Abstract: A medical imaging system (200) includes a masking unit (234), an image registration unit (238), a motion estimator (240) and a motion compensating reconstructor (244). The masking unit constructs a mask for each reconstructed volumetric phase image of a plurality of reconstructed volumetric phase images that masks portions of a corresponding image external to an anatomical model fitted to a segmented at least one anatomical structure, 5 wherein the plurality of reconstructed volumetric phase images include a target phase and a plurality of temporal neighboring phases reconstructed from projection data. The image registration unit registers the masked reconstructed volumetric phase images. The motion estimator estimates motion between the target phase and the plurality of temporal neighboring phases according to the model based on the registered masked reconstructed 10 volumetric phase images.

Abstract: The invention relates to a photon counting x-ray radiation detection system. The system (31) comprises an x-ray radiation device (2) for providing polychromatic x-ray radiation (4) for traversing an examination zone (5) during a detection period of a scan. A photon counting detection device (6) comprising detection elements (3) detects the x-ray radiation after having traversed the examination zone and measures for each detection element photon counts in one or more energy bins during the detection period. A correction unit (12) estimates for each detection element an amount of a build up charge present in the detection element and corrects the measured photon counts for the detection element based on the estimated amount of the build up charge. This allows the corruption of the photon count rates caused by the build up charges to be compensated and to improve the determination of the photon counts.

Abstract: The invention relates to a photon counting x-ray radiation detection system. The system (31) comprises an x-ray radiation device (2) for providing polychromatic x-ray radiation (4) for traversing an examination zone (5) during a detection period of a scan. A photon counting detection device (6) comprising detection elements (3) detects the x-ray radiation after having traversed the examination zone and measures for each detection element photon counts in one or more energy bins during the detection period. A correction unit (12) estimates for each detection element an amount of a build up charge present in the detection element and corrects the measured photon counts for the detection element based on the estimated amount of the build up charge. This allows the corruption of the photon count rates caused by the build up charges to be compensated and to improve the determination of the photon counts.

Abstract: The invention relates to a detection apparatus for detecting radiation. The detection apparatus comprises a GOS material (20) for generating scintillation light depending on the detected radiation (25), an optical filter (24) for reducing the intensity of a part of the scintillation light having a wavelength being larger than 650 nm, and a detection unit (21) for detecting the filtered scintillation light. Because of the filtering procedure relatively slow components, i.e. components corresponding to a relatively large decay time, of the scintillation light weakly constribute to the detection process or are not detected at all by the detection unit, thereby increasing the temporal resolution of the detection apparatus. The resulting fast detection apparatus can be suitable for kVp-switching computed tomography systems.

Abstract: A method includes analyzing a spectral projection image of a portion of a subject, generating a value quantifying an amount of a target specific contrast material in a region of interest of the spectral projection image, and generating a signal indicative of a presence of the target in response to the value satisfying a predetermined threshold level.

Abstract: The present invention discloses a method to calibrate a photon counting detector (3). An absorption filter (7) is moved transversely through a photon beam (8) emitted towards the detector (3) to average out the effect of inhomogeneties of the absorption filter (7). The invention also relates to an absorption filter assembly and an imaging device (1) comprising such an absorption filter assembly.

Abstract: An imaging system includes a radiation source (108) configured to rotate about an examination region (106)and emit radiation that traverses the examination region. The imaging system further includes an array of radiation sensitive pixels (112) configured to detect radiation traversing the examination region and output a signal indicative of the detected radiation. The array of radiation sensitive pixels is disposed opposite the radiation source, across the examination region. The imaging system further includes a rigid flux filter device (130) disposed in the examination region between the radiation source and the radiation sensitive detector array of photon counting pixels. The rigid flux filter device is configured to filter the radiation traversing the examination region and incident thereon. The radiation leaving the rigid flux filter device has a predetermined flux.

Abstract: A method includes determining calibration factors for calibrating photon-counting detectors of a spectral imaging system by combining a heuristic calibration of the photon-counting detectors and an analytical calibration of the photon-counting detectors and generating a set of photon-counting calibration factors based on the combining of the a heuristic calibration and the analytical calibration. The photon-counting calibration factors, when applied to measured energy-resolved data from the photon-counting detectors of a spectral CT scan of a subject or object, mitigate spectral distortion caused by a radiation intensity profile shaper that filters a radiation beam of the spectral CT scan.

Abstract: The present invention discloses a method to calibrate a photon counting detector (3). An absorption filter (7) is moved transversely through a photon beam (8) emitted towards the detector (3) to average out the effect of inhomogeneties of the absorption filter (7). The invention also relates to an absorption filter assembly and an imaging device (1) comprising such an absorption filter assembly.

Abstract: The invention relates to an image generation apparatus (1) for generating an image of an object. A reconstruction unit (10) reconstructs the image based on provided measured projection values such that costs defined by a cost function are reduced, wherein the cost function depends on differences between calculated projection values, which have been determined by simulating a forward projection through the image, and the provided measured projection values, and wherein a degree of dependence of the cost function on a respective difference depends on the respective difference. This can allow for a consideration of a degree of disturbance of the measured projection values by motion and/or by an incomplete illumination of the object during the reconstruction process, which can lead to a reconstruction of an image having an improved image quality.

Abstract: Detection apparatus for detecting radiation The invention relates to a detection apparatus for detecting radiation. The detection apparatus comprises at least two scintillators (14, 15) having different temporal behaviors, each generating scintillation light upon reception of radiation, wherein the generated scintillation light is commonly detected by a scintillation light detection unit (16), thereby generating a common light detection signal. A detection values determining unit determines first detection values by applying a first determination process and second detection values by applying a second determination process, which is different to the first determination process, on the detection signal. The first determination process includes frequency filtering the detection signal.

