Patent classifications
G01R33/5607
MEASUREMENT OF BLOOD VOLUME USING VELOCITY-SELECTIVE PULSE TRAINS ON MRI
The present invention is directed to a system and method for measuring blood volume using non-contrast-enhanced magnetic resonance imaging. The method of the present invention includes a subtraction-based method using a pair of acquisitions immediately following velocity-sensitized pulse trains for the label module and its corresponding control module, respectively. The signal of static tissue is canceled out and the difference signal comes from the flowing blood compartment above a cutoff velocity. After normalizing to a proton density-weighted image acquired separately and scaled with the blood T1 and T2 relaxation factors, quantitative measurement of blood volume is then obtained.
Quantifying breast tissue changes with spectrally selective MRI and MRS
Systems and methods for magnetic resonance analysis and imaging are provided. IN particular, pulse sequences for DWI, APT, and MRS analysis and imaging are provided which rely on an RF excitation pulse for the signal of interest, followed by one or more refocusing pulses and acquisition steps, based on the type of imaging.
Interleaved black and bright blood imaging for interleaved dynamic contrast enhanced magnetic resonance imaging
A magnetic resonance system (10), and corresponding method, image a subject using a conversion-free interleaved black and bright blood imaging (cfIBBI) sequence. A MR scanner (12) is controlled to perform a plurality of repetitions of a black blood imaging sequence (52). The black blood imaging sequence (52) includes a tissue nulling sub-sequence followed by a black blood acquisition sub-sequence (56) performed a time interval (TI) after the tissue nulling sub-sequence. The MR scanner (12) is further controlled to, between successive repetitions of the black blood imaging sequence (52), perform a bright blood imaging sequence (54) including the tissue nulling sub-sequence followed by a bright blood acquisition sub-sequence (58) performed the time interval (TI) after the tissue nulling sub-sequence. The time intervals (TI) of the black blood imaging sequence (52) and the bright blood imaging sequence (54) are of the same duration.
Magnetic resonance imaging apparatus with segmented data acquisition
To provide an imaging technique suitable for acquiring an image with reduced artifacts due to differences in signal intensity. An MR apparatus 100 acquires, in data acquisition periods A1, A2, and A3, data at part of grid points lying closer to a high-frequency region RH within a low-frequency region RL, and data at part of grid points lying closer to the low-frequency region RL within the high-frequency region RH. On the other hand, in a data acquisition period B, it acquires data at another part of grid points lying closer to the high-frequency region RH within the low-frequency region RL, and data at another part of grid points lying closer to the low-frequency region RL within the high-frequency region RH.
Method for non-contrast enhanced magnetic resonance angiography
A method for performing a non-contrast-enhanced magnetic resonance angiography (“MRA”) for a subject is provided. The method includes directing a magnetic resonance imaging (“MRI”) system to perform a pulse sequence to acquire k-space data from imaging slices that are oriented away from an axial direction of the subject. The method includes repeating the pulse sequence for a plurality of imaging slices, wherein a field-of-view (“FOV”) of at least one of the plurality of imaging slices is shifted by a predetermined value. The method also includes reconstructing, using the acquired k-space data, one or more angiographic images indicative of the subject's vasculature.
MR ELECTRIC PROPERTIES TOMOGRAPHY WITHOUT CONTRAST AGENT
The invention relates to a method of MR imaging of an object (10) placed in an examination volume of a MR device (1). It is an object of the invention to enable MR signal acquisition in a single scan providing the necessary information for electric properties imaging (EPT), namely a phase map as well as tissue boundaries. The method of the invention comprises the following steps: —subjecting the object (10) to a multi echo steady state imaging sequence or a fast spectroscopic imaging sequence comprising RF pulses and switched magnetic field gradients, wherein two or more echo signals are generated after each RF excitation; —acquiring the echo signals; —deriving a magnitude image and a phase map from the acquired echo signals, which phase map represents the spatial RF field distribution induced by the RF pulses in the object (10); and —reconstructing an electric conductivity map from the magnitude image and from the phase map, wherein tissue boundaries are derived from at least the magnitude image. Moreover, the invention relates to a MR device for carrying out this method as well as to a computer program to be run on a MR device.
MAGNETIC RESONANCE TOMOGRAPHY APPARATUS AND METHOD FOR THE OPERATION THEREOF
In a magnetic resonance tomography scanner and an operating method therefor, a scanning volume is subdivided in a slice direction into multiple scanning slices, and the scan data of each of the scanning slices are acquired by a scan sequence allocated to the respective scanning slice. Each scan sequence has at least one preparation pulse allocated to the scanning slice, which causes nuclear spin excitation throughout the whole scanning volume. At least two scan sequences are implemented that differ with regard to a coil current fed during the preparation pulse to a field correction coil of the scanner for reducing a local inhomogeneity of a basic magnetic field, or that differ with regard to at least one pulse parameter of the preparation pulse. The respective coil current and/or pulse parameter is determined depending on the position of the scanning slice allocated to the respective scan sequence in the scanning volume.
Magnetic Resonance Method And Apparatus For Quantitative Time-Resolved Assessment Of Tissue Displacement And Related Biomarker Parameters With Blood Suppression In The Whole Cardiac Cycle
Embodiments relate to acquiring magnetic resonance (MR) images with suppressed residual blood signal in the early cardiac phases, leading to images with a preferred dark-blood appearance throughout the entire cardiac cycle, which improves accuracy of subsequent post-processing algorithms. The acquisition of the desired blood suppressed tissue images is achieved through a double inversion recovery pulse in DENSE sequences. The double inversion recovery pulse is applied after an electrocardiogram (ECG) trigger at a beginning point of a repetition time period, followed by a displacement encoding module at an inversion time during the repetition time period and a readout module comprised of a plurality of frames during a remainder of the repetition time period. The displacement encoding module applies a labelling process on the tissue, while the readout module applies an un-labelling process. The readout module comprises an imaging sequence adapted to acquire DENSE images.
MAGNETIC RESONANCE IMAGING APPARATUS AND METHOD OF SCANNING MAGNETIC RESONANCE IMAGE USING THE SAME
A magnetic resonance imaging (MRI) apparatus includes a radio frequency (RF) controller configured to, for a repetition time period, control the MRI apparatus to apply, to an object, an RF preparation pulse having a coverage area covering two or more slices among a plurality of slices of the object, control the MRI apparatus to apply, to the object, RF pulses respectively corresponding to the plurality of slices, and move the coverage area. The MRI apparatus further includes a data acquirer configured to acquire magnetic resonance signals from the plurality of slices during the repetition time period.
Medical image diagnosis support device and magnetic resonance imaging apparatus
Two or more learning images generated for a first subject or a second subject and one or more correct answer images generated for the second subject or a third subject are received. In a case where pixel values of corresponding pixels of the two or more learning images are synthesized by using a synthesis parameter value, the parameter value at which the synthesized pixel values are close to a pixel value of a corresponding pixel of the correct answer image is obtained. An image generated for the first subject and having the same type as the two or more learning images is received as an examination target image. A synthesized image desired by a user is generated by synthesizing pixel values of corresponding pixels of the two or more examination target images by using the synthesis parameter value.