Abstract: A method to define a curved slab region of interest that includes vessels while maximally excluding surrounding soft tissue and bone is provided. The thickness of the curved slab is automatically adapted to the thickness of the vessel and follows the tortuous vessel(s) so that an increase in tortuousity does not result in a disproportionate increase in the region of interest required to enclose the vessel. A plurality of boundary pairs is determined in the view plane to define a vessel. Vessel-intensities are determined for each one of the boundary pairs. The boundary pairs with associated intensities define the view of the vessel in the projection plane. Context-intensity could be defined in the area surrounding the boundary pairs in the projection and/or transverse plane. The method also includes several steps that will result in a better isolation and removal of non-vessel structures and view of the vessel(s) and its(their) branches.

Abstract: A method of identifying polyps and in a medical image is provided. In a first step, a 3-dimensional model is made of the medical image that contains both polyps (if any were present in the original medical image) and folds. Next, a second 3-dimensional model of the medical image, which is a filtered version of the first model, is constructed in which folds are preserved, but polyps are minimized or eliminated. In a third step, any polyps that were contained in the medical image are identified by subtracting the second 3-dimensional model from the first 3-dimensional model. This subtraction results in a third 3-dimensional model, in which polyps are preserved but folds are minimized or eliminated. With the present inventive method, polyps may be easily and quickly identified without interference from folds.

Abstract: A nodule registration system useful for tracking lung nodules in computed tomography (CT) scans is presented. The system registers a small sphere centered on a detected nodule in one scan with another scan under a rigid transformation assumption using a fast registration scheme. The registration scheme employs very fast simulated annealing (VFSA) with constraints to maximize a tunable cross-correlation (TCC) coefficient, enabling the system to register, with minimal registration error, all nodules within their maximum diameter. The system achieves an average registration time of 10 seconds or less on a 3.06 GHz computer programmed to implement the present invention.

Abstract: Improved surface feature recognition in CT images is provided by extracting a triangulated mesh representation of the surface of interest. Shape operators are computed at each vertex of the mesh from finite differences of vertex normals. The shape operators at each vertex are smoothed according to an iterative weighted averaging procedure. Principal curvatures at each vertex are computed from the smoothed shape operators. Vertices are marked as maxima and/or minima according to the signs of the principal curvatures. Vertices marked as having the same feature type are clustered together by adjacency on the mesh to provide candidate patches. Feature scores are computed for each candidate patch and the scores are provided as output to a user or for further processing.

Abstract: Disclosed are method and apparatus for guiding a needle during an interventional radiology procedure. The target and skin entry point are pre-determined in three-dimensional medical imaging scans. The needle trajectory is defined by the target and skin entry point, which is physically marked on the skin. A dual-headed laser emitting two laser beams is positioned and aligned such that one laser beam is aimed at the skin entry point and the other laser beam is aimed at an external reference point, which is determined such that the axis of the laser beam aimed at the skin entry point is substantially collinear with the needle trajectory. The needle is inserted while maintaining the axis of the needle substantially collinear with the axis of the laser beam aimed at the skin entry point.

Abstract: A pointing light device includes a light pointer, such as a laser pointer; and an elongated pointing member detachably associated with the light pointer. The pointing member contains at least two bead-like members. Also, a method for aligning a light pointer with a predetermined medical interventional device trajectory. The method includes attaching a pointing member to an output end the light pointer to form a movable pointing light device; imaging two or more bead-like members of the pointing member to create live projection images or shadows in the live projection image; projecting at least first and second points associated with the predetermined medical interventional device trajectory onto the live projection image; and moving the pointing light device until the live projection images of the two members are aligned with corresponding ones of the projected first and second points in the live projection image.

