Abstract: A method of generating a synthesized digital projection image, executed at least in part by a computer, acquires x-ray projection images at corresponding acquisition angles, and reconstructs a first volume image. Forward projection generates a preceding forward projection image at a first acquisition angle; a following forward projection image at an adjacent second acquisition angle; and an intermediate forward projection image for an intermediate angle. A synthesized projection image is formed by identifying a candidate patch of pixels from the intermediate forward projection image, matching a first patch of pixels from the preceding forward projection image and identifying a corresponding first acquired patch of pixels from the first acquired x-ray projection image, matching a second patch of pixels from the following forward projection image and matching a second acquired patch of pixels from the forward projection image. The first and second acquired patches are combined.

Abstract: A method for reducing metal artifacts in a volume radiographic image reconstructs a first 3-D-image using measured projection images and forms a 3-D image metal mask that contains metal voxels. For each measured projection image, a projection metal mask is a projection of the 3-D image metal mask. A 3-D prior image contains voxels within the 3-D image metal mask. Voxel values of the first 3-D image outside the 3-D image metal mask are replaced with a value representative of air or soft tissue. Non-metal voxels of the 3-D prior image are modified according to a difference between a pixel value related to the nonmetal voxel and the corresponding pixel value in a calculated projection image. Composite projection images are formed by replacing measured projection image data for pixels within the projection metal mask with calculated projection image data. A metal artifact reduced 3-D image is reconstructed from composite projections.

Abstract: A method for 3-D cephalometric analysis acquires reconstructed volume image data from a computed tomographic scan of a patient's head. The acquired volume image data simultaneously displays from at least a first 2-D view and a second 2-D view. For an anatomical feature of the head, an operator instruction positions a reference mark corresponding to the feature on either the first or the second displayed 2-D view and the reference mark displays on each of the at least first and second displayed 2-D views. In at least the first and second displayed 2-D views, one or more connecting lines display between two or more of the positioned reference marks. One or more cephalometric parameters are derived according to the positioned reference marks, the derived parameters are displayed.

Abstract: A method and apparatus for non-invasive measure of venous oxygen saturation, which can be useful for early diagnosis of microcirculatory dysfunction and treatment of medical conditions, such as septic shock, is disclosed. The method applies external stimulus to a patient to improve the signals to an oximeter yielding more reliable measurements. The device implementing the method uses superficial low frequency and low pressure pulse to the patient near the site of the oximeter as well as optionally controlling the patient's temperature near the site of the oximeter. The results also include non-invasive measurements of SpaO2, SpvO2 and O2E.

Abstract: A method for 3-D cephalometric analysis acquires reconstructed volume image data from a computed tomographic scan of a patient's head. The acquired volume image data simultaneously displays from at least a first 2-D view and a second 2-D view. For an anatomical feature of the head, an operator instruction positions a reference mark corresponding to the feature on either the first or the second displayed 2-D view and the reference mark displays on each of the at least first and second displayed 2-D views. In at least the first and second displayed 2-D views, one or more connecting lines display between two or more of the positioned reference marks. One or more cephalometric parameters are derived according to the positioned reference marks, the derived parameters are displayed.

Abstract: A method of generating a synthesized digital projection image, executed at least in part by a computer, acquires x-ray projection images at corresponding acquisition angles, and reconstructs a first volume image. Forward projection generates a preceding forward projection image at a first acquisition angle; a following forward projection image at an adjacent second acquisition angle; and an intermediate forward projection image for an intermediate angle. A synthesized projection image is formed by identifying a candidate patch of pixels from the intermediate forward projection image, matching a first patch of pixels from the preceding forward projection image and identifying a corresponding first acquired patch of pixels from the first acquired x-ray projection image, matching a second patch of pixels from the following forward projection image and matching a second acquired patch of pixels from the forward projection image. The first and second acquired patches are combined.

Abstract: A method for tomosynthesis volume reconstruction acquires at least a prior projection image of the subject at a first angle and a subsequent projection image of the subject at a second angle. A synthetic image corresponding to an intermediate angle between the first and second angle is generated by a repeated process of relating an area of the synthetic image to a prior patch on the prior projection image and to a subsequent patch on the subsequent projection image according to a bidirectional spatial similarity metric, wherein the prior patch and subsequent patch have n×m pixels; and combining image data from the prior patch and the subsequent patch to form a portion of the synthetic image. The generated synthetic image is displayed, stored, processed, or transmitted.

Abstract: A method for 3-D cephalometric analysis of a patient, executed at least in part on a computer processor, displays reconstructed volume image data from a computed tomographic scan of a patient's head from at least a first 2-D view and accepts an operator instruction that positions and displays at least one reference mark on the at least the first displayed 2-D view. One or more dentition elements within the mouth of the patient are segmented and one or more cephalometric parameters computed for the patient according to the at least one reference mark and the one or more segmented dentition elements. One or more results generated from analysis of the one or more computed cephalometric parameters are displayed.

Abstract: An apparatus captures radiographic images of an animal standing proximate the apparatus. A moveable x-ray source and a digital radiographic detector are hidden from view of the animal and are revolved about a portion of the animal's body to capture one or a sequence of radiographic images of the animal's body.

Abstract: A method of automatic tooth segmentation, the method executed at least in part on a computer system acquires volume image data for either or both upper and lower jaw regions of a patient and identifies image content for a specified jaw from the acquired volume image data. For the specified jaw, the method estimates average tooth height for teeth within the specified jaw, finds a jaw arch region, detects one or more separation curves between teeth in the jaw arch region, defines an individual tooth sub volume according to the estimated average tooth height and the detected separation curves, segments at least one tooth from within the defined sub-volume, and displays the at least one segmented tooth.

