G01R33/3852

MULTI-PURPOSE GRADIENT ARRAY FOR MAGNETIC RESONANCE IMAGING
20180011156 · 2018-01-11 ·

A system for multi-slice magnetic resonance imaging (MM) comprises a gradient coil array comprising a plurality of independent coils distributed about an enclosure; and a controller configured to concurrently actuate said plurality of coils so as to generate a spatially-varying magnetic field within said enclosure such that for at least first and second volumetric slices, a magnetic field magnitude associated with at least one location in the first volumetric slice is substantially equal to a magnetic field magnitude associated with a respective location in the second volumetric slice.

Systems and methods for actual gradient waveform estimation

The present disclosure provides a system for MRI. The system may obtain MRI scan data of a subject by directing an MRI scanner to perform an MRI scan on the subject according to a first gradient waveform. The system may also determine a second gradient waveform based on the first gradient waveform and a gradient waveform determination model. The gradient waveform determination model may have been trained according to a machine learning algorithm. The system may further generate a target reconstruction image of the subject based on the second gradient waveform and the MRI scan data.

Avoidance of Artifacts in Measurement Data Captured Using a Magnetic Resonance System

A method for avoiding artifacts in measurement data captured using a magnetic resonance system which has a gradient unit. The method includes loading data which characterizes the gradient unit of the magnetic resonance system; loading a measurement protocol to be used for capturing the measurement data, wherein the measurement protocol includes gradients to be switched and RF excitation pulses and RF refocusing pulses to be irradiated, wherein, after irradiation of an RF excitation pulse, a train of at least two RF refocusing pulses is irradiated and measurement data is captured after each RF refocusing pulse; determining compensation gradients which, after the capture of the measurement data, are to be switched after a final RF refocusing pulse of the train of RF refocusing pulses associated with the RF excitation pulse and before a following RF excitation pulse as a function of the loaded measurement protocol and of the data which characterizes the gradient unit; and carrying out the measurement protocol using the determined compensation gradients.

MAGNETIC RESONANCE IMAGING SYSTEM WITH INTENTIONAL GRADIENT NOISE

The present invention relates to a magnetic resonance imaging system (10), comprising at least one gradient coil (20), and a processing unit (30). The processing unit is configured to control a gradient coil to produce intentional noise for sedation monitoring of a patient.

Method of reducing spatial extent of gradient coil current feeding connectors

Magnetic resonance imaging (MRI) systems and methods, involving: a main magnet configured to generate a magnet field for MRI; a transmit radio frequency (RF) coil assembly configured to transmit an RF pulse into a portion of a subject; an RF coil assembly configured to, in response to the an RF pulse, receive MR signals emitted from the portion of the subject; and a gradient coil assembly having coil windings arranged in a radial layer and a first set of electrical connectors embedded in the radial layer to reduce a radial extent occupied by the gradient coil assembly, an electrical connector in the first set of electrical connectors configured to cross over a portion of the coil windings in the radial layer, the first set of electrical connectors configured to drive the coil windings with a current sufficient to generate a perturbation in the magnet field such that the MR signals encode an MR image based on the perturbation, and the radial layer having a depressed area configured to radially constrain the electrical connector.

Energizing and discharging a superconducting magnet of an MRI system

A magnetic resonance imaging (MRI) system includes a superconducting magnet assembly with a superconducting field coil for generating a stationary uniform main magnetic field. A gradient system includes a gradient coil for generating gradient magnetic fields and a gradient amplifier which is connectable to the gradient coil for driving the gradient coil. A switch assembly is adapted for galvanically coupling the superconducting field coil to the gradient amplifier. In this way, it is possible for energizing and discharging a superconducting magnet of an MRI system in an easy and cost-efficient way.

MR system with improved protection against cardiostimulation

A method for operating an MR system with a gradient pulse amplifier unit that has an end stage connected to a gradient coil with switching elements is provided. The gradient pulse amplifier unit includes a modulator for actuating the switching elements, and lockout switches interconnected in signal paths from the modulator to the switching elements. The gradient pulse amplifier unit includes feeder circuit breakers interconnected in at least some signal paths from the modulator to the switching elements. The circuit breakers are connected in the associated signal paths downstream of the lockout switches. A gradstop unit configured to receive at least one shut-off signal and actuate the lockout switches and the feeder circuit breakers. When the gradstop unit receives a shut-off signal, the gradstop unit actuates the lockout switches to lock out and the feeder circuit breakers to output an actuation signal to the switching elements.

Method, Apparatuses and System for Correcting an Influence of an Interference Effect on a Gradient System

In a method for correcting an influence of an interference effect on a gradient system of a MR apparatus during a MR scan, a gradient pulse is emitted by an amplifier of the gradient system, a gradient sequence is established, an output signal of the amplifier is captured for the gradient pulse, a transfer function is established, and an output signal of the amplifier is established such that the gradient system provides an expected gradient sequence.

Method for providing setting parameter sets for a magnetic resonance facility, method for operating a magnetic resonance facility, provision facility, magnetic resonance facility and computer program

In a method for providing setting parameter sets for at least one measuring protocol described by protocol parameters for acquiring magnetic resonance data with a magnetic resonance facility, setting parameter set is determined for each of at least two temperature status categories of the magnetic resonance facility using a temperature model describing a development of a temperature status of at least one component of the magnetic resonance facility. The method also includes preventing overheating of the at least one component due to the measurement with the measuring protocol being repeated a maximum number of times for a specified number of repetitions.

Safety structure of a magnetic resonance apparatus

A magnetic resonance apparatus with a safety structure for monitoring a safety-related function is provided. The safety structure includes a control path that is configured to control the safety-related function, and a first protect path and a second protect path. The first protect path and the second protect path are configured to acquire a safety-related parameter of the safety-related function. The first protect path is configured to identify a hazardous situation, independently of the control path and the second protect path, based on the safety-related parameter that the first protect path acquires. The second protect path is configured to identify a hazardous situation, independently of the control path and the first protect path, based on the safety-related parameter that the second protect path acquires. The first protect path and the second protect path are each configured to transfer the magnetic resonance apparatus into a safe state in a hazardous situation.