Abstract: A method to quantify the vascular irregularity of aortoiliac arteries is provided. Inner wall and/or outer wall outlines of a vessel of interest are determined. The cross sectional area is determined for the area outlined by each outline. Using this cross sectional area a shape is selected that has substantially the same area as the outline. Subsequently, the shape is fitted to the outline. In one aspect, the irregularity index is calculated as the ratio of the outline and the outline of the fitted shape. In another aspect, the irregularity index is calculated as the ratio of at least a part of the outline and the outline of the fitted shape that corresponds to the same part of the outline. The irregularity index is visualized using a color scheme, a range of numbers, or a set of labels.

Abstract: A method of selectively removing folds in a medical image is provided. With this method, a medical image is deformed to straighten and flatten folds but not polyps, thus allowing polyps to be identified. In a first step, a 3-dimensional deformable model of the medical image is constructed. This model is set to have a high Young's modulus and a low Poisson's ratio. In a preferred embodiment, the model is a continuum surface model, preferably a quasistatic continuum finite element model. Once the model has been constructed, it is deformed such that folds are removed but polyps remain, allowing polyps to be identified.

Abstract: A detection and classification method of a shape in a medical image is provided. It is based on generating a plurality of 2-D sections through a 3-D volume in the medical image. In general, there are two steps. The first step is feature estimation to generate shape signatures for candidate volumes containing candidate shapes. The feature estimation method computes descriptors of objects or of their images. The second general step involves classification of these shape signatures for diagnosis. A classifier contains, builds and/or trains a database of descriptors for previously seen shapes, and then maps descriptors of novel images to categories corresponding to previously seen shapes or classes of shapes.

Abstract: A method that allows the quantification of the true mass of a calcium fragment located along a vessel is provided. The method is independent of the level of arterial contrast enhancement, does not require protocol-specific or scanner-specific calibration scans, and allows a detailed analysis of calcium distribution patterns. For each identified calcium fragment, the average intensity and volume is determined as a function of a plurality of intensity thresholds. Using these determined values brightness volume products are calculated for each of the plurality of intensity thresholds. The mass of a calcium segment is subsequently obtained from the calculated brightness volume products extrapolated at zero intensity and reference calcium parameters. The mass and volume of the calcium fragments could be visualized with respect to a vessel in a computer display.

Abstract: A method to quantify the radial endoluminal irregularity of aortoiliac arteries is provided. Radial endoluminal outlines of a vessel of interest are determined. The cross sectional area is determined for the area outlined by each endoluminal outline. Using this cross sectional area a shape is selected that has substantially the same area as the endoluminal outline. Subsequently, the shape is fitted to the endoluminal outline. In one aspect, the irregularity index is calculated as the ratio of the endoluminal outline and the outline of the fitted shape. In another aspect, the irregularity index is calculated as the ratio of at least a part of the endoluminal outline and the outline of the fitted shape that corresponds to the same part of the endoluminal outline. The irregularity index is visualized using a color scheme, a range of numbers, or a set of labels.

Abstract: An improved method is disclosed for imaging in an interventional medical procedure that is more advanced than a conventional 2D image processing application and less restrictive than a 3D reconstruction image processing application. In contrast to the prior art 2D imaging application in which a single 2D image is acquired, the inventive method acquires and stores a set of 2D anatomical images while rotating a C-arm/X-ray source using a single injection of contrast agent. In lieu of performing a 3D reconstruction, the multiplicity of anatomical views provided by the set of 2D anatomical images adequately serve as a visual “rotatable roadmap” to perform classical 2D-roadmapping navigation. The “rotatable roadmap” assists a user to locate an ideal working view of the patient's region of operative interest.

Abstract: A Learning Enhanced Simulated Annealing (LESA) method is provided. Based on a Simulated Annealing (SA) framework, this method adds a Knowledge Base (KB) initialized at the beginning of the search and updated at each iteration, which memorizes a portion of the search history and guides the further search through a KB trial generator. The basic idea of LESA is that its search history is stored in a KB, and a KB trial generator extracts information from it and uses it to generate a new trial. The next move of the search is the weighted sum of the trial generated by the KB trial generator and the trial generated by the usual SA trial generator. The knowledge base is then updated after each search iteration.

