General Electric Company

Other

The Henry M. Jackson Foundation for the Advancement of Military Medicine Inc.

Massachusetts General Hospital Corporation

Uniformed Services University of Health Sciences

United States of America Department of Defense

Ge Medical Systems Global Technology Company, LLC

Vincent B Ho

Thomas K F Foo

Ting Song

Rebecca A McCann

Thomas Kwok-Fah Foo

Matthew A Bernstein

Thomas K Foo

Steven D Wolff

Ek Tsoon Tan

Manojkumar Saranathan

Ehud J Schmidt

Maggie M Fung

Godtfred Holmvang

Micah D Schmidt

Thomas Kf Foo

Rebecca Ann Mccann

Systems and methods for Magnetic Resonance Angiography (MRI) are provided. One method includes obtaining Magnetic Resonance (MR) velocity data and determining a distance map for one or more vessels to define a distance path. The method also includes calculating, using the MR velocity data, at a plurality of time intervals and for a plurality of pixels (i) a distance traveled during a current time interval as a current distance traveled, wherein a total distance traveled is incremented by the current distance traveled and (ii) a bolus signal using a bolus signal profile, the distance path and total distance traveled, wherein a current time interval is incremented by a defined time step.

Systems and methods for magnetic resonance angiography

A system and method for center point trajectory mapping includes a computer readable storage medium having stored thereon a computer program comprises instructions, which when executed by a computer, cause the computer to acquire a first plurality of images, each image comprising a masked portion. The instructions also cause the computer to locate a center point of the masked portion in each of the plurality of images and to plot a map based on variances in position of the center points from each other. The instructions further cause the computer to display the map on a display.

System and method for center point trajectory mapping

A computer implemented method of mapping of multiple regional center point trajectory movements of cavity walls is provided in which images are acquired and a region-of-interest is identified in each of the images. The region-of-interest is divided into a plurality of distinct regions and a regional center point for each of the regions is located in the images. For each regional center point, a center point trajectory is determined based on variances in position of the center points from each other in the images. The center point trajectory of each regional center point is decomposed into radial and circumferential components so as to isolate radial component of the center point trajectory for each regional center point in each of the images and radial motion versus time curves are displayed for each regional center point based on the determined radial component for each regional center point in each of the images.

System and method for multi-segment center point trajectory mapping

A system and method for MR imaging includes a computer programmed to determine first and second view-ordering sequences. The first and second view-ordering sequences comprise values corresponding to respective views of first and second k-space data sets, respectively, wherein the values corresponding to a central view of each the first and second k-space data sets are positioned such that acquisition of k-space data in each central view is acquired from a first and second anatomical region, respectively, as a contrast agent passes therethrough. The positions of the values corresponding to the central views of the first and second k-space data sets within the respective sequences are different. The computer is further programmed to acquire MR data according to the first and second view-ordering sequences over a series of cardiac cycles to fill data in the first and second k-space data sets, respectively.

Method and apparatus for contrast inflow dynamic MR angiography

Methods for improving spatial and/or temporal resolution of digital images and for improving image data transmission by a novel technique&#x2014;back pixelation, which involves data processing and reconstruction of overlaid images from multiple acquisition or multiple sampling. The back pixelation technique may be used for image data acquisition and transmission; it may be applied prospectively or retrospectively. In particular, the methods of this invention may be used in reducing the pixel size of a two-dimensional image or the voxel size of a three dimensional image; producing a two- or three-dimensional image from a multiplicity of images acquired from an object which are capable of overlaying one another by an increment; producing and transmitting a two- or three-dimensional image by multiple acquisitions according to an acquisition matrix; or transmitting a two- or three-dimensional image by reducing or decomposing the image to a plurality of image data packets and transmitting the same. The multiple acquisitions may be arranged by a predetermined temporal schedule. These methods may be advantageously applied in medical imaging, movies and video games, teleimage, and any other areas that involve digital image acquisition, processing, and transmission.

Pixelation reconstruction for image resolution and image data transmission

The present invention includes a method and apparatus for high sensitivity whole body scanning using MR imaging. The invention includes acquiring MR data as the patient moves through the iso-center of the magnet while providing interactive control for the operator to change scan parameters and table motion and direction. The technique allows efficient whole body scanning for fast screening of abnormalities while allowing operator control during the screening process to interrupt table motion and redirect the speed and direction of the table while also allowing control over the acquisition plane, number of sections imaged, inter-section spacing, and the scan location.

Whole body MRI scanning with moving table and interactive control

A method and apparatus is disclosed in which a two-tiered approach is taken to first grade a patient to identify the presence of any suspected stenosis, and then a second step is used to acquire more detailed information to grade the stenosis. The invention includes performing a screening study by acquiring a first MR image having a low resolution to scan a suspected stenosis region. After analyzing the first MR image to identify a suspected stenosis within the suspected stenosis region, a more detailed study is performed by acquiring a second MR image having a higher resolution than the first MR image to scan the identified suspected stenosis. If no lesions, or stenotic vessels, are identified after the first MR image, the second MR image need not be obtained. Since the first MR image is designed to be more sensitive to the detection of such stenosis, by increasing the conspicuity of the lesions, and using a fast acquisition sequence, this two-tiered approach increases the efficiency for accurate coronary artery stenosis detection and assessment.

