Abstract: In a method for surface contouring of a three-dimensional image of an object a set of planes is placed through the three-dimensional image, and the contours that are imaged in each of the planes of the first set of planes, and that are associated with the surface contour of the three-dimensional image, are determined. The contours are subsequently combined into a surface grid associated with the surface contour of the three-dimensional image.

Abstract: A method and system is presented for tracking patient motion in image guided surgery, using skeletal reference structures instead of fiducial markers. A non-rigid 2D/3D image registration is performed between pre-operative 3D scan data and intra-operative 2D images. The CT numbers are modified to compensate for the difference between the ratio of bone-to-tissue attenuation at the CT scan energy level, and the x-ray projection energy level. DRRs are generated from the modified CT numbers. An ROI, within which the image registration is restricted, is defined within the DRRs by calculating a modified Shannon entropy for each image, and seeking the region in which the image entropy is maximized. The DRRs and 2D images are enhanced by applying a top hat filter to increase the visibility of the skeletal structures. The 2D/3D transformation parameters are determined by generating a full motion field that accounts for non-rigid motions and deformations.

Abstract: The invention relates to a method for analyzing perfusion images, in particular MR pertbsion images, of a human or animal organ including the steps of: (a) defining at least one contour of the organ, and (b) establishing at least one perfusion parameter of a region of interest of said organ within a boundary defined by the at least one contour, whereby steps (a) and (b) are repeated in a series of iterative steps wherein for each subsequent iterative step the definition of the at least one contour in step (a) is varied, and the series of iterative steps is terminated after reaching an optimal value for the at least one perfusion parameter in step (b).

Abstract: A technique is provided for segmenting a structure of interest from a volume dataset. The technique identifies regions of the structure using templates having characteristics of the structure of interest. The identified regions may then undergo a constrained growth process using dynamic constraints that may vary based on local statistics associated with the identified structure regions. Edges within the volume may be determined using gradient data determined by evaluating the strongest gradient between each pixel and all adjacent pixels. The edge data may be used to prevent the constrained growing process from exceeding the boundaries of the structure of interest.

Abstract: A segmented radial spatial light modulator has an active optic area comprising a plurality of radially extending active optic modulators disposed at various angular orientations with respect to a central axis. The segmented radial spatial light modulator is used in separating and isolating portions of Fourier transform optic patterns from images for characterization of images by shape for recording, storing, retrieving, searching, and comparison to other images for matches and near matches. The images can be ghosted to increase optical power in the Fourier transform optic pattern without adding new shape content and for grading comparisons to other image shape characteristics for identifying near matches in addition to matches.

Abstract: A method of separating and collating mammogram records, the method including the step of providing and scanning a separator film having identifiable features which when scanned identify the film as a separator film, thereby assisting in the separation of mammograms of different patients. A separator film for use with a mammogram workstation the film having at least one identifiable characteristic recognizable by the workstation's processing means so that the film is identified as a separator film separating mammograms of different patients. A workstation system for collating radiological film mammograms which includes a scanner which digitizes radiological film mammograms and scans a separator film carrying identifiable features for identifying the film as a separator film usable to separate mammograms of different patients.

Abstract: The same subject can be accurately aligned for effective interpretation of two observation images representing a change in the subject and not adjacent to each other in three or more images arranged in temporal order of the change. The subject in one of the observation images is aligned to the subject in a transitional image adjacent to the observation image, and an aligned image is generated. The same procedure is repeated between the previous aligned image and a transitional image adjacent to the previous transitional image to generate another aligned image. A final aligned image is generated by aligning the subject in the observation image to the subject in a reference image. This procedure is carried out for the other observation image and a final aligned image is also generated by alignment to the reference image. A diagnostician compares the two final aligned images.

Abstract: An algorithm is quickly scans a digital image volume to detect density nodules. A first stage is based on a transform to quickly highlight regions requiring further processing. The first stage operates with somewhat lower sensitivity than is possible with more detailed analyses, but operates to highlight regions for further analysis and processing. The transform dynamically adapts to various nodule sizes through the use of radial zones. A second stage uses a detailed gradient distribution analysis that only operates on voxels that pass a threshold of the first stage.