Patent classifications
G01R33/4833
METHOD AND APPARATUS FOR IMAGING A JAW REGION
The disclosure relates to a technique for providing an image of diagnostically relevant area of a jaw region of a patient by means of a magnetic resonance apparatus by capturing information about the jaw region of the patient, which comprises at least one reference to a position and/or an extent of the diagnostically relevant area of the jaw region. The technique also includes adjusting a parameter of a magnetic resonance measurement as a function of the captured information about the jaw region of the patient, carrying out the magnetic resonance measurement with the adjusted parameter, capturing image data of the jaw region of the patient, reconstructing an image of the diagnostically relevant area of the jaw region as a function of the captured image data, and providing the image of the diagnostically relevant area of the jaw region of the patient.
TERRITORY MAPPING IN PSEUDO-CONTINUOUS ARTERIAL SPIN LABELING
Systems and methods for localized pseudo-continuous ASL (pCASL) of arterial blood local multi-coil arrays in an MRI system allow a series of pulses to selectively label blood with an on-resonance magnetic field in one or more arteries in a labeling plane while masking blood in others with an off-resonance magnetic field. This allows perfusion imaging and is well suited for imaging of cerebral blood flow.
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 B0 magnet to produce a magnetic field to contribute to a B0 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.
MULTI-SHOT ECHO PLANAR IMAGING USING REORDERED SEGMENTS AND RF EXCITATION PULSE PHASE AND SLICE PROFILES MATCHED ACROSS INTERLEAVES
Described here are systems and methods for producing images with a magnetic resonance imaging (“MRI”) system using a high-resolution, motion-robust, artifact-free segmented echo planar imaging (“EPI”) technique. In particular, a fast low angle excitation echo planar imaging technique (“FLEET”) using variable flip angle (“VFA”) radio frequency (“RF”) excitation pulses that are specifically designed to have a flat magnitude and phase profile across a slice for a range of different flip angles.
Systems and methods for design of magnetic resonance imaging slice-select pulses
A system, non-transitory computer-readable medium, and method of designing quiet variable-rate MRI slice-select pulses includes creating discretized first slice-select constant-amplitude gradient and RF waveforms, associating discretized time points having a first constant time increment with the first waveforms, selecting a scaling function that smooths the gradient waveform when multiplied together, multiplying the gradient and RF waveforms by the corresponding value of the scaling function to create second gradient and RF waveforms, dividing the time increment between the discretized time points by the corresponding value of the scaling function to create a remapped time increment, cumulatively summing the remapped time increments to create a remapped time scale, interpolating the second gradient and RF waveforms along the remapped time scale to form final gradient and RF waveforms, and providing the final gradient and RF waveforms for incorporation into an MRI pulse sequence.
SELECTIVE SAMPLING FOR ASSESSING STRUCTURAL SPATIAL FREQUENCIES WITH SPECIFIC CONTRAST MECHANISMS
The disclosed embodiments provide a method for acquiring MR data at resolutions down to tens of microns for application in in vivo diagnosis and monitoring of pathology for which changes in fine tissue textures can be used as markers of disease onset and progression. Bone diseases, tumors, neurologic diseases, and diseases involving fibrotic growth and/or destruction are all target pathologies. Further the technique can be used in any biologic or physical system for which very high-resolution characterization of fine scale morphology is needed. The method provides rapid acquisition of signal at selected values in k-space, with multiple successive acquisitions at individual k-values taken on a time scale on the order of microseconds, within a defined tissue volume, and subsequent combination of the multiple measurements in such a way as to maximize SNR. The reduced acquisition volume, and acquisition of only signal values at select places in k-space, along selected directions, enables much higher in vivo resolution than is obtainable with current MRI techniques.
METHODS FOR PRODUCING A SLICE-SELECTIVE ADIABATIC T2 PREPARATION PULSE AND DEVICES THEREOF
A method, magnetic resonance imaging computing device, and a non-transitory computer readable medium for producing a slice-selective adiabatic magnetization T.sub.2 preparation pulse for magnetic resonance imaging. A pulse control signal including an adiabatic half passage pulse control signal, an adiabatic full passage pulse control signal, and a reverse adiabatic half passage pulse control signal is generated. A plurality of slice-selective linear phase subpulse control signals are generated. The pulse control signal is sampled using the plurality of slice-selective linear phase subpulse control signals to generate a slice-selective adiabatic magnetization T.sub.2 preparation control signal. The slice-selective adiabatic magnetization T.sub.2 preparation control signal is output to a waveform generator to produce the slice-selective adiabatic magnetization T.sub.2 preparation pulse.
MAGNETIC RESONANCE IMAGING APPARATUS AND METHOD OF GENERATING MAGNETIC RESONANCE IMAGE BY USING THE SAME
A magnetic resonance imaging apparatus includes a radio frequency (RF) controller configured to, during a repetition time (TR) period among TR periods, apply at least one RF pulse corresponding to a first slice to an object, and apply a navigator RF pulse corresponding to a second slice adjacent to the first slice to the object, a data obtainer configured to, during the TR period, obtain first k-space data corresponding to the applied at least one RF pulse, and obtain second k-space data corresponding to the applied navigator RF pulse, and an image processor configured to generate navigator images, based on pieces of second k-space data that are obtained during the TR periods, the pieces comprising the second k-space obtained during the TR period, correct the first k-space data, based on the navigator images, and generate a magnetic resonance image of the first slice, based on the corrected first k-space data.
Transmit coil frequency response correction for magnetic resonance imaging
Methods for correcting a non-uniform power response of a radiofrequency (“RF”) transmit coil used in magnetic resonance imaging (“MRI”) are described. Transmit power response data for an RF transmit coil are processed to compute RF amplitude scaling factors for the RF transmit coil as a function of transmit frequency offset. The RF amplitude scaling factors can be used to correct transmitted RF power, and thus flip angle, to be more uniform over a range of transmit frequency offsets, as may be encountered when imaging with lower field MRI systems or MRI systems with high strength or asymmetric gradients.
MRI scanner with active interference suppression and interference suppression method for an MRI scanner
An MRI scanner and a method for operation of the MRI scanner are provided. The MRI scanner has a first receiving antenna for receiving a magnetic resonance signal from a patient in a patient tunnel, a second receiving antenna for receiving a signal having the Larmor frequency of the magnetic resonance signal, and a receiver. The second receiving antenna is located outside of the patient tunnel or near an opening thereof. The receiver has a signal connection to the first receiving antenna and the second receiving antenna and is configured to suppress an interference signal by the second receiving antenna in the magnetic resonance signal received by the first receiving antenna.