Abstract: Methods and systems are described for removing reflective artifacts from an imaging model. An x-ray detector captures x-ray images that include a structure and an imaging device captures a surface scan of the same structure. An image processor constructs a three-dimensional CT model of the structure from the x-ray images and constructs a three-dimensional surface model of the structure from the surface scan. The image processor is configured to resize and orient the surface model and/or the CT model so that they are the same scale and orientation, overlay the surface model onto the CT model, and detect data points in the combined data set that extend beyond a surface of the structure in the surface model. The detected data points represent artifacts in the CT model and are adjusted by interpolation to produce an artifact-reduced CT model.

Abstract: Methods and systems are described for removing reflective artifacts from an imaging model. An x-ray detector captures x-ray images that include a structure and an imaging device captures a surface scan of the same structure. An image processor constructs a three-dimensional CT model of the structure from the x-ray images and constructs a three-dimensional surface model of the structure from the surface scan. The image processor is configured to resize and orient the surface model and/or the CT model so that they are the same scale and orientation, overlay the surface model onto the CT model, and detect data points in the combined data set that extend beyond a surface of the structure in the surface model. The detected data points represent artifacts in the CT model and are adjusted by interpolation to produce an artifact-reduced CT model.

Abstract: Methods and systems are described for removing reflective artifacts from an imaging. A first volumetric model and a second volumetric model of the same object are accessed from a computer-readable memory. The orientation and scale of at least one of the two models is repeatedly and automatically adjusted until an optimized orientation and scale is determined that correlates the first volumetric model and the second volumetric model. The second volumetric model is then overlaid onto the first volumetric model. Any data points in the first volumetric model that extend beyond a surface of the second volumetric model are detected and removed to create an artifact-reduced volumetric model.

Abstract: A method and a system for correcting and reconstruing a plurality of projection images based on detected patient motion. The method includes obtaining a plurality of projection images generated by a scanner. Each of the plurality of projection images includes at least three markers. Each of the at least three markers has a measured three-dimensional position and measured positions on a detector panel of the scanner in a first dimension and a second dimension. The method further includes determining a position error vector for each of the plurality of projection images based on the at least three markers in each of the plurality of projection images, the position error vector defining patient motion in the projection image.

Abstract: Methods and systems are described for removing reflective artifacts from an imaging. A first volumetric model and a second volumetric model of the same object are accessed from a computer-readable memory. The orientation and scale of at least one of the two models is repeatedly and automatically adjusted until an optimized orientation and scale is determined that correlates the first volumetric model and the second volumetric model. The second volumetric model is then overlaid onto the first volumetric model. Any data points in the first volumetric model that extend beyond a surface of the second volumetric model are detected and removed to create an artifact-reduced volumetric model.

Abstract: A method and a system for correcting and reconstruing a plurality of projection images based on detected patient motion. The method includes obtaining a plurality of projection images generated by a scanner. Each of the plurality of projection images includes at least three markers. Each of the at least three markers has a measured three-dimensional position and measured positions on a detector panel of the scanner in a first dimension and a second dimension. The method further includes determining a position error vector for each of the plurality of projection images based on the at least three markers in each of the plurality of projection images, the position error vector defining patient motion in the projection image.

Abstract: Methods and systems are described for removing reflective artifacts from an imaging model of a patient's teeth. A first volumetric model and a second volumetric model of the patient's teeth are accessed from a computer-readable memory. The orientation and scale of at least one of the two models is repeatedly and automatically adjusted until an optimized orientation and scale is determined that correlates the first volumetric model and the second volumetric model. The second volumetric model is then overlaid onto the first volumetric model. Any data points in the first volumetric model that extend beyond a surface of the patient's teeth in the second volumetric model are detected and removed to create an artifact-reduced volumetric model.

Abstract: Devices for presentation of digital radiographic images. One device includes a memory for storing at least one radiographic image and a computer connected to the memory. The computer includes a processor and a user interface module. The user interface module is configured to generate a graphical user interface and to cause the at least one radiographic image to be displayed on a display in a first mode and in a light box mode that simulates the appearance of a physical light box.

Abstract: Methods and systems are described for removing reflective artifacts from an imaging model of a patient's teeth. A first volumetric model and a second volumetric model of the patient's teeth are accessed from a computer-readable memory. The orientation and scale of at least one of the two models is repeatedly and automatically adjusted until an optimized orientation and scale is determined that correlates the first volumetric model and the second volumetric model. The second volumetric model is then overlaid onto the first volumetric model. Any data points in the first volumetric model that extend beyond a surface of the patient's teeth in the second volumetric model are detected and removed to create an artifact-reduced volumetric model.

Abstract: A method and a system for determining patient motion in an image. The method includes obtaining an image based on image data generated by a scanner during a scan. The image includes at least three markers assumed to be in a rigid or semi-rigid configuration. Each of the at least three markers has actual measured positions on a detector panel of the scanner in a first dimension and a second dimension. The method further includes determining a reference three-dimensional position for each of the at least three markers and defining equations describing the relationship between the reference three-dimensional position and the actual measured positions of each of the at least three markers, geometric parameters of the scanner, and patient motion.

