local probes; determine correction factors using the gradient impulse response function.

Abstract: A target treatment apparatus for treating a target region (130) within a subject (140) is provided. The apparatus includes an MRI apparatus (100) for generating MR images during an MR scan of the subject disposed within an examination region (110). The apparatus further includes an MRI localizer (150) for receiving the image data from the MRI apparatus wherein the target (130) is localized and a reference marker localizer (160, 160?) for non-invasively receiving reference data from a plurality of reference points disposed in proximity to the target wherein the reference points are localized. A tracking processor (300) is also included in the apparatus for receiving localized data from the MRI localizer wherein a relationship between the reference markers and the target region is generated.

Abstract: The invention provides for a magnetic resonance imaging system (100) for acquiring magnetic resonance data (142) from a subject (118) within an imaging zone (108). The magnetic resonance imaging system comprises a memory (134, 136) for storing machine executable instructions (160), and pulse sequence commands (140, 400, 502, 600, 700), wherein the pulse sequence commands are configured to cause the magnetic imaging resonance system to acquire the magnetic resonance data according to a magnetic resonance fingerprinting technique. The pulse sequence commands are further configured to control the magnetic resonance imaging system to perform spatial encoding using a zero echo time magnetic resonance imaging protocol.

Abstract: The invention relates to a method of MR imaging of an object (10) placed in the examination volume of a MR device (1). It is the object of the invention to provide an improved MR-based temperature mapping method.

Abstract: A method of MR imaging, wherein a portion of a body placed in the examination volume of a MR device is subjected to an imaging sequence of RF pulses and switched magnetic field gradients. The imaging sequence is a stimulated echo sequence including i) at least two preparation RF pulses (?) radiated toward the portion of the body during a preparation period, and ii) one or more reading RF pulses (?) radiated toward the portion of the body during an acquisition period temporally subsequent to the preparation period. One or more FID signals and one or more stimulated echo signals are acquired during the acquisition period. A B1 map indicating the spatial distribution of the RF field of the RF pulses within the portion of the body is derived from the acquired FID and stimulated echo signals.

Abstract: A parallel magnetic resonance imaging system (1) includes at least one radio frequency (RF) coil (10, 12) with a plurality of coil elements, a smart select unit (24), a parallel imaging parameter unit (28), and a sequence control (16). The smart select unit (24), from a pre-scan or prior scan of a subject with the at least one RF coil, constructs (60) a signal map and a plurality of noise maps based on different sets of reduction factors. The parallel imaging parameter unit (28) selects a set of reduction factors corresponding to a noise map which includes a highest signal-to-noise ratio (SNR). The sequence control (16) performs a magnetic resonance imaging scan of the subject based on the selected reduction factors.

Abstract: The invention relates to a method of MR imaging of an object (10) placed in an examination volume of a MR device (1). The method comprises the steps of: —subjecting the object (10) to an imaging sequence comprising phase-modulated multi-slice RF pulses for simultaneously exciting two or more spatially separate image slices, —acquiring MR signals, wherein the MR signals are received in parallel via a set of at least two RF coils (11, 12, 13) having different spatial sensitivity profiles within the examination volume, and —reconstructing a MR image for each image slice from the acquired MR signals, wherein MR signal contributions from the different image slices are separated on the basis of the spatial sensitivity profiles of the at least two RF coils (11, 12, 13) and on the basis of the phase modulation scheme of the RF pulses.

Abstract: The present invention provides a phantom (200) for use in a magnetic resonance (MR) imaging system (110) with a set of resonating volumes (206) positioned in a base body (202), whereby the base body (202) has a spherical or ellipsoid shape in accordance with a volume of interest (203) of the MR imaging system (110), and the resonating volumes (206) are located at a circumference of the base body (202).

Abstract: The invention provides for a medical instrument (100, 500) comprising a magnetic resonance imaging system (102) for acquiring magnetic resonance data (142) from a subject (118) within an imaging zone (108). The magnetic resonance imaging system comprises: a main magnet (104) for generating a B0 magnetic field within the imaging zone; a memory (134, 136) containing machine executable instructions (160, 162, 164, 166) and pulse sequence commands (140); a processor (130) for controlling the medical instrument.

Abstract: In an MR imaging method and apparatus, a portion of a body placed in an examination volume of an MR device is subjected to an imaging sequence of RF pulses and switched magnetic field gradients. The imaging sequence is a stimulated echo sequence including i) two preparation RF pulses (?) radiated toward the portion of the body during a preparation period (21), and ii) reading RF pulses (?) radiated toward the portion of the body during an acquisition period (22) temporally subsequent to the preparation period (21). FID signals (I1) and stimulated echo signals (I2) are acquired during the acquisition period (22) with equal T2*-weighting. A B1 map indicating a spatial distribution of the RF field of the preparation RF pulses within the portion of the body is derived from the acquired FID (I1) and stimulated echo (I2) signals.