Siemens Healthcare Gmbh

Siemens Aktiengesellschaft

Case Western Reserve University

Siemens Healthineers Ag

Johns Hopkins University

New York University

Mathias Nittka

Gregor Koerzdoerfer

Peter Speier

David Grodzki

Theresa Bachschmidt

Thorsten Feiweier

Mark A Griswold

Mariappan S Nadar

Boris Mailhe

Andreas Greiser

Thorsten Speckner

Sultan Haider

Josef Pfeuffer

Xiao Chen

Simon Arberet

Heiko Meyer

Yun Jiang

Thomas Kluge

Stefan Huwer

Jianing Pang

Gregor Körzdörfer

Gregor Korzdorfer

Guillaume Daval Frerot

Mario Zeller

Dominik Paul

Berthold Kiefer

Jianmin Wang

Stephan Kannengiesser

Matthias Fenchel

Björn Heismann

Daniel Nico Splitthoff

Vladimir Jellus

Esther Raithel

Uvo Hölscher

Jan Fritz

Stephan Kannengieβer

Zhigen Zhao

Bjoern Jakoby

Aurélien Stalder

Beatriz Fusaro Guimaraes

Joshua Shiloh Alden

Bernd Kühn

Torsten Ehlers

Techniques are disclosed for acquiring data of an examination object in at least two slices by means of a pulse sequence. Time intervals between excitations of neighboring slices and associated minimum intervals are determined. From these, time intervals to be adapted between excitations of neighboring slices are determined and adapted before a measurement protocol is executed, with the adapted time intervals. Through the determination of a minimum time interval between excitations of neighboring slices and the adaptation of the time intervals between excitations of neighboring slices, a falsification of measurement results can be avoided, measurement time of the chosen measurement protocol is not increased, and the user is not restricted in their choice of the slices to be excited.

Acquisition of data of an examination object by means of magnetic resonance with improved time management

A method for operating a magnetic resonance device is provided. The magnetic resonance device includes a component that has an operating limit in relation to a state parameter. The component uses a protocol to record magnetic resonance data. The protocol includes a magnetic resonance sequence and is described by protocol parameters. A protocol parameter set that, in relation to a protocol section, allows the protocol section to be repeated as often as desired without exceeding the operating limit is provided or determined. The method includes receiving a boost parameter from a user interface. At least for the protocol section, adaptation parameters are determined at least partially automatically based on the boost parameter, such that the desired number of repetitions described by the boost parameter is established while complying with the operating limit. Magnetic resonance data is recorded with the protocol using the determined adaptation parameters.

Operating a magnetic resonance device

Determining parameter values in image points of an examination object in an MR system by an MRF technique. Comparison signal waveforms, established using predetermined recording parameters, and each assigned to predetermined values of the parameters to be determined, are loaded. An image point time series of the examination object is acquired with an MRF recording method such that the acquired image point time series are comparable with the loaded comparison signal waveforms. A signal comparison of a section of the respective signal waveform of the acquired one image point time series is carried out with a corresponding section of loaded comparison signal waveforms to establish similarity values. The values of the parameters to be determined on the basis of the most similar comparison signal waveforms determined are determined, and then stored or output.

Magnetic resonance fingerprinting method

In a method for generating an image data set and a reference image data set: a first raw data set is provided that is acquired with a MR system and that includes measurement signals at read-out points in k-space that lie on a first k-space trajectory; a second raw data set is provided that is acquired with the same MR system and at the same examination object at read-out points that lie on a second, different k-space trajectory that is different from the first k-space trajectory; image data sets are reconstructed from the first raw data set; a reference image data set is reconstructed from the second raw data set; the reference image data set is compared with each image dataset to generate respective similarity values; and an image data set is selected having a greatest similarity value.

Method for generating at least one image data set and one reference image data set, data carrier, computer program product and magnetic resonance system

In a method for generating an image dataset and one reference image dataset: a first raw dataset is provided that is recorded using a MR system, the first raw dataset including measurement signals at readout points in k-space that lie on a first k-space trajectory; a second raw dataset is provided that is recorded using the same MR system and on the same examination object, the second raw dataset including measurement signals at readout points in k-space that lie on a second, different k-space trajectory; image datasets are reconstructed from the first raw dataset, where a separate equalization coefficient set is used before the reconstruction of each image dataset; a reference image dataset is reconstructed from the second raw dataset; the reference image data set is compared with each image dataset to generate respective similarity values; and the image dataset is selected with a greatest similarity value.

Method for generating at least one image dataset and one reference image dataset, data carrier, computer program product, and magnetic resonance system

MR fingerprinting method in which an MR pulse sequence succession is output multiple times. The MR pulse sequence succession has MR pulse sequences of a same type output successively in time and differing in terms of a pulse sequence parameter that is varied according to a predefined scheme. During the first output, raw data from a region of interest (ROI) of an object is acquired in a short time interval by the raw data being acquired at a low information density. The total information density of the acquisition is increased with each repetition of the output. After the acquisition, image data from the ROI is reconstructed based on the acquired raw data. MR-parameter value datasets associated with reference image data and having MR parameter values, are determined by comparing the reconstructed image data with the reference image data. MR parameter maps are determined based on the determined MR parameter values.

