Patent classifications
G01R33/5608
SYSTEMS AND METHODS FOR LOW FIELD MR/PET IMAGING
Systems and methods of PET attenuation correction using low-field MR image data includes receiving a first set of image data and a set of low-field magnetic resonance (MR) image data. An attenuation correction map is generated from the low-field MR image data using a first trained neural network. At least one attenuation correction process is applied to the first set of image data based on the attenuation correction map to generate at least one clinical attenuation-corrected image.
QUANTITATIVE DYNAMIC MRI (QDMRI) ANALYSIS AND VIRTUAL GROWING CHILD (VGC) SYSTEMS AND METHODS FOR TREATING RESPIRATORY ANOMALIES
A method of analyzing thoracic insufficiency syndrome (TIS) in a subject by performing quantitative dynamic magnetic resonance imaging (QdMRI) analysis. The QdMRI analysis includes performing four-dimensional (4D) image construction of a TIS subject's thoracic cavity. The 4D image includes a sequence of two dimensional (2D) images of the TIS subject's thoracic cavity over a respiratory cycle of the TIS subject. The QdMRI analysis also includes segmenting a region of interest (ROI) within the 4D image, determining TIS measurements within the ROI, comparing the TIS measurements to normal measurements determined from ROIs in 4D images of the thoracic cavities of normal subjects that are not afflicted by TIS, and outputting quantitative markers indicating deviation of the thoracic cavity of the TIS subject relative to the thoracic cavities of the normal subjects.
Magnetic resonance imaging apparatus, image processing apparatus, and phase correcting method
To provide a technique in which, in imaging using an EPI method, an occurrence of an artifact when phase correction is performed for each channel is avoided and the phase correction is accurately performed. A common phase correction value to be applied to data of all channels is calculated using pre-scan data of each channel. The common phase correction value is obtained by combining a difference phase obtained for each of the channels. The difference phase is obtained by complex integration, while an absolute value of each channel is maintained as it is. The combination is performed by complex average, and averaging processing according to a weight of the absolute value is performed. The occurrence of an artifact can be prevented by using the common phase correction value, and robust phase correction can be performed by including the weight of the absolute value.
Imaging method and device for nonlinear parallel magnetic resonance image reconstruction, and medium
There are provided a parallel rapid imaging method and device based on a complex number conjugate symmetry of multi-channel coil data and nonlinear GRAPPA image reconstruction, and a medium. The imaging method includes: obtaining virtual conjugate coil data by expanding the actual multi-channel coil data; combining actual multi-channel coil data and virtual multi-channel coil data to obtain a linear data term and a nonlinear data term; calibrating weighting factors of the linear data term and the nonlinear data term by using combined low-frequency full-sampling data (margins of the low-frequency full-sampling data includes parts of high-frequency data); reconstructing data which is under-sampled in a high-frequency region according to the calibrated weighting factors; fusing the low-frequency full-sampling data and the reconstructed data for the high-frequency region.
Method for providing a proposal for setting scan parameters and a computing unit for providing a setting aid
A proposal is provided for setting scan parameters comprising at least one value range scan parameter and at least two state scan parameters of a scan sequence of a magnetic resonance protocol for a magnetic resonance examination. A user is supported in the selection of the state scan parameters to be set by a computing unit that checks whether the selection of state scan parameters to be set made by the user comprises a permissible combination of settings and/or states. If an impermissible combination of settings and/or states is present, the computing unit ascertains at least one proposal with a permissible combination of settings and/or states for the state scan parameters to be set.
MR IMAGING USING DIXON-TYPE WATER/FAT SEPARATION WITH SUPPRESSION OF FLOW-INDUCED LEAKAGE AND/OR SWAPPING ARTIFACTS
The invention relates to a method of Dixon-type MR imaging. It is an object of the invention to provide a method that enables efficient and reliable Dixon water/fat separation, in particular using a bipolar acquisition strategy, while avoiding flow-induced leakage and swapping artifacts. According to the invention, an imaging sequence is executed which comprises at least one excitation RF pulse and switched magnetic field gradients, wherein pairs of echo signals are generated at two different echo times (TE1, TE2) and during two or more different cardiac phases (AW1, AW2). The echo signals are acquired and phase images are reconstructed therefrom. A final diagnostic image is reconstructed from the echo signal data using water/fat separation, wherein regions of flow and/or estimates of flow- induced phase errors are derived from the phase images to suppress or compensate for flow- induced leakage and/or swapping artifacts in the final diagnostic image. Therein, flow- induced phase offsets are determined by voxel-wise comparison of the phase images associated with the different cardiac phases. Moreover, the invention relates to a MR device (1) and to a computer program to be run on a MR device (1).
ACCELERATED TIME DOMAIN MAGNETIC RESONANCE SPIN TOMOGRAPHY
The present patent disclosure relates to a method and a device 700 for determining a spatial distribution of at least one tissue parameter within a sample on a time domain magnetic resonance, TDMR, signal emitted from the sample after excitation of the sample according to an applied pulse sequence, a method of obtaining at least one time dependent parameter relating to a magnetic resonance, MR, signal emitted from a sample after excitation of the sample according to an applied spin echo pulse sequence, and a computer program product for performing the methods. A TDMR signal model is used to approximate the emitted time domain magnetic resonance signal. The model is factorized into one or more first matrix operators that have a non-linear dependence on the at least one tissue parameter and a remainder of the TDMR signal model.
QUANTITATIVE MAPPING OF MRI RELAXATION PARAMETERS
Magnetic resonance imaging according to the present invention includes T1, T2, or diffusion mapping with improved image resolution. The improved image resolution is achieved by leveraging the delay in the image acquisition to remove the partial volume effect of fluid in and around the tissue being imaged.
MAGNETIC RESONANCE IMAGING APPARATUS AND IMAGING-TIME SHORTENING METHOD
A magnetic resonance imaging apparatus includes sequence control circuitry and processing circuitry. In CEST imaging the sequence control circuitry performs a first sequence and a second sequence under different saturation pulse conditions. The first sequence is for acquiring first magnetic resonance signals corresponding to a first frequency region of a k-space and second magnetic resonance signals corresponding to a second frequency region of the k-space. The second sequence is for acquiring third magnetic resonance signals corresponding to at least the first frequency region. The processing circuitry assigns the third magnetic resonance signals and the second magnetic resonance signals to a single k-space generated for the second sequence. Frequency including the first frequency region is lower than frequency including the second frequency region.
FAT SUPPRESSION USING NEURAL NETWORKS
In a method for determining a fat-reduced MR image, a first MR image is provided having, apart from the other tissue constituents, MR signals from only one of the two fat constituents, the first MR image is applied to a trained ANN, which was trained by first MR training data as the input data, the training data including, apart from the other tissue constituents, MR signals from only the one of the two fat constituents, and using second MR training data as a base knowledge, the second MR training data including, apart from the other tissue constituents, no MR signals from the two fat constituents; and an MR output image is determined from the trained ANN, to which the first MR image was applied, as a fat-reduced MR image, wherein the fat-reduced MR image includes, apart from the other tissue constituents, no MR signals from the two fat constituents.