Abstract: A method and system of rapidly detecting and mapping a plurality of marker points identified in a sequence of projection images to a physical marker placed on a patient or other scanned object. Embodiments of the invention allow a marker physical mapping module executable by an electronic processing unit to obtain a sequence of images based on image data generated by a scanner. Each image in the sequence of images represents an angle of rotation by the scanner and includes a plurality of marker points each having a U position and a V position. Expected U and V positions for the physical marker are calculated and a list of candidate marker points is created based on the expected positions. The images are processed and selected candidate marker points are added to a good point list.

Abstract: A method and system of determining a sub-pixel point position of a marker point in an image. Embodiments of the invention allow a marker point sub-pixel localization module executable by an electronic processing unit to obtain an image, including a marker point, and to derive both a background corrected marker point profile and a background and baseline corrected marker point profile. Additionally, embodiments of the invention allow defining of a sub-pixel position of the marker point as a center of a peak of the background corrected marker point profile. Thus, embodiments of the invention allow for rapidly detecting and localizing external markers placed on a patient in projection images.

Abstract: A system for removing artifacts caused by x-ray reflective materials from an x-ray image of a patient's teeth. The system includes an x-ray source, an x-ray detector that captures several x-ray images, and a surface scanner that captures a surface scan of the patient's teeth. An image processor generates three-dimensional models from the optical surface data and the CT volumetric data. The models are resized and oriented to be of the same scale and orientation and then overlaid to create a combined data set. Data points that extend beyond the surface of the patient's teeth in the surface model are identified and may be removed if it is determined that they are artifacts. An artifact-reduced CT model is then displayed.

Abstract: Systems and methods for generating an image. One system includes a processor. The processor is configured to receive a requested object field-of-view and determine if the object field-of-view is possible based on constraints of an imaging system, wherein the constraints include dimensions of a detector panel and motion limits of a collimator assembly. If the object field-of-view is possible, the processor is configured to dynamically generate a set of collimator motor commands and reconstruction parameters based on the object field-of-view, calibration parameters of the collimator assembly, and geometric calibration parameters of the imaging system. The processor is also configured to provide the set of collimator motor commands to the collimator assembly to position shutters of the collimator assembly to illuminate the object field-of-view.

Abstract: A mechanism for rapidly detecting and localizing external markers placed on a patient in projection images. Markers can be detected even in the presence of dense surrounding anatomy and extensive patient motion. Once the positions of the marker points on the projection images are extracted, the marker points can be used to perform marker-based patient motion detection. In addition to motion correction, the rapid detection and localization may also be used for scanner calibration, automatic cephalometric measurements, and quality control assessment.

Abstract: A mechanism for rapidly detecting and localizing external markers placed on a patient in projection images. Embodiments of the invention allow the markers to be detected even in the presence of dense surrounding anatomy and extensive patient motion. Once the positions of the marker points on the projection images are extracted, the marker points can be used to perform marker-based patient motion detection. Embodiments of the invention can also be used outside of motion correction, such as for scanner calibration, automatic cephalometric measurements, and quality control assessment.

Abstract: A method and system of determining a radial distance (R), an angular position (?), and an axial position (Z) of a marker identified in a sequence of projection images. A marker three-dimensional localization module (executable by the electronic processing unit) obtains a sequence of images based on image data generated by a scanner. Each image in the sequence of images represents an angle of rotation by the scanner and includes a marker point position. The behavior of first values and second values of the marker point positions are analyzed through the sequence of images to determine the radial distance of the marker, the angular position of the marker, and the axial position of the marker allowing for rapidly detecting and localizing external markers placed on a patient in projection images.

Abstract: A system for removing artifacts caused by x-ray reflective materials from an x-ray image of a patient's teeth. The system includes an x-ray source, an x-ray detector that captures several x-ray images, and a surface scanner that captures a surface scan of the patient's teeth. An image processor generates three-dimensional models from the optical surface data and the CT volumetric data. The models are resized and oriented to be of the same scale and orientation and then overlaid to create a combined data set. Data points that extend beyond the surface of the patient's teeth in the surface model are identified and may be removed if it is determined that they are artifacts. An artifact-reduced CT model is then displayed.

Abstract: A method and a system for correcting and reconstruing a plurality of projection images based on detected patient motion. The method includes obtaining a plurality of projection images generated by a scanner. Each of the plurality of projection images includes at least three markers. Each of the at least three markers has a measured three-dimensional position and measured positions on a detector panel of the scanner in a first dimension and a second dimension. The method further includes determining a position error vector for each of the plurality of projection images based on the at least three markers in each of the plurality of projection images, the position error vector defining patient motion in the projection image.

Abstract: A method and system of determining a sub-pixel point position of a marker point in an image. Embodiments of the invention allow a marker point sub-pixel localization module executable by an electronic processing unit to obtain an image, including a marker point, and to derive both a background corrected marker point profile and a background and baseline corrected marker point profile. Additionally, embodiments of the invention allow defining of a sub-pixel position of the marker point as a center of a peak of the background corrected marker point profile. Thus, embodiments of the invention allow for rapidly detecting and localizing external markers placed on a patient in projection images.