Patent classifications
G01R33/56358
Magnetic resonance examination system with a moveable patient carrier
In a magnetic resonance examination system, the patient carrier is mounted moveably in a direction transverse to the support surface and an RF antenna has a fixed geometrical relation to the support surface.
Systems and methods for generating an elastogram of brain tissue using mesoscopic wavelength ultrasound
Methods, systems, and devices for mechanically disturbing tissues of the central nervous system including a brain of a subject are provided. An elastogram of brain tissue may be generated using mesoscopic wavelength ultrasound composed of longitudinal waves in brain tissues to produce micromechanical disturbances of brain nuclei and circuits for characterization of their mechanical properties (e.g., stiffness, elasticity, rigidity, viscoelasticity). A magnetic resonance elastography (MRE) system includes an MRE engine in electronic communication with at least one transducer and with a magnetic resonance imaging (MRI) device. The MRE engine is configured to electronically control operation of the at least one transducer to emit ultrasound, to electronically receive, from the MRI device, at least one signal indicative of measurements of displacement of the brain tissue by the ultrasound, and to electronically generate an elastogram of the brain tissue based on the at least one signal.
ELASTOGRAPHY FOR LIGAMENT CHARACTERIZATION
Methods and system for characterizing ligament properties using elastography are disclosed. An ultrasound system capable of performing shear wave elasticity imaging and/or supersonic shear imaging may retrieve one or more images from a proposed surgical site. The one or more images may be provided to a surgical planning system that identifies one or more properties of ligaments proximate to the surgical site. Musculoskeletal simulations may be performed using the identified properties to preoperatively identify a surgical plan. Preoperative identification of a surgical plan may enable a surgeon to select from more fine-tuning options for a joint replacement than conventional systems.
TENSOR FIELD MAPPING
During operation, a system may apply an external magnetic field and an RF pulse sequence to a sample. Then, the system may measure at least a component of a magnetization associated with the sample, such as MR signals of one or more types of nuclei in the sample. Moreover, the system may calculate at least a predicted component of the magnetization for voxels associated with the sample based on the measured component of the magnetization, a forward model, the external magnetic field and the RF pulse sequence. Next, the system may solve an inverse problem by iteratively modifying the parameters associated with the voxels in the forward model until a difference between the predicted component of the magnetization and the measured component of the magnetization is less than a predefined value. Note that the calculations may be performed concurrently with the measurements and may not involve performing a Fourier transform.
TENSOR FIELD MAPPING
During operation, a system may apply an external magnetic field and an RF pulse sequence to a sample. Then, the system may measure at least a component of a magnetization associated with the sample, such as MR signals of one or more types of nuclei in the sample. Moreover, the system may calculate at least a predicted component of the magnetization for voxels associated with the sample based on the measured component of the magnetization, a forward model, the external magnetic field and the RF pulse sequence. Next, the system may solve an inverse problem by, iteratively modifying the parameters associated with the voxels in the forward model until a difference between the predicted component of the magnetization and the measured component of the magnetization is less than a predefined value. Note that the calculations may be performed concurrently with the measurements and may not involve performing a Fourier transform.
Systems and Methods for Magnetic Resonance Phantoms
Embodiments of the disclosure provide a magnetic resonance (MR) phantom including a housing, a base medium disposed within the housing, and one or more compartment extending through the base medium, the one or more compartment comprising a crosslinked acrylamide-based polymer. The MR phantoms may be used as calibration phantoms for magnetic resonance elastography sequences and diffusion weighted images.
Multiband, multishot magnetic resonance elastography
A method and system provides an acquisition scheme for generating magnetic resonance elastography displacement data with whole-sample coverage, high spatial resolution, and adequate SNR in a short scan time. The method and system can acquire in-plane and through-plane k-space shots over a volume of a sample divided into a plurality of slabs that each include a plurality of non-adjacent slices to obtain three dimensional multiband, multishot data, can apply multiband radio frequency refocusing pulses to the sample, can acquire navigators before readout, and can correct for non-linear motion errors.
Tensor field mapping
During operation, a system may apply an external magnetic field and an RF pulse sequence to a sample. Then, the system may measure at least a component of a magnetization associated with the sample, such as MR signals of one or more types of nuclei in the sample. Moreover, the system may calculate at least a predicted component of the magnetization for voxels associated with the sample based on the measured component of the magnetization, a forward model, the external magnetic field and the RF pulse sequence. Next, the system may solve an inverse problem by iteratively modifying the parameters associated with the voxels in the forward model until a difference between the predicted component of the magnetization and the measured component of the magnetization is less than a predefined value. Note that the calculations may be performed concurrently with the measurements and may not involve performing a Fourier transform.
METHODS, SYSTEMS, AND COMPUTER-READABLE MEDIA FOR NONDESTRUCTIVELY MEASURING PHYSICAL PROPERTIES OF A MATERIAL BY OBSERVING INDUCED DISPLACEMENTS USING DIFFERENT FOCAL CONFIGURATIONS
A method for quantitatively measuring a physical characteristic of a material includes performing one or more interrogations of a material sample, each interrogation using a push focal configuration. The method further includes taking measurements of displacement over time of a material sample caused by the one or more interrogations. Each measurement uses an interrogation focal configuration. The method further includes determining a physical characteristic of the material sample based on the measurements of displacement over time of the material sample. According to the method, at least one of the following is true: a tracking focal configuration used for one of the measurements is different from a tracking focal configuration used for another of the measurements; and a push focal configuration used for one of the interrogations is different from a push focal configuration used for another of the interrogations.
Echo-planar imaging magnetic resonance elastography pulse sequence
Magnetic resonance elastography (MRE) is an imaging technique for estimating the stiffness of tissues non-invasively. Shear waves are generated via external mechanical actuation and the tissue imaged with a specially designed MR pulse sequence. The resulting images are used to calculate the underlying properties. The application provides methods for acquiring MRE data using a single shot, echo planar imaging readout. The purpose of the developed sequence is to acquire MRE data using a single-shot, echo-planar imaging readout, avoiding to need for off-line image processing.