摘要:
Described are computer-based methods and apparatuses, including computer program products, for automatic image segmentation using contour propagation. A path metric of a candidate piece of a contour in a cross-sectional image is calculated to generate a three dimensional model using a plurality of cross-sectional images of an object. Data indicative of the cross-sectional image is stored. A cost of each of a plurality of pixels associated with the candidate piece is calculated using the data, wherein the cost is representative of a likelihood the pixel is on the contour and the cost is based on one or more templates. An orientation change value is calculated for each of the plurality of pixels associated with the candidate piece based on an initial pixel of the candidate piece and the pixel. A ratio of pixels is calculated. The path metric of the candidate piece of the contour is stored, the value of the stored path metric being based on the calculated cost, the calculated orientation change value, and the calculated ratio.
摘要:
Described are computer-based methods and apparatuses, including computer program products, for automatic image segmentation using contour propagation. A path metric of a candidate piece of a contour in a cross-sectional image is calculated to generate a three dimensional model using a plurality of cross-sectional images of an object. Data indicative of the cross-sectional image is stored. A cost of each of a plurality of pixels associated with the candidate piece is calculated using the data, wherein the cost is representative of a likelihood the pixel is on the contour and the cost is based on one or more templates. An orientation change value is calculated for each of the plurality of pixels associated with the candidate piece based on an initial pixel of the candidate piece and the pixel. A ratio of pixels is calculated. The path metric of the candidate piece of the contour is stored, the value of the stored path metric being based on the calculated cost, the calculated orientation change value, and the calculated ratio.
摘要:
A method and apparatus for reconstructing a surface shape of an object having contour lines, includes assigning points to each contour line. A first triangulation scheme is performed with respect to respective points on two adjacently-positioned contour lines, to determine a first surface shape for a portion of the object corresponding to the two contour lines. The first surface shape is checked to determine if the first surface shape is in error. If the first surface shape is not in error, the first surface shape is outputted for the portion of the object as determined by the first triangulation scheme, as a reconstructed surface shape for that portion of the object. If the first surface shape is in error, a second triangulation scheme is performed with respect to the respective points on the two contour lines, to determine a second surface shape for that portion of the object, and the second surface shape is outputted for that portion of the object as determined by the second triangulation scheme, as a reconstructed surface shape.
摘要:
A surgical planning method is provided. A representation of a bone of a joint is created. The joint is moved to a first position. A first point corresponding to a first location in the joint is identified when the joint is in the first position. The joint is moved to a second position. A second point corresponding to a second location in the joint is identified, when the joint is in the second position. Bone preparation for implanting an implant on the bone is planned based at least in part on the first and second points.
摘要:
A volume image memory (24) stores an electronic image representation of a volumetric region, such as the volumetric region examinedby a medical diagnostic scanner (10). A sub-region of interest of the volume is selected (30) and the surface of the selected region or object of interest is divided into triangular surface regions with a triangular surface processor (38). A vertex merging processor (40) examines the triangles to locate vertices spaced by less than a preselected minimum. Vertices closer than the preselected minimum are replaced with a vertex at a median position merging the triangle into adjacent triangles. A vertex removal processor (50) identifies groups of triangles having a common vertex (V.sub.c) that form a pyramid. The surface normals (N) of the triangles which define the pyramid are examined to determine whether they are within a preselected deviation of parallel. The altitude of the pyramid, i.e., a distance between the common vertex and an average plane (P.sub.avg) of the triangles is compared with a preselected maximum height. Triangular groups which pass the surface normal and maximum height tests have their common vertex removed (72) and are retriangulated (74) to reduce the number of triangles by two. An image processor (84) converts the relative angles of viewing and illumination directions relative to the surface normal of each visible triangle into a corresponding image value, e.g. gray scale, for display on a video monitor (34).
摘要:
A system and method for providing computer assistance for performing a medical procedure provides a graphical user interface to guide and/or assist a user, for example a surgeon, performing the medical procedure, whether surgical or non-surgical. The computer-assisted system comprises a software application that may be used for a medical procedure.
摘要:
A surgical apparatus includes a surgical device, configured to be manipulated by a user to perform a procedure on a patient, and a computer system. The computer system is programmed to create a representation of an anatomy of a patient; to associate the anatomy and a surgical device with the representation of the anatomy; to manipulate the surgical device to perform a procedure on a patient by moving a portion of the surgical device in a region of the anatomy; to control the surgical device to provide at least one of haptic guidance and a limit on manipulation of the surgical device, based on a relationship between the representation of the anatomy and at least one of a position, an orientation, a velocity, and an acceleration of a portion of the surgical device; and to adjust the representation of the anatomy in response to movement of the anatomy during the procedure.
摘要:
In accordance with an embodiment of the present invention, an image guided interventional system enables registration of a patient, preferably automatically and without an explicit patient registration step, to newly acquired images as the patient is moved out of the imager. Only one set of images has to be taken. The position of the needle or other instrument is tracked using a tracking system and its position continually displayed and updated with respect to the images. Therefore, there is no need to take additional images for purposes of tracking progress of an instrument being inserted into a patient. Avoiding additional scans saves time and reduces exposure of the patient to radiation.
摘要:
A method of mapping a chosen point in real space to its corresponding location in image space includes obtaining a diagnostic medical image of a subject including multiple rigid objects, and individually computing separate transforms which register each of the rigid objects in real space with their corresponding locations in image space. After choosing a target point in real space, the target point is mapped to image space using a designated transform. A number of the rigid objects are selected which are closest to the target point in image space, and an interpolated transform is generated from the separate transforms which correspond to the selected rigid objects. The target point is re-mapped in image space using the interpolated transform, and the interpolated transform is set as the designated transform for subsequent mappings.
摘要:
A SPECT camera system has detector heads (14a, 14b, 14c) each having a collimator (18) facing toward an examination region (10). The detectors receive emission radiation from a radioisotope injected into a subject in the examination region and, preferably, also receive transmission radiation from a transmission source (20) disposed across the examination region. The detectors rotate around the subject through a plurality of projection angles. The detectors generate projection views from the received radiation for each projection angle. The projection views are stored in a projection view memory (26). A reconstruction processor (38) reconstructs the projection views into a volumetric image representation that is stored in a volumetric image memory (40). A reprojector (42) reprojects the volumetric image and volume of interest along each projection angle producing a set of reprojection views and regions of interest. A view comparator (50) compares each corresponding projection and reprojected view within the region of interest along a common projection direction. A translator (52) translates or offsets each projection view in accordance with the comparison to produce a corrected or shifted projection view. The corrected projection views are then reconstructed to produce a motion corrected volumetric image representation. This procedure may be iterated to optimize the motion correction.