Abstract: A method for automatically localizing left ventricle in medical image data includes acquiring a sequence of three-dimensional medical images spanning a cardiac cycle. Each of the images includes a plurality of two-dimensional image slices, one of which is defined as a template slice. The template slice of each medical image of the sequence is automatically cropped to include the heart and a margin around the heart based on temporal variations between pixels of the template slice throughout the sequence of medical images. The template slice of each medical image of the sequence is automatically contoured to determine the endo-cardial and epi-cardial boundaries for at least the end-diastolic and end-systolic phases. Localization information is generated for the left ventricle based on the determined endo-cardial and epi-cardial boundaries for at least the end-diastolic and end-systolic phases.

Abstract: A reconstructed image is rendered from a set of MRI data by first estimating an image with an area which does not contain artifacts or has an artifact with a relative small magnitude. Corresponding data elements in the estimated image and a trial image are processed, for instance by multiplication, to generate an intermediate data set. The intermediate data set is transformed and minimized iteratively to generate a reconstructed image that is free or substantially free of artifacts. In one embodiment a Karhunen-Loeve Transform (KLT) is used. A sparsifying transformation may be applied to generate the reconstructed image. The sparsifying transformation may be also not be applied.

Abstract: A method and system for automated view planning for cardiac magnetic resonance imaging (MRI) acquisition is disclosed. The method and system automatically generate a full scan prescription using a single 3D MRI volume. The left ventricle (LV) is segmented in the 3D MRI volume. Cardiac landmarks are detected in the automatically prescribed slices. A full scan prescription, including a short axis stack and 2-chamber, 3-chamber, and 4-chamber views, is automatically generated based on cardiac anchors provided by the segmented left ventricle and the detected cardiac landmarks in the 3D MRI volume.

Abstract: A method for symmetric and inverse-consistent registration of a pair of digital images includes calculating a first update of a forward transformation of a first digital image to a second digital image from a previous update of the forward transformation and a gradient of a cost function of the first and second digital images, calculating a first update of a backward transformation of the second digital image to the first digital image from an inverse of the first update of the forward transformation, calculating a second update of the backward transformation from first update of the backward transformation and the gradient of a cost function of the second and first digital images, and calculating a second update of the forward transformation from an inverse of the second update of the backward transformation.

Abstract: A method and system for retrospective image combination for free-breathing magnetic resonance (MR) images is disclose. A free-breathing cardiac MR image acquisition including a plurality of frames is received. A key frame is selected of the plurality of frames. A deformation field for each frame to register each frame with the key frame. A weight is determined for each pixel in each frame based on the deformation field for each frame under a minimum total deformation constraint. A combination image is then generated as a weighted average of the frames using the weight determined for each pixel in each frame.

Abstract: A method for tracking a contour in cardiac phase contrast flow magnetic resonance (MR) images includes estimating a global translation of a contour in a reference image in a time sequence of cardiac phase contrast flow MR images to a contour in a current image in the time sequence of images by finding a 2-dimensional translation vector that maximizes a similarity function of the contour in the reference image and the current image calculated over a bounding rectangle containing the contour in the reference image, estimating an affine transformation of the contour in the reference image to the contour in the current image, and performing a constrained local deformation of the contour in the current image.

Abstract: A method for identifying a region of interest within a time sequence of images includes acquiring a time sequence of images comprising a plurality of image frames. Image segmentation is performed to segment a region of interest (ROI) from within each of the plurality of image frames of the time sequence of images. Manual edits are received for the ROI within one or more of the plurality of image frames. The manual edits are propagated to other image frames of the plurality of images. An extent to which each of the manual edits are propagated to other image frames is dependent upon a transformation function or deformation field used to propagate the manual edits and a weighing factor that is influenced by a distance in time between the other image frames and the frames that have been manually edited.

Abstract: A method for clinical parameter derivation and adaptive flow acquisition within a sequence of magnetic resonance images includes commencing an acquisition of a sequence of images. One or more landmarks are automatically detected from within one or more images of the sequence of images. The detected one or more landmarks are propagated across subsequent images of the sequence of images. A plane is fitted to the propagation of landmarks. The positions of landmarks or alternatively the position of the fitted plane within the sequence of images is used for derivation of clinical parameters such as tissue velocities and/or performing adaptive flow acquisitions to measure blood flow properties.

Abstract: A method (100) of processing myocardial MR perfusion images that corrects imaging errors arising from myocardial motion and B-1 field inhomogeneity (115-135); segments the myocardium images (140, 145); and calculates perfusion measures that enable analysis of the segmented myocardium images (150).

Abstract: A method for correcting the background phase in magnetic resonance phase contrast flow images includes providing a time series of velocity encoded magnetic resonance images of a patient, where the time series of velocity encoded images comprises for each time point a phase contrast image where a pixel intensity is proportional to a flow velocity, measuring a change of intensity for each pixel over the time series of phase contrast images, identifying pixels with a low measure of temporal change as stationary pixels, and calculating a correction field for the stationary pixels, where the correction field represents a background phase to be subtracted from the phase contrast image.

