Patent classifications
G01R33/5602
FREE BREATHING MOTION CORRECTED PIXEL-WISE MRI MYOCARDIAL T1 PARAMETER MAPPING
A method for performing free breathing pixel-wise myocardial T1 parameter mapping includes performing a free-breathing scan of a cardiac region at a plurality of varying saturation recovery times to acquire a k-space dataset; generating an image dataset based on the k-space dataset; and performing a respiratory motion correction process on the image dataset. The respiratory motion correction process comprises selecting a target image from the image dataset, co-registering each image in the image dataset to the target image to determine a spatial alignment measurement for each image, and identifying a subset of the image dataset comprising images with the spatial alignment measurement above a predetermined value. Following the respiratory motion correction process, a pixel-wise fitting is performed on the image dataset to estimate T1 relaxation time values for the cardiac region. Then, a pixel-map of the cardiac region is produced depicting the T1 relaxation time values.
Magnetic resonance imaging device and method for generating image using same
The magnetic resonance imaging device in accordance with the example embodiments, the magnetic resonance imaging device has an advantage that it is capable of generating an image quickly having a high resolution while minimizing generation of artifacts by comprising a data processing unit configured to relocate, in a K-space, gradient echo data acquired during inversion time by an inversion pulse and spin echo data acquired after the lapse of the inversion time; and an image generating unit configured to generate a final image from the spin echo data and the gradient echo data, in order to generate a magnetic resonance image quickly using long inversion time by the inversion pulse.
Magnetic resonance imaging (MRI) apparatus and method of processing MR image
A magnetic resonance imaging (MRI) apparatus and a method of processing an MR image are provided. The MRI apparatus includes a scanner configured to acquire a first image that is a T1-weighted image and a second image that is a fluid attenuated inversion recovery (FLAIR) image by performing an MRI scan on a brain. The MRI apparatus further includes an image processor configured to determine a white matter region in the second image based on the first image and the second image, and detect a white matter hyperintensity (WMH) region in the determined white matter region. The MRI apparatus further includes an output interface configured to display the detected WMH region and a change in the WMH region over time.
Systems and methods for enhancement of resolution for strategically acquired gradient echo (stage) imaging
Systems and methods for high-resolution STAGE imaging can include acquisition of relatively low-resolution k-space datasets with two separate multi-echo GRE sequences. The multi-echo GRE sequences can correspond to separate and distinct flip angles. Various techniques for combining the low-resolution k-space datasets to generate a relatively high-resolution k-space are described. These techniques can involve combining low-resolution k-space datasets associated with various echo types. The STAGE imaging approaches described herein allow for rapid imaging, enhanced image resolution with relatively small or no increase in MR data acquisition time.
METHOD AND APPARATUS FOR RECORDING MAGNETIC RESONANCE DATA
In a method and apparatus for recording magnetic resonance (MR) data of a target region of a subject, the recording process is divided into subsections each follow the other after a repetition time. Before each recording of MR data of a subsection with a measurement sequence, an adiabatic preparatory pulse is activated that inverts the longitudinal magnetization of a saturation molecule type, from which no MR data are to be recorded. An excitation pulse is emitted spaced by an inversion time from the preparatory pulse. Before the first preparatory pulse, at least one adiabatic preparation pulse is emitted that inverts the longitudinal magnetization with a timing such that the longitudinal magnetization of the saturation molecule type at the time of the first preparatory pulse at a steady state value, which occurs again before the repetition time after each preparatory pulse.
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.
Background-Suppressed, Reduced Field-Of-View Radial Magnetic Resonance Imaging
Embodiments relate to a method and system to improve fat suppression and reduce motion and off-resonance artifacts in magnetic resonance imaging (MRI) by using a background-suppressed, reduced field-of-view (FOV) radial imaging. The reduction of such artifacts provides improved diagnostic image quality, higher throughput of MRI scans for the imaging center, and increased patient comfort. By using a small FOV radial acquisition that only encompasses the structures of interest, structures that cause motion artifacts, such as the anterior abdominal wall, bowel loops, or blood vessels with pulsatile flow, are excluded from the image. According to an embodiment, combining a small FOV radial acquisition with one or more background-suppression techniques minimizes the impact of artifacts caused by anatomy outside of the FOV.
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.
System for reducing artifacts in imaging in the presence of a spin-lock radio-frequency field
A system acquires MR image data of a portion of patient anatomy associated with spin lattice relaxation time in a rotating frame using an RF (Radio Frequency) signal generator and a magnetic field gradient generator. The RF (Radio Frequency) signal generator generates RF excitation pulses in anatomy and enables subsequent acquisition of associated RF echo data. The magnetic field gradient generator generates anatomical volume select magnetic field gradients for phase encoding and readout RF data acquisition in a three dimensional (3D) anatomical volume. The RF signal generator and the gradient generator use in order, a saturation pulse, a T1 spin lattice relaxation rotating frame preparation pulse sequence and a spoiler gradient, in acquiring image data of the 3D volume showing luminance contrast associated with T1 spin lattice relaxation in a rotating frame.
METHOD AND SYSTEM FOR ANALYZING MULTI-COMPONENT MAGNETIC RESONANCE SIGNALS
Method for mapping the transverse relaxation times (T.sub.2) in a magnetic resonance imaging (MRI) scan defined over a plurality of pixels, where each pixel is associated with a multicomponent T.sub.2 (mcT.sub.2) signal, comprises: accessing a computer readable medium storing an mcT.sub.2 dictionary having a set of synthetic mcT.sub.2 signals, and selecting a subset of synthetic mcT.sub.2 signals for which correlations between the synthetic mcT.sub.2 signals and pixels in the MRI scan are highest among the set. For each of at least a portion of the pixels, a respective mcT.sub.2 scan signal is fitted to the subset to provide, a plurality of T.sub.2 values for the pixel. A T.sub.2 map of the MRI scan is generated based on the T.sub.2 values.