MR fingerprinting having adjustable measurement time

In a method and apparatus for determining parameter values in voxels of an examination object using magnetic resonance fingerprinting (MRF), a first signal comparison is made of signal characteristics of established voxel time series with first comparison signal characteristics. Further synthetic comparison signal characteristics are generated from the first comparison signal characteristics and values determined in the first signal comparison. The generated further comparison signal characteristics are used to perform a further signal comparison, with which values of at least a first and a second further parameter are determined. From the further comparison signal characteristics, a value of at least one further parameter is determined that could not necessarily already be determined in the first signal comparison.

Magnetic resonance fingerprinting method and apparatus

In a Method and a device for magnetic resonance imaging of a subject using a spoiled gradient echo sequence, a Bmagnetic field strength of at most 1.5 T is used during the sequence. As part of the sequence a slice select gradient acting as a spoil gradient is played out. Substantially simultaneously with the slice select gradient a predetermined RF pulse is played out in the sequence, wherein a time-bandwidth product of the RF pulse is set so that a majority of the energy of the RF pulse is transmitted in its central main lobe.

Method and device for magnetic resonance imaging, and corresponding computer program product

The disclosure facilitates determining patient motion during a magnetic resonance protocol. According to some examples, the patient motion may be corrected or compensated.

Magnetic resonance imaging and motion detection

For machine training and application of a trained complex-valued machine learning model, an activation function of the machine learning model, such as a neural network, includes a learnable parameter that is complex or defined in a complex domain with two dimensions, such as real and imaginary or magnitude and phase dimensions. The complex learnable parameter is trained for any of various applications, such as MR fingerprinting, other medical imaging, or non-medical uses.

Complex-valued neural network with learnable non-linearities in medical imaging

A method for performing magnetic resonance fingerprinting includes acquiring a plurality of MR image datasets using at least two pulse sequence types, the plurality of MR image datasets representing signal evolutions for image elements in a region of interest, comparing the plurality of MR image datasets to a dictionary of signal evolutions to identify at least one parameter of the MR image datasets and generating a report indicating the at least one parameter of the MR image datasets.

System and method for magnetic resonance fingerprinting using a plurality of pulse sequence types

Machine training a network for and use of the machine-trained network are provided for tissue parameter estimation for a magnetic scanner using magnetic resonance fingerprinting. The machine-trained network is trained to both reconstruct a fingerprint image or fingerprint and to estimate values for multiple tissue parameters in magnetic resonance fingerprinting. The reconstruction of the fingerprint image or fingerprint may reduce noise, such as aliasing, allowing for more accurate estimation of the values of the multiple tissue parameters from the under sampled magnetic resonance fingerprinting information.

Magnetic resonance fingerprinting image reconstruction and tissue parameter estimation

Techniques are disclosed for providing a first magnetic resonance fingerprinting dictionary using fingerprints having a first length. A transformation matrix is also utilized that is configured to shorten the fingerprints to a second length that is shorter than the first length. A second magnetic resonance fingerprinting dictionary may then be obtained by multiplying the first magnetic resonance fingerprinting dictionary with the transformation matrix, with the fingerprints of the magnetic resonance fingerprinting dictionary having the second length. This facilitates the storage of a MRF dictionary that takes up less storage space and decreases the time taken to perform scanning operations.

Magnetic resonance fingerprinting with dictionary recompression

A system and method is provided for acquisition of magnetic resonance fingerprinting ('MRF') data that includes determining a non-locally sequential sampling pattern for a Cartesian grid of k-space, performing a series of sequence blocks using acquisition parameters that vary between sequence blocks to acquire MRF data from a subject using the Cartesian grid of k-space and the determined non-locally sequential sampling pattern, assembling the MRF data into a series of signal evolutions, comparing the series of signal evolutions to a dictionary of known signal evolutions to determine tissue properties of the subject, and generating a report indicating the tissue properties of the subject.

System and method for magnetic resonance fingerprinting with non-locally sequential sampling of k-space

A magnetic resonance fingerprinting (MRF) method for determining parameter values in pixels of an examination object can use a magnetic resonance system with, for example, a constant magnetic field strength (e.g. of less than 1.5 tesla or a constant magnetic field strength of less than 0.5 tesla). The MRF method can be adapted for conditions that prevail with such low-field magnetic resonance systems, thus enabling the parameter values to be advantageously determined efficiently while simultaneously maintaining a high degree of quality.

Low-field magnetic resonance fingerprinting

Growing community of inventors

Baiersdorf, Germany

Mathias Nittka