Patent classifications
G01R33/3806
MEASUREMENT APPARATUS, DETECTION APPARATUS, AND MEASUREMENT METHOD
A measurement apparatus that includes a static magnetic field application part that applies a static magnetic field in a first direction to a measurement subject, a deflection magnetic field application part that applies a deflection magnetic field in a second direction different, to a portion of the measurement subject via a coil, a plurality of magnetic field detection elements respectively detect a magnitude of a magnetic field on the basis of an electromagnetic wave generated and propagated in a portion of the measurement subject due to an application of the deflection magnetic field, a calculation part that calculates an impedance distribution of at least a portion of a region where the electromagnetic wave is propagated inside the measurement subject, and an image information output part that generates and outputs an image showing information about inside the measurement subject.
Methods and apparatus for patient positioning in magnetic resonance imaging
According to some aspects, a magnetic resonance imaging system capable of imaging a patient is provided. The magnetic resonance imaging system comprising at least one BO magnet to produce a magnetic field to contribute to a BO magnetic field for the magnetic resonance imaging system and a member configured to engage with a releasable securing mechanism of a radio frequency coil apparatus, the member attached to the magnetic resonance imaging system at a location so that, when the member is engaged with the releasable securing mechanism of the radio frequency coil apparatus, the radio frequency coil apparatus is secured to the magnetic resonance imaging system substantially within an imaging region of the magnetic resonance imaging system.
Method for correcting inhomogeneity of the static magnetic field particularly of the static magnetic field generated by the magnetic structure of a machine for acquiring nuclear magnetic resonance images and MRI system for carrying out such method
Method for shimming a magnetic field which is generated by a magnetic structure, and which permeates a volume of space uses the following steps: measuring the magnetic field in a region of a volume of space permeated by the said magnetic field; determining a parameter which is a measure of the homogeneity of the magnetic field; defining a distribution of correction elements including a predetermined number of magnetic dipoles each having a predetermined magnetic charge and a predetermined position relatively to the magnetic structure generating the magnetic field; calculating the charges of each of the dipoles and the position of each of the dipoles of a distribution which minimizes the parameter being a measure of the homogeneity of the magnetic field; using the distribution of dipoles as the shimming distribution of dipoles to be positioned on the magnetic structure.
Radiation therapy system and method
The present disclosure relates to a therapeutic apparatus including an MRI apparatus configured to acquire MRI data with respect to a region of interest. The MRI apparatus may include a plurality of main magnetic field coils coaxially arranged along an axis. The MRI apparatus may also include a plurality of shielding coils arranged coaxially along the axis. A current within at least one of the shielding coils may be in the same direction with a current within the main magnetic field coils.
Noise suppression methods and apparatus
According to some aspects, a method of suppressing noise in an environment of a magnetic resonance imaging system is provided. The method comprising estimating a transfer function based on multiple calibration measurements obtained from the environment by at least one primary coil and at least one auxiliary sensor, respectively, estimating noise present in a magnetic resonance signal received by the at least one primary coil based at least in part on the transfer function, and suppressing noise in the magnetic resonance signal using the noise estimate.
Adaptive shim coils for MR imaging
Systems and methods involving: a housing having a bore in which a subject to be imaged is placed; a main magnet configured to generate a volume of magnetic field within the bore, the volume of magnetic field having inhomogeneity below a defined threshold; gradient coils configured to linearly vary the volume of magnetic field as a function of spatial location; pulse-generating coils configured to generate and apply radio frequency (RF) pulses to the volume of magnetic field in sequence to scan the portion of the subject; shim gradient coils configured to perturb a spatial distribution of the linearly varying volume of magnetic field; and a control unit configured to operate the gradient coils, pulse-generating coils, and shim gradient coils such that only the user-defined region within the volume of magnetic field is imaged.
MAGNETIC RESONANCE IMAGING
Improved magnetic resonance imaging systems, methods and software are described including a low field strength main magnet, a gradient coil assembly, an RF coil system, and a control system configured for the acquisition and processing of magnetic resonance imaging data from a patient while utilizing a sparse sampling imaging technique.
APPARATUS AND METHOD FOR C-ARM MRI WITH ELECTROPERMANENT MAGNETS
A method and apparatus for accessing and imaging at least one body part of interest may position a subject in an imaging system to partially encloses the subject and partially expose the subject, and access at least one body part of the subject that is exposed outside the imaging system for a procedure. The at least one exposed body part is positioned to be imaged by the imaging system.
Flowmeter
Flow measurement of hydrogen density, volumetric concentrations, and longitudinal relaxation times and transverse relaxation times have all n components in pairs different to each other. The method has the steps of: enclosing a mixture inside a probe volume and polarizing the mixture with a magnetic field; measuring the mixture enclosed inside the probe volume in terms of its longitudinal or transverse relaxation behaviour by means of pulsed electromagnetic waves at least n times with a different volumetric share of its components to measure at least n different relaxation curves; obtaining the relaxation times from the relaxation curves; obtaining the thermal equilibrium magnetizations M.sub.0 of the individual components from the relaxation curves; and correlating yielded thermal equilibrium magnetizations M.sub.0 of the individual components to calculate the hydrogen densities and the volumetric share of the components for each relaxation curve.
Magnetic resonance scanner and magnetic resonance imaging system
A magnetic resonance imaging system comprises a field generation unit and a supporting structure for providing structural support for the field generation unit, wherein the field generation unit comprises at least one magnet for generating a B0 magnetic field and an opening configured to provide access to an imaging volume positioned in the B0 magnetic field along at least one direction and wherein the at least one direction is angled with respect to a main direction of magnetic field lines of the B0 magnetic field in the imaging volume.