Abstract: A reconstruction system includes a decomposer (204) configured to decompose at least two sets of projection data generated via kVp switching between at least two radiation source voltages. Each set corresponds to a different one of the at least two radiation source voltages. The system further includes a spectral channel (206) configured to process the at least two sets of projection data and generate spectral image data. The system further includes a non-spectral channel (208) configured to process the at least two sets of projection data and generate non-spectral image data for a predetermined reference kVp.

Abstract: The present disclosure discloses methods and systems for obtaining a radiographic image. The method may include obtaining a control instruction for controlling an imaging device to image a subject; determining, based on information reflecting a user's behavior in using the imaging device, adjustment parameters of a radiation generating device in the imaging device; and based on the control instruction, determining target exposure parameters at least based on a parameter control curve or biological information of the subject, the parameter control curve including a preset first parameter control curve or a second parameter control curve determined based on operation data of the imaging device, and the biological information including at least a weight and an overall content of each component of the subject; and imaging, based on the target exposure parameters, the subject to obtain the radiographic image.

Abstract: In tomosynthesis imaging which uses a radiation source that generates radiation and an Al filter and a Cu filter that change the quality of the radiation, irradiates a breast with the radiation emitted from the radiation source at a plurality of irradiation positions having different irradiation angles, and switches the Al filter and the Cu filter at each of the irradiation positions such that the radiation having different qualities is emitted to capture a plurality of radiographic images of the breast at each of the irradiation positions, a CPU performs control to set a last filter used at an n-th irradiation position as an initial filter used at an (n+1)-th irradiation position.

Abstract: A method and system for determining a dose of modulation (DOM) profile are provided. The method may include obtaining a 3D image and a topogram image of the object. The method may further include obtaining a dose of modulation (DOM) profile generation model. The DOM profile generation model may be generated by training a preliminary model based on a plurality of sample CT images, a plurality of sample 3D images corresponding to the plurality of sample CT images, respectively, and a plurality of sample topogram images corresponding to the plurality of sample CT images, respectively. The method may further include executing the DOM profile generation model to generate a DOM profile related to a computed tomography (CT) scan of the object based on the 3D image and the topogram image of the object.

Abstract: Devices, methods, and program storage devices for training and leveraging machine learning (ML) models to use in image registration, especially on unaligned multispectral images, are disclosed, comprising: obtaining aligned multispectral image data; generating a first plurality of feature descriptors for features identified in the aligned multispectral image data; generating a training set of feature descriptor pairs based on the first plurality of feature descriptors; and training a ML model based on the training set of feature descriptor pairs, wherein the trained ML model is configured to determine matches between features in unaligned multispectral image data.

Abstract: A method may include obtaining first image data relating to a region of interest (ROI) of a first subject. The first image data corresponding to a first equivalent dose level may be acquired by a first device. The method may also include obtaining a model for denoising relating to the first image data and determining second image data corresponding to an equivalent dose level higher than the first equivalent dose level based on the first image data and the model for denoising. In some embodiments, the method may further include determining information relating to the ROI of the first subject based on the second image data and ecording the information relating to the ROI of the first subject.

Abstract: A method is for capturing projection data. The method includes positioning the first diaphragm jaw and a second diaphragm jaw to set a layer collimation of a fan beam of radiation via the first diaphragm jaw and the