Patent classifications
G01R33/5635
Magnetic resonance imaging apparatus
In one embodiment, a magnetic resonance imaging apparatus includes memory circuitry configured to store a predetermined program; and processing circuitry configured, by executing the predetermined program, to set an FSE type pulse sequence in which an excitation pulse is followed by a plurality of refocusing pulses, the plurality of the refocusing being divided into at least a first pulse group subsequent to the excitation pulse and a second pulse group subsequent to the first pulse group, the first pulse group including refocusing pulses having a predetermined high flip angle, and the second pulse group including refocusing pulses having flip angles decreased from the predetermined high flip angle toward a flip angle of zero, and generate an image of an object from respective MR signals corresponding to the plurality of refocusing pulses acquired by applying the fast spin echo type pulse sequence to the object.
4D Flow Measurements Of The Hepatic Vasculatures With Two-Dimensional Excitation
A computer-implemented method of visualizing blood flow through a patient using magnetic resonance imaging (MRI) includes receiving an image of the portal venous system of the patient's liver at a full field of view. A reduced field of view is defined which encompasses the portal venous system of the patient's liver and excludes extraneous anatomy in the full field of view. A navigator area is defined in the full field of view and outside of the reduced field of view. Transmit channels are used to selectively excite the reduced field of view and the navigator area throughout a cardiac cycle of the patient. Measurement data is acquired in response to the selective excitation. The acquired data is used to generate time-resolved 3D datasets. Additionally, a 3D visualization of blood flow though the portal venous system is generated based on the time-resolved 3D datasets.
Method and magnetic resonance apparatus for determination of magnetic resonance angiography images using time-of-flight angiography
In a method and apparatus, magnetic resonance angiography images of an examination volume of a patient are obtained using time-of-flight angiography in a magnetic resonance scanner. By continuous recording, a number of two-dimensional slice images covering the examination volume along an axial direction are acquired in a slice-by-slice layer-wise, such as with overlapping. The slice images are divided into groups of, in each case, a predetermined number of consecutive slice images in the axial direction. A maximum intensity projection image is determined for each group, and the angiography images are determined as the maximum intensity projection images and/or dependent on the maximum intensity projection images.
Magnetic resonance (MR) imaging generating perfusion images with arterial spin labeling (ASL) and 3D radial pulse sequences
Systems and methods for reducing acoustic noise in a Magnetic Resonance Imaging (MRI) are provided. One method includes applying a labeling phase of an arterial spin labeling (ASL) pulse sequence to a region of interest, applying a three-dimensional (3D) radial pulse sequence to the region of interest to generate a tag image, applying a control phase of the ASL pulse sequence to the region of interest, and applying the 3D radial pulse sequence to the region of interest to generate a control image.
CARDIAC PHASE-RESOLVED NON-BREATH-HOLD 3-DIMENSIONAL MAGNETIC RESONANCE ANGIOGRAPHY
3D cine MR angiography systems and methods are disclosed for use during the steady state intravascular distribution phase of ferumoxytol. The 3D cine MRA technique enables improved delineation of cardiac anatomy in pediatric patients undergoing cardiovascular MRI.
STIMULATED ECHO SEQUENCE SCANNING MAGNETIC RESONANCE METHOD AND APPARATUS FOR HEART DIFFUSION IMAGING
In a method and magnetic resonance (MR) apparatus for heart diffusion imaging, when an ECG trigger signal by a computer that operates an MR scanner, the MR scanner is operated to acquire a navigator echo before a stimulated echo sequence, in order to detect diaphragm position information. When the first diaphragm position information is not located in an acquisition window, the stimulated echo sequence is not executed, and the computer waits to receive the next ECG trigger signal. The detection time of the navigator echo after the stimulated echo sequence as well as the acquisition time of the stimulated echo sequence, are thus eliminated when the first diaphragm position information does not meet requirements, so can significantly reduce scanning time, and increase the image SNR.
System And Method For Accelerated Angiographic Magnetic Resonance Imaging
A magnetic resonance method and system are provided for projection MR imaging of vascular structures within a subject, with scan times that are shorter than those needed for conventional techniques. Image acquisition sequences are synchronized with heartbeat cycles of the subject, and are configured to generate image data having a reduced spatial resolution in the projection direction perpendicular to a preselected projection plane. A reduction factor F quantifies this reduced resolution, such that the number of data acquisition sequences provided within each heartbeat cycle is F times as many as a comparable imaging protocol that generates full-resolution data. The total scan time can be reduced by a factor of F with negligible degradation in the projection image quality.
Magnetic resonance imaging apparatus and a method for determining trigger timing of CE-MRA scan
The present invention discloses an apparatus and a method for determining a trigger timing of a CE-MRA scan. The apparatus comprises: a blood flow velocity acquisition unit configured to acquire a blood flow velocity of a target vessel; and a trigger timing determination unit configured to determine the trigger timing for performing the CE-MAR scan on a CE-MRA scan region according to the blood flow velocity and a predetermined image acquisition condition during a monitoring scan. The apparatus and method take the blood flow velocity into consideration, and can determine the trigger timing of the CE-MRA scan automatically and accurately.
Method for performing an angiographic measurement
A method is for performing an angiographic measurement of a main measurement region of a patient via a magnetic resonance system. An embodiment of the method includes performing at least one overview measurement to generate overview-measurement data; defining, using the overview-measurement data, the main measurement region and a first measurement region, the first measurement region differing from the main measurement region; performing a first time-resolved measurement in the first measurement region defined to generate first time-resolved measurement data; detecting an injected contrast agent bolus in the first measurement region using the first time-resolved measurement data; determining a flow rate of the injected contrast agent bolus detected; setting at least one measurement parameter of the angiographic measurement according to the flow rate determined; and performing the angiographic measurement of the main measurement region of the patient in the magnetic resonance system using the at least one measurement parameter set.
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.