Abstract: A method includes determining calibration factors for calibrating photon-counting detectors of a spectral imaging system by combining a heuristic calibration of the photon-counting detectors and an analytical calibration of the photon-counting detectors and generating a set of photon-counting calibration factors based on the combining of the a heuristic calibration and the analytical calibration. The photon-counting calibration factors, when applied to measured energy-resolved data from the photon-counting detectors of a spectral CT scan of a subject or object, mitigate spectral distortion caused by a radiation intensity profile shaper that filters a radiation beam of the spectral CT scan.

Abstract: The invention relates to an imaging apparatus (31) for imaging an object. A reconstruction unit (12) determines component projection data values, which correspond to, for example, a base material of the object, and reconstructs an image of the object based on the determined component projection data values. A component projection data value, which corresponds to a ray, is determined as a combination of weighted base functions, which depend on energy projection data values of the same ray and the orientation of the same ray. This allows considering a possible dependency of the corresponding decomposition on the orientation of the ray, thereby allowing the imaging apparatus to improve the quality of decomposing the provided energy projection data values into the component projection data values and thus of a finally reconstructed image of the object, which is reconstructed based on the component projection data values.

Abstract: The invention relates to an imaging system (30) for imaging an object. A projection data providing unit (31) provides acquired spectral projection data of an object comprising at least two components, and a reconstruction unit (10) iteratively reconstructs at least two final component images of the object by performing several iteration steps, in which at least two intermediate component images are updated based on the acquired spectral projection data and a penalty term, which is indicative of the correlated noise between the at least two intermediate component images. Since the at least two intermediate component images are updated based on the acquired spectral projection data and a penalty term, which is indicative of the correlated noise, correlated noise is penalized during the iterative reconstruction. The finally resulting component images of the object are therefore less corrupted by correlated noise and have an improved image quality.

Abstract: The invention relates to an imaging apparatus for imaging an object of interest. An analytical reconstruction unit (12) analytically reconstructs an analytical image of the object from detection data, in particular, from projection data, and an iterative reconstruction unit (13) iteratively reconstructs an iterative image of the object from the detection data, wherein a combination unit (14) combines the analytical image and the iterative image for generating a combination image. An iterative image can comprises shading artifacts, which may be caused by preprocessing the detection data before performing the iterative reconstruction. An analytical image shows reduced shading artifacts, in particular, shows no shading artifacts at all. Thus, by combining the analytical image and the iterative image a combination image can be generated, in which the shading artifacts are reduced in comparison to an iterative image, thereby improving the quality of the reconstructed final image of the object of interest.

Abstract: An imaging system includes radiation source (106) that emits radiation that traverses an examination region and a portion of a subject therein and a detector array (114) that detects radiation that traverses the examination region and the portion of the subject therein and generates a signal indicative thereof. A volume scan parameter recommender (120) recommends at least one spectral scan parameter value for a volume scan of the portion of the subject based on a spectral decomposition of first and second 2D projections acquired by the radiation source and detector array. The first and second 2D projections have different spectral characteristics. A console (122) employs the recommended at least one spectral scan parameter value to perform the volume scan of the portion of the subject.

Abstract: The invention relates to a detection apparatus for detecting radiation. The detection apparatus comprises a GOS material (20) for generating scintillation light depending on the detected radiation (25), an optical filter (24) for reducing the intensity of a part of the scintillation light having a wavelength being larger than 650 nm, and a detection unit (21) for detecting the filtered scintillation light. Because of the filtering procedure relatively slow components, i.e. components corresponding to a relatively large decay time, of the scintillation light weakly constribute to the detection process or are not detected at all by the detection unit, thereby increasing the temporal resolution of the detection apparatus. The resulting fast detection apparatus can be suitable for kVp-switching computed tomography systems.

Abstract: Detection apparatus for detecting radiation The invention relates to a detection apparatus for detecting radiation. The detection apparatus comprises at least two scintillators (14, 15) having different temporal behaviors, each generating scintillation light upon reception of radiation, wherein the generated scintillation light is commonly detected by a scintillation light detection unit (16), thereby generating a common light detection signal. A detection values determining unit determines first detection values by applying a first determination process and second detection values by applying a second determination process, which is different to the first determination process, on the detection signal. The first determination process includes frequency filtering the detection signal.

Abstract: The invention relates to an imaging apparatus (31) for imaging an object. A reconstruction unit (12) determines component projection data values, which correspond to, for example, a base material of the object, and reconstructs an image of the object based on the determined component projection data values. A component projection data value, which corresponds to a ray, is determined as a combination of weighted base functions, which depend on energy projection data values of the same ray and the orientation of the same ray. This allows considering a possible dependency of the corresponding decomposition on the orientation of the ray, thereby allowing the imaging apparatus to improve the quality of decomposing the provided energy projection data values into the component projection data values and thus of a finally reconstructed image of the object, which is reconstructed based on the component projection data values.

Abstract: A medical imaging system includes a generally stationary gantry (102) and a rotating gantry (106), rotatably supported by the generally stationary gantry (102), that rotates about a longitudinal axis around an examination region. The medical imaging system further includes a radiation source (112) that emits a radiation beam that traverses the examination region. The radiation source (112) is moveably affixed to the rotating gantry (106) so as to translate in a direction of the longitudinal axis with respect to the rotating gantry (106) while scanning a subject in the examination region. The medical imaging system further includes a detector array (120) that detects the radiation beam that traverses the examination region and generates a signal indicative thereof. The detector array (120) is moveably affixed to the rotating gantry (106) so as to move in coordination with the radiation source (112) while scanning the subject in the examination region.