Method and apparatus for efficient stenosis identification and assessment using MR imaging

A system and method for optimally imaging the peripheral vasculature is disclosed which includes defining a given number of scan stations along a patient's peripheral vasculature and initially injecting a relatively small amount of contrast agent into the patient to pass a test bolus through the patient's peripheral vasculature, and thereafter tracking the test bolus through the patient and adjusting the patient on a moveable table within the MR imaging device from one scan station to a next station to determine a maximum travel time that the test bolus takes to travel through each of the given number of scan stations. Additional contrast agent is then injected into the patient to pass an exam bolus through the patient's peripheral vasculature, and using the test bolus travel time, MR data can be acquired from each scan station while it is known that the exam bolus is present in that station to optimize image resolution. Initially, central k-space data is acquired for each scan station, and if time permits, the higher spatial frequency k-space data can be acquired. Otherwise, once the central k-space data is acquired for each station, the patient table is adjusted to the scan stations that require additional data acquisition. Similarly, if there is time remaining after all MR data is acquired for a particular scan station, the patient table can be moved to a previous scan station to acquire additional data in that station before moving to a subsequent scan station to acquire the central k-space data when the exam bolus arrives in that particular scan station.

Optimal imaging of the peripheral vasculature with test bolus tracking

A method and apparatus are disclosed for creating peripheral MR angiographic images and performing an MRA examination using an intravascular contrast agent in which MR data acquisition is optimized in the most distal stations in a multi-station acquisition. The technique includes administering a contrast agent into the blood stream of the patient, acquiring low spatial resolution MR images of the arterial vasculature, and tracking the passage of the contrast agent through the patient. The patient table is moved in response to the tracking. The technique continues to acquire low spatial resolution images at each of the proximal stations until the most distal station is reached where a high spatial resolution image data set is then acquired of preferentially arterial vascular structures. Higher spatial resolution images are then acquired in the proximal stations.

Method for optimal imaging of the peripheral vasculature emphasizing distal arterial visualization in a multi-station examination

A system and method are disclosed that use the steady-state free precessing (SSFP) technique for MR imaging to allow the acquisition of MR angiography images in which the acquisition is not time dependent upon the first passage of a contrast agent. The technique includes applying a pulse sequence with refocusing S signals from a train of RF pulses to a desired field-of-view (FOV) in a patient in which a contrast bolus has been injected. An SSFP image of the desired FOV is acquired, together with an S SSFP mask image of the desired FOV. The S SSFP mask image is subtracted from the SSFP image in order to reconstruct an image with improved visualization of the arterial and venous structures and reduce mis-registration artifacts.

Method and apparatus using post contrast-enhanced steady-state free precession in MR imaging

Method and apparatus for optimal imaging of the peripheral vasculature

A method and apparatus is disclosed to initially screen a patient's peripheral arterial vasculature for lesions, or stenotic vessels, using MR technology, and then grading the severity of any located stenosis. The invention includes tracking the passage of a contrast agent bolus through a patient, while acquiring a series of first MR images having low resolution. This initial examination uses flow sensitive bi-polar gradient waveforms with a gradient echo imaging pulse sequence to increase the sensitivity to lesion detectability. The bi-polar gradients generate a broad distribution of velocities in a large voxel. Relevant stenoses present in a voxel will result in intra-voxel flow dephasing in voxels immediate to and distal to the stenosis. After identifying a stenosis, a second MR image, having a higher resolution than the first, is used to grade the stenosis.

Method and apparatus for efficient stenosis identification in peripheral arterial vasculature using MR imaging

A method and apparatus is disclosed to rapidly assess the severity of a stenosis using MR technology. The invention includes identifying a suspected stenotic vessel and applying a phase contrast pulse sequence to the stenotic vessel in which the MR operator is allowed to control the amplitude and direction of the flow encoding gradient. Peak flow velocity is determined in the suspected stenotic vessel by correlating the flow encoding gradient with the onset of flow velocity aliasing. In a preferred embodiment, the invention utilizes a 2D fast gradient echo pulse sequence having flow sensitizing bipolar gradient waveforms. The resulting flow sensitizing gradients are substantially coincident in time, thereby allowing rotation of the resultant flow sensitizing gradient direction. The amplitude of the flow encoding gradient is increased until the observance of flow related aliasing. Once flow related aliasing is observed, the velocity encoding (VENC) value is recorded and used as the indicator of peak flow velocity in the suspected stenotic vessel. The process can be repeated along the suspected stenosis vessel to isolate and assess the severity of the stenosis by comparing the peak flow velocity VENC values obtained at various locations along the suspected stenosis.

Method and apparatus for rapid assessment of stenosis severity

A method of peripheral MR angiography is provided for imaging an artery or other vessel, wherein the vessel is of such length that MR data must be acquired at each of a plurality of scan stations spaced along the vessel. In accordance with the method, a contrast agent is intravenously injected, in order to provide a bolus which successively flows to each of the scan stations. After acquiring an initial subset of the MR data associated with a given scan station, the bolus is tracked to determine whether it has arrived at the next-following scan station. If so, at least some of the MR data associated with the next scan station are then acquired. However, if it is found that the bolus has not yet arrived at the next scan station, acquisition of further data at the given scan station is continued.

Growing community of inventors

North Bethesda, MD, United States of America

Vincent B Ho