Abstract: A method, apparatus and computer program product are provided for constructing a diagnostic network model in a more efficient and timely manner and with improved consistency. A structured electronic representation of a document is automatically reviewed to identify the symptoms experienced by the complex system, the plurality of components of the complex system and the causal relationships between a failure of the respective components and the occurrence of the various symptoms. Respective probabilities can be associated with the causal relationships between the symptoms and the failure of the various components. A network model, such as a Bayesian network model, may then be automatically constructed to represent the symptoms, the components, the causal relationships between failure of the components and exhibition of the symptoms, and the probabilities of the respective causal relationships.

Abstract: A method for processing a fluoroscopic image includes generating a lag prediction model, scanning an object at a first radiation dosage with an imaging system including at least one radiation source and at least one detector array, and periodically updating the lag prediction model during the scan to generate at least one fluoroscopic image of the object.

Abstract: An apparatus for use with a detector system including a solid state flat panel detector and an image processor, the detector including a plurality of pixels, each pixel generating an initial intensity signal, the initial signals together defining an initial image, the processor storing an initial bad pixel map that includes a known bad pixel set, after signals are generated, the processor automatically using intensity signals corresponding to other than the bad pixel set to generate replacement intensity signals for each of the bad pixel set pixels thereby generating a corrected image, the apparatus for identifying additional bad pixels, the apparatus comprising a processor that, after the image data is collected, examines at least one of the initial image and the corrected image to identify a likely additional bad pixel set including pixels that have unexpected values and an interface for indicating the likely bad set to a system user.

Abstract: A detector imaging system having an apparatus and method for correcting defective pixels in a current acquired image is disclosed herein. The system performs the correction of defective pixels using image feature information and temporal information. The system includes a correction scheme which includes determining a temporal matrix based on the current acquired image, at least one prior acquired image, and a filter weight; determining a local gradient based in part on the temporal matrix and a gradient kernel; and providing a correction value based on the local gradient to correct the defective pixel. The correction scheme is repeated a plurality of times as desired to correct all the defective pixels in the current acquired image.

Abstract: A method and system for controlling a dynamic range of a medical diagnostic image provided by a medical diagnostic system. A target dynamic range is identified independent of a dynamic range of an original medical image. A presentation map is generated defining a relation between the dynamic range of the original medical image representative of a patient and the target dynamic range. A gray level-optical density model may define the relation between gray levels of the original medical image and target optical densities of the presentation map, the gray level-optical density model being calculated based on film characteristics, selected optical densities for anatomical structure or on a measured dynamic range. A presentation image is created having the target dynamic range based on a the presentation map and original medical image.

Abstract: In one aspect of the invention a method for processing a fluoroscopic image is provided. The method includes scanning an object with an imaging system including at least one radiation source and at least one detector array, acquiring a plurality of dark images to generate a baseline image, acquiring a plurality of lag images subsequent to the baseline image, determining a plurality of parameters of a power law using at least one lag image and at least one baseline image, and performing a log—log extrapolation of the power law including the determined parameters.

Abstract: A technique for selectively processing data from a digital detector includes determining an asymmetrical image area produced by orientation of a radiation source assembly. The assembly may include a radiation source and a collimator, which may be separately orientable. The image area is computed based upon the orientation of the radiation source assembly that projects a radiation beam towards an imaging plane. Image data from a detector within the imaging plane is selectively processed to improve computational efficiency. The system may also determine whether the image area falls within the imaging surface of the detector and inform an operator or inhibit an exposure if such is not the case.

Abstract: In one aspect of the invention a method for processing a fluoroscopic image is provided. The method includes scanning an object with an imaging system including at least one radiation source and at least one detector array, acquiring a plurality of dark images to generate a baseline image, acquiring a plurality of lag images subsequent to the baseline image, determining a plurality of parameters of a power law using at least one lag image and at least one baseline image, and performing a log-log extrapolation of the power law including the determined parameters.

