G01R33/56536

Method and system for improved classification of constituent materials

An imaging system and method are disclosed. An MR image and measured B0 field map of a target volume in a subject are reconstructed, where the MR image includes one or more bright and/or dark regions. One or more distinctive constituent materials corresponding to the bright regions are identified. Each dark region is iteratively labeled as one or more ambiguous constituent materials. Susceptibility values corresponding to each distinctive and iteratively labeled ambiguous constituent material is assigned. A simulated B0 field map is iteratively generated based on the assigned susceptibility values. A similarity metric is determined between the measured and simulated B0 field maps. Constituent materials are identified in the dark regions based on the similarity metric to ascertain corresponding susceptibility values. The MRI data is corrected based on the assigned and ascertained susceptibility values. A diagnostic assessment of the target volume is determined based on the corrected MRI data.

MAGNETIC RESONANCE METHOD AND APPARATUS USING ATLAS-BASED MASKING FOR QUANTITATIVE SUSCEPTIBILITY MAPPING

In a magnetic resonance method and apparatus, deficiencies in conventional masking in quantitative susceptibility mapping (QSM) are addressed by the inclusion of an additional step in the conventional QSM post-processing pipeline. In this additional step, atlas-based segmentation techniques, which have been developed for morphological applications such as T1w MPRAGE are used in order to provide the mask. This mask is then fed to the remainder of the QSM post-processing pipeline.

MRI Rectal Tube
20190302203 · 2019-10-03 · ·

This is a unique medical device that will be used to optimize MRI imaging in the low pelvic region by displacing gas and fecal material from the rectum and sigmoid colon. The quality of MRI imaging depends very much on the homogeneity of the magnetic field within body tissues. Abrupt changes in tissue interface (air adjacent to solid tissue or fluid) creates field inhomogeneities that can adversely affect MRI quality.

This novel device is designed to minimize the inhomogeneities that are inherent in the pelvis during MRI examinations. This device is specifically designed to optimize the MR imaging environment in the low pelvic region. It is not a receiver coil or an immobilization device. This invention addresses the common problem of field inhomogeneity in MRI imaging due to rectal gas and fecal material.

Apparatuses and methods for cancellation of inhomogenous magnetic fields induced by non-biological materials within a patient's mouth during magnetic resonance imaging

This disclosure includes magnetic field correction devices and methods for using the same. In particular, some magnetic field corrections devices include an arch-shaped body configured to be worn outside of a user's mouth such that the arch-shaped body follows a contour of the user's face; and where the arch-shaped body comprises one or more sidewalls configured to be coupled to a plurality of members comprising magnetically permeable material. Other embodiments employ a forehead support, frame, and one or more straps coupled to an arch-shaped body. Other embodiments employ a hybrid of intraoral and external embodiments.

Deep Learning Method for Nonstationary Image Artifact Correction

A method for magnetic resonance imaging corrects non-stationary off-resonance image artifacts. A magnetic resonance imaging (MRI) apparatus performs an imaging acquisition using non-Cartesian trajectories and processes the imaging acquisitions to produce a final image. The processing includes reconstructing a complex-valued image and using a convolutional neural network (CNN) to correct for non-stationary off-resonance artifacts in the image. The CNN is preferably a residual network with multiple residual layers.

Medical apparatus
10408909 · 2019-09-10 · ·

The present invention relates to a medical apparatus which includes a motion mechanism which has at least one degree of freedom, an actuator configured to drive the motion mechanism and a control unit configured to control the actuator, and which operates in a magnetic field environment of an MRI, the medical apparatus including: a data storage unit in which data related to magnetic susceptibility of the actuator is stored; a calculating unit configured to calculate information related to an influence which the actuator exerts upon the magnetic field environment by calculation based on the magnetic susceptibility; and a communication unit configured to output the information to the MRI. An influence which an apparatus which operates in a strong magnetic field environment exerts upon an MR image can be reduced.

Method and magnetic resonance apparatus for acquiring magnetic resonance dataset with reduced susceptibility artifacts in the reconstruction image

In a method and apparatus for recording a magnetic resonance dataset of a volume of interest of an object, at least one gradient moment is calculated as a function of at least one jump in susceptibility that is present in the volume of interest, between two sections of the volume of interest. An excitation pulse is radiated and at least one compensation moment is activated in a part volume of the volume of interest, for the at least partial compensation of a gradient moment caused by the jump in susceptibility. The signal generated by the excitation pulse is read out.

Systems and methods for magnetic resonance imaging

A method for magnetic resonance imaging (MRI) may include obtaining a plurality of first magnetic resonance (MR) data sets related to a region of interest (ROI) of a subject. The plurality of first MR data sets may be collected based on two or more different values of a scan parameter. The method may also include determining a plurality of second MR data sets based on the plurality of first MR data sets. Each of the plurality of second MR data sets may correspond to at least two of the plurality of first MR data sets. The method may also include generate, based on the plurality of second MR data sets, a plurality of T1 weighted images of the ROI each of which corresponds to a target time point.

BO-CORRECTED SENSITIVITY ENCODING MAGNETIC RESONANCE IMAGING

The invention provides for a magnetic resonance imaging system (200, 300, 400) comprising a radio-frequency system (216, 214) comprising multiple coil elements (214) for acquiring magnetic resonance data (264). The magnetic resonance imaging system further comprises a memory (250) for storing machine executable instructions (260) and pulse sequence commands (262). The pulse sequence commands are configured for controlling the magnetic resonance imaging system to acquire the magnetic resonance data according to a SENSE imaging protocol. The magnetic resonance imaging system further comprises a processor (244) for controlling the magnetic resonance imaging system. Execution of the machine executable instructions causes the processor to: control (500) the magnetic resonance imaging system to acquire the magnetic resonance data using the pulse sequence commands; reconstruct (502) a set of folded magnetic resonance images (266) from the magnetic resonance data; calculate (504) a voxel deformation map (270) from a static magnetic field (B0) inhomogeneity map; calculate (506) a set of unfolding matrices (274) using a least partially a coil sensitivity matrix (272) for the multiple coil elements, wherein the set of unfolding matrices comprises at least one modified unfolding matrix, wherein the at least one modified unfolding matrix is calculated at least partially using the a coil sensitivity matrix and the voxel deformation map; and calculate (508) undistorted magnetic resonance image data (276) using the set of folded magnetic resonance images and the set of unfolding matrices.

SYSTEMS AND METHODS FOR IMAGE ARTIFACT REDUCTION IN SIMULTANEOUS MULTI-SLICE MAGNETIC RESONANCE IMAGING

A magnetic resonance imaging system includes an array radiofrequency coil and processing circuitry operatively linked to the array radiofrequency coil and configured to receive output signals from the array radiofrequency coil commensurate with a simultaneous multi-slice magnetic imaging characterized by simultaneous multi-slice parameters, estimate distorted regions of the image volume using either data obtained via a pre-scan or a pre-computed model, minimize overlap of the distorted regions with image voxels representing tissue to obtain optimized values of the simultaneous multi-slice parameters, configuring and executing the simultaneous multi-slice imaging sequence based on the optimized values of the simultaneous multi-slice parameters, and reconstruct simultaneous multi-slice images with minimized artifacts.