Abstract: A method for automatically generating a myocardial perfusion map from a sequence of magnetic resonance (MR) images includes determining a region of interest (ROI) in a reference frame selected from a time series of myocardial perfusion MR image slices, registering each image slice in the time series of slices to the reference frame to obtain a series of registered ROIs, and using the series of registered ROIs to segment endo- and epi-cardial boundaries of a myocardium in the ROI.

Abstract: In a method for image data acquisition of a region of interest in a subject with a magnetic resonance device, wherein, to establish the field of view, a minimal geometric shape encompassing the subject to be acquired and/or the surface of the subject is determined automatically from previously acquired localizer exposures as aliasing information for each exposure, at least one slice plane is determined for the acquisition of the region, and the phase coding direction and/or the extent of the field of view in the phase coding direction is determined for every slice plane using the aliasing information.

Abstract: A method and system for vessel enhancement and artifact reduction in a 3D time-of-flight (TOF) magnetic resonance (MR) angiography brain image. An intensity-based threshold is used to extract structures of interest in the brain image. Vessels are isolated in the structures of interest by filtering the structures based on a vesselness measure. The vessels are then enhanced by multiplying the filtered image by a coefficient map based on intensities of the original brain image. The scalp is detected in the enhanced image, and the scalp is removed from the enhanced image to generate a noise-reduce enhanced image.

Abstract: A method for automatically selecting a number of Gaussian modes for segmentation of a cardiac magnetic resonance (MR) image, including: identifying a left ventricle (LV) in a cardiac MR image slice; quantifying the LV blood pool; obtaining a mask for the LV blood pool; generating a ring mask for a myocardium of the LV from the LV blood pool mask; fitting three Gaussian modes to a histogram of the image slice to obtain a corresponding homogeneity image for the myocardium; computing a quality of fitting (QOF) measure for the three Gaussian modes based on the corresponding homogeneity image; repeating the fitting and computing steps for four and five Gaussian modes; and selecting the homogeneity image of the number of Gaussian modes with the largest QOF measure as the homogeneity image for processing.

Abstract: Method of correcting cardiac perfusion MR imaging for inhomogeneities (430) caused by non-uniform receiver coil fields using proton density weighted images (410) and B-Spline Free-Form Deformation (425).

Abstract: The invention relates to a method for determining midpoint coordinates of an image of a point-symmetrical structure stored in a volume data record, comprising: extracting a partial volume data record from the volume data record which contains the image of the point-symmetrical structure, selecting a set of points whose coordinates lie in the partial volume data record, determining a measure for each point of the set wherein the measure for each of the points of the set characterizes in each case the symmetry of the partial volume data record in relation to this point, selecting a point as a midpoint of the point-symmetrical structure that point of the set in relation to which the partial volume data record has the greatest symmetry on the basis of the previously determined measures, and storing the coordinates of the midpoint in a computer unit.

Abstract: In a method for representation of the heart in a magnetic resonance system at least one MR overview image of the heart is acquired. An image plane with a predetermined position relative to the magnetic resonance system is selected for this overview image. The acquired MR overview image is displayed and a number of marking points are established in the displayed overview image. Further image planes for representation of the heart are calculated using some of the established marking points. Further MR images are acquired in the calculated image planes.

Abstract: A system dynamically improves quality of medical images using at least one processing device including an image analyzer, a correction processor and a message generator. The image analyzer automatically parses and analyzes data representing an image of a particular anatomical feature of a patient acquired by a medical image acquisition device to identify defects in the image by examining the data representing the image for predetermined patterns associated with image defects. The correction processor uses a predetermined information map associating image defects with corresponding corrective image acquisition parameters to determine corrected image acquisition parameters for use in re-acquiring an image using the image acquisition device in response to an identified defect. The message generator generates a message for presentation to a user indicating an identified defect and suggesting use of the corrected image acquisition parameters for re-acquiring an image.

Abstract: A method of deriving blood flow parameters from a moving three-dimensional (3D) model of a blood vessel includes determining a reference vascular cross-sectional plane through a location of a lumen in a moving 3D model of the blood vessel at one time within the model, determining a plurality of target vascular cross-sectional planes at multiple times via temporal tracking of the reference plane based on a displacement field, determining a plurality of contours based on an intersection of the target vascular cross-sectional planes with the moving 3D vessel model at multiple times within the model, and determining a blood flow parameter of the vessel from intersections of each contour of a given one of the times with a phase contrast magnetic resonance (PC-MRI) image of the blood vessel from the corresponding time.

Abstract: A method for cardiac segmentation in magnetic resonance (MR) cine data, includes providing a time series of 3D cardiac MR images acquired at a plurality of phases over at least one cardiac cycle, in which each 3D image includes a plurality of 2D slices, and a heart and blood pool has been detected in each image. Gray scales of each image are analyzed to compute histograms of the blood pool and myocardium. Non-rigid registration deformation fields are calculated to register a selected image slice with corresponding slices in each phase. Endocardium and epicardium gradients are calculated for one phase of the selected image slice. Contours for the endocardium and epicardium are computed from the gradients in the one phase, and the endocardium and epicardium contours are recovered in all phases of the selected image slice. The recovered endocardium and epicardium contours segment the heart in the selected image slice.