Abstract: In recent years, x-ray imaging, which has been used to diagnose millions of illnesses and injuries, has evolved to use digital imaging instead of photographic film as a recording medium. Digital x-ray systems typically include an x-ray source, an x-ray focusing grid, and an array of light or x-ray detectors. Because of detector imperfections and other system factors, such as x-ray field non-uniformity and grid artifacts, digital x-ray images are often corrected, or compensated, before use. To this end, many digital x-ray systems include numerous application-specific correction maps, which unfortunately require regular maintenance that is not only time-consuming but expensive in terms of system downtime. Accordingly, the inventors devised new methods and systems for correcting application images that require maintenance of fewer correction maps. One exemplary implementation determines grid-only and non-grid correction maps and corrects application images based on a combination of these correction maps.

Abstract: An automatic exposure control for an x-ray system using a large area solid state x-ray detector (26) includes an exposure control (36, 34) arranged to generate data of interest within the data generated by the detector and to adjust the dosage of x-rays to a predetermined level in response to data of interest so that an x-ray image of a patient is generated using the predetermined level.

Abstract: A technique for selectively processing data from a digital detector includes determining an asymmetrical image area produced by orientation of a radiation source assembly. The assembly may include a radiation source and a collimator, which may be separately orientable. The image area is computed based upon the orientation of the radiation source assembly that projects a radiation beam towards an imaging plane. Image data from a detector within the imaging plane is selectively processed to improve computational efficiency. The system may also determine whether the image area falls within the imaging surface of the detector and inform an operator or inhibit an exposure if such is not the case.

Abstract: In an X-ray imaging system, an arrangement is provided for readily aligning the system detector with the X-ray beam field, i.e., the projection of the X-ray beam into the plane of the detector. The arrangement is adapted for correcting or compensating for distortion which results from X-ray beam angulation, wherein the beam is projected toward the detector plane at an angle of less than 90°. Initially, the system X-ray tube is positioned to project the X-ray beam at a given beam direction angle &phgr;. A beam width angle &ggr;1 is then computed, from the given angle &phgr; and from specified values of the source-to-image distance and the length of the projected beam field. Thereupon, an offset value is determined from &ggr;1, &phgr; and the source-to-image distance to locate the geometric center of the beam field, and the center of the detector is aligned therewith.

Abstract: An automatic exposure control for an x-ray system using a large area solid state x-ray detector (26) includes an exposure control (36, 34) arranged to generate data of interest within the data generated by the detector and to adjust the dosage of x-rays to a predetermined level in response to data of interest so that an x-ray image of a patient is generated using the predetermined level.

Abstract: In an X-ray imaging system comprising an X-ray source, a digital X-ray detector and a display device, an arrangement is provided for setting or establishing the dynamic range of the image at the display device. The detector is operated to provide a set of count values representing X-ray image data acquired by the detector from an object of imaging, and a set of standardized values, such as optical density values, is derived from the count values. The optical density values collectively define a range of optical density values, and the dynamic range of the display device is mapped thereto. The display device is enabled to present an image of the object which appears similar to or substantially the same as an image of the object presented by, for example, a specified analog X-ray film.

Abstract: In an X-ray imaging system comprising an X-ray source, a digital X-ray detector and a display device, an arrangement is provided for setting or establishing the dynamic range of the image at the display device. The detector is operated to provide a set of count values representing X-ray image data acquired by the detector from an object of imaging, and a set of standardized values, such as optical density values, is derived from the count values. The optical density values collectively define a range of optical density values, and the dynamic range of the display device is mapped thereto. The display device is enabled to present an image of the object which appears similar to or substantially the same as an image of the object presented by, for example, a specified analog X-ray film.

Abstract: Disclosed herein is a radiographic imaging system which performs system performance monitoring by (1) using automatic exposure control (AEC) components to predict the average image gray level; (2) obtaining measured average image gray levels from the portions of the X-ray detector situated in the X-ray shadow of the AEC components; and then (3) comparing the predicted and measured values. The predicted values are determined by use of a prediction model which is modified by a learning system over successive exposures to provide more accurate predictions. After the learning system has sufficiently developed the prediction model, the error between the predicted and measured gray level values may be monitored in later exposures and an error routine can be activated if the error exceeds a predetermined threshold. In this case, the error may indicate that system components in the imaging chain (e.g., the detector or AEC components) require maintenance.