Abstract: A method to detect and classify a structure of interest in a medical image is provided to enable high specificity without sacrificing the sensitivity of detection. The method is based on representing changes in three-dimensional image data with a vector field, characterizing the topology of this vector field and using the characterized topology of the vector field for classification of a structure of interest. The method could be used as a stand-alone method or as a post-processing method to enhance and classify outputs of a high-sensitivity low-specificity method to eliminate false positives.

Abstract: Certain embodiments of the present invention provide systems and methods for correlating an acquired image with an historical image. Certain embodiments include registering an acquired image and at least one historical image according to a coordinate system, applying a metric to the acquired image and each of the historical image(s), and identifying a correlation between the acquired image and one of the historical image(s) based on the metric. Certain embodiments further include storing the correlation between the acquired image and an historical image for automatic linking of the acquired image and the historical image upon display. In certain embodiments, the acquired image and the historical image may be displayed based on the correlation. In certain embodiments, the acquired image and the historical image may be automatically linked based on the correlation. In certain embodiments, the metric analyzes the acquired image and at least one historical image based on anatomy.

Abstract: An automatic method for the registration of prone and supine computed tomographic colonography data is provided. The method improves the radiologist's overall interpretation efficiency as well as provides a basis for combining supine/prone computer-aided detection results automatically. The method includes determining (centralized) paths or axes of the colon from which relatively stationary points of the colon are matched for both supine and prone positions. Stretching and/or shrinking of either the supine or prone path perform registration of these points. The matching and registration occurs in an iterative and recursive manner and is considered finished based on one or more decision criteria.

Abstract: Certain embodiments of the present invention provide a system and method for automatic image post processing in a healthcare environment. In an embodiment, an automatic post processing image generation system includes at least one user interface, which is adapted to display at least one image on an image viewer and perform image post processing using at least one image post processing application. The system also includes at least one storage server capable of storing user data, wherein the user data includes at least one image and/or at least one post processing parameter. In addition, the system includes a post processing engine for automatically generating and displaying a current post processed image based on at least one image registration technique to correlate the at least one post processing parameter of a related previous post processed image with a current image.

Abstract: A method to define a curved slab region of interest that includes vessels while maximally excluding surrounding soft tissue and bone is provided. The thickness of the curved slab is automatically adapted to the thickness of the vessel and follows the tortuous vessel(s) so that an increase in tortuousity does not result in a disproportionate increase in the region of interest required to enclose the vessel. A plurality of boundary pairs is determined in the view plane to define a vessel. Vessel-intensities are determined for each one of the boundary pairs. The boundary pairs with associated intensities define the view of the vessel in the projection plane. Context-intensity could be defined in the area surrounding the boundary pairs in the projection and/or transverse plane. The method also includes several steps that will result in a better boundary outline and view of the vessel.

Abstract: A computer-implemented method for determining and characterizing, which portions or shapes of a medical image correspond to a shape of interest is provided. A candidate shape is obtained after which a visible surface is computed adjacent to this candidate shape. A visible surface includes one or more portions of the medical image that are visible by the candidate shape. Once the visible surface is determined, parameters of the visible surface are computed. Then the method further includes the step of determining whether the candidate shape corresponds to a shape of interest. The method further includes the step of computing features of the candidate shape and/or classifying the candidate shape. The advantage of the computer-implemented method is that it provides a high detection specificity, i.e. reducing false positives, without sacrificing sensitivity of the detection of a shape of interest.

Abstract: A method for identifying a arteries and veins in a medical image is provided. A start point and endpoints of branches of a segmented tubular tree are identified. Distance maps for each of the endpoints relative to the startpoint are created. Then voxels in between the furthest of the endpoints and the startpoint are identified. This last step is iterated for the subsequent furthest of the endpoints. For each set of identified voxels parameters are identified. Examples of such parameters are cross sectional areas of the branches. The parameters for at least one each set of identified voxels are then used to anatomically label branches the segmented tubular tree, optionally with position information obtained from the image.