Abstract: A method for generating a 3-dimensional reconstruction model of an object of interest that lies within a volume, the method executed at least in part by a computer, acquires a first set of projection images of the volume at a first exposure and a first field of view and a second set of projection images of the object of interest within the volume at a second exposure that is higher than the first exposure and a second field of view that is narrower than the first field of view. An object of interest is reconstructed from the second set of projection images according to information related to portions of the volume that lie outside the object of interest. The reconstructed object of interest is displayed.

Abstract: A method for generating a 3-dimensional reconstruction model of an object of interest that lies within a volume, the method executed at least in part by a computer, acquires a first set of projection images of the volume at a first exposure and a first field of view and a second set of projection images of the object of interest within the volume at a second exposure that is higher than the first exposure and a second field of view that is narrower than the first field of view. An object of interest is reconstructed from the second set of projection images according to information related to portions of the volume that lie outside the object of interest. The reconstructed object of interest is displayed.

Abstract: A method for reducing metal artifacts in a volume radiographic image reconstructs a first 3-D-image using measured projection images and forms a 3-D image metal mask that contains metal voxels. For each measured projection image, a projection metal mask is a projection of the 3-D image metal mask. A 3-D prior image contains voxels within the 3-D image metal mask. Voxel values of the first 3-D image outside the 3-D image metal mask are replaced with a value representative of air or soft tissue. Non-metal voxels of the 3-D prior image are modified according to a difference between a pixel value related to the nonmetal voxel and the corresponding pixel value in a calculated projection image. Composite projection images are formed by replacing measured projection image data for pixels within the projection metal mask with calculated projection image data. A metal artifact reduced 3-D image is reconstructed from composite projections.

Abstract: A method for reporting bone mineral density values for a patient, the method executed at least in part by a computer includes accessing a 3-D volume image that includes at least bone content and background. A 3-D bone region is automatically segmented from the background to generate a 3-D bone volume image having a plurality of voxels. One or more bone mineral density values are computed from voxel values of the 3-D bone volume image. A 3-D mapping of the one or more computed bone mineral density values is generated and displayed, stored, or transmitted.

Abstract: A method of automatic tooth segmentation, the method executed at least in part on a computer system acquires volume image data for either or both upper and lower jaw regions of a patient and identifies image content for a specified jaw from the acquired volume image data. For the specified jaw, the method estimates average tooth height for teeth within the specified jaw, finds a jaw arch region, detects one or more separation curves between teeth in the jaw arch region, defines an individual tooth sub volume according to the estimated average tooth height and the detected separation curves, segments at least one tooth from within the defined sub-volume, and displays the at least one segmented tooth.

Abstract: A method of automatic tooth segmentation, the method executed at least in part on a computer system acquires volume image data for either or both upper and lower jaw regions of a patient and identifies image content for a specified jaw from the acquired volume image data. For the specified jaw, the method estimates average tooth height for teeth within the specified jaw, finds a jaw arch region, detects one or more separation curves between teeth in the jaw arch region, defines an individual tooth sub volume according to the estimated average tooth height and the detected separation curves, segments at least one tooth from within the defined sub-volume, and displays the at least one segmented tooth.

Abstract: Method and/or apparatus embodiments can process volume image data of a subject. An exemplary method includes obtaining a first group of two-dimensional radiographic images of the subject, wherein each of the images is obtained with a detector and a radiation source at a different scan angle. The method arranges image data from the first group of images in an image stack so that corresponding pixel data from the detector is in register for each of the images in the image stack. Pixels that represent metal objects are segmented from the image stack and data replaced for at least some of the segmented pixels to generate a second group of modified two-dimensional radiographic images. The second group of images is combined with the first group to generate a three-dimensional volume image according to the combined images and an image slice from the three-dimensional volume image is displayed.

Abstract: A method for registering a first imaging detector to a surface projects a sequence of k images toward the surface, wherein k?4, wherein each of the k images has a pattern of lines that extend in a direction that is orthogonal to a movement direction. The pattern encodes an ordered sequence of labels, each label having k binary elements, such that, in the movement direction, any portion of the pattern that is k equal increments long encodes one label of the ordered sequence. The method obtains, for at least a first pixel in the first imaging detector, along at least one line that is parallel to the movement direction, a first sequence of k signal values indicative of the k binary elements of a first label from the ordered sequence of labels and correlates the at least the first pixel in the first imaging detector to the surface.

Abstract: A method for segmenting a feature of interest from a volume image acquires image data elements from the image of a subject. One or more boundary points along a boundary of the feature of interest are identified according to one or more geometric primitives with reference to the displayed view. A foreground seed curve is defined according to the one or more identified boundary points. A background field array that lies outside of, and is spaced from, the foreground seed curve by a predetermined distance, is defined. Segmentation is applied to the volume image according to foreground values obtained according to image data elements that are spatially bounded on or within the foreground seed curve and according to background field array values to create a segmented feature of interest.

Abstract: A method for 3-D interactive examination of a subject tooth, executed at least in part by a computer, obtains volume image data containing at least the subject tooth and background content adjacent to the subject tooth and displays a first image from the volume data that shows at least the subject tooth and the background content. A portion of the background content in the first image is identified according to a first operator instruction. Tooth content for at least the subject tooth in the first image is identified according to a second operator instruction. At least the subject tooth is segmented from within the volume data according to the first and second operator instructions. The segmented subject tooth is then displayed.