Patent classifications
A61B5/0263
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.
Cerebral blood flow reorganization
An implantable device includes an outer tubular member defining a longitudinal axis and a lumen. The outer tubular member includes: an outer wall portion having a plurality of first strands defining a plurality of first openings therebetween, the outer wall portion having a first porosity; and an inner baffle portion disposed within the lumen, the inner baffle portion including a plurality of second strands defining a plurality of second openings therebetween, the inner baffle portion having a second porosity that is lower than the first porosity of the outer wall portion.
Measuring blood vessel characteristics with MRI
Aspects of the subject disclosure may include, for example, obtaining first magnetic resonance imaging (MRI) data of a subject, wherein the first MRI data is obtained during a first scan of a subject, wherein the first scan has a first diffusion sampling time, and wherein the first diffusion sampling time is selected in order to facilitate use of the first MRI data to determine a first Intravoxel Incoherent Motion (IVIM) effective diffusion coefficient in a Stationary Random Flow (SRF) regime; obtaining second MRI data of the subject, wherein the second MRI data is obtained during a second scan of the subject, wherein the second scan has a second diffusion sampling time, wherein the second diffusion sampling time is longer than the first diffusion sampling time, and wherein the second diffusion sampling time is selected in order to facilitate use of the second MRI data to determine a second IVIM effective diffusion coefficient in a pseudodiffusion regime; determining a blood velocity value based upon the first MRI data; and determining a segment length value based upon the second MRI data. Additional embodiments are disclosed.
Coherent hemodynamics spectroscopy and model based characterization of physiological systems
A method for inferring characteristics of a physiological system includes measuring one or more physiological signals in the physiological system and inferring characteristics of the physiological system from the one or more measured physiological signals using a multiple vascular compartment hemodynamic model, the multiple vascular compartment hemodynamic model defining a relationship between the one or more measured physiological signals and the characteristics of the physiological system. When the one or more measured physiological signals include coherent oscillations at a plurality of frequencies, the method is termed coherent hemodynamics spectroscopy. The multiple vascular compartment hemodynamic model is based on an average time spent by blood in one or more of said vascular compartments and a rate constant of oxygen diffusion.
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.
IMAGING ABNORMALITIES IN VASCULAR RESPONSE
Z maps combined with a standardized stimulus in the form of a targeted arterial partial pressures of carbon dioxide provide suprisingly enhanced images for the assessment of pathological CVR. For example, the z-map assessment of patients with known steno-occlusive diseases of the cervico-cerebral vasculature showed an enhanced resolution of the presence, localization, and severity of the pathological CVR. Z-map have been found to be useful to reduce the confounding effects of test-to-test, subject-to-subject, and platform-to-platform variability for comparison of CVR images showing the importance of combining this analysis with the standardized stimulus.
Evaluation system or determination of cardiovascular function parameters
An evaluation system for determination of cardiovascular function parameters is provided. The evaluation system includes a data reading module, an image generating module, a contour determination module, an active contour module, a geometric center axis computing module, a view angle selection module and a function evaluation module. After reading cardiovascular graphic files with the data reading module, the image generating module displays 2D images or a 3D image constructed from the 2D images. Then, active contours are generated by the contour determination module and the active contour module, so as for the geometric center axis computing module to calculate geometric center axes. The view angle selection module then rotates the 3D image according to the view angle data received and modifies the 2D image files accordingly to generate plural cross-section images of the 3D image. Finally, the function evaluation module calculates evaluation parameters according to the geometric center axes. Thus, evaluation parameters can be derived from cardiovascular ultrasound images for clinical diagnosis in the evaluation of cardiovascular functions.
IMAGE PROCESSING DEVICE AND MRI APPARATUS
In one embodiment, an image processing device includes memory circuitry configured to store a program; and processing circuitry configured, by executing the program, to extract an outer wall of a tubular structure by using a fat image obtained by a water/fat separation method of magnetic resonance imaging, and generate a tubular-structure wall image in which a wall of the tubular structure is distinguished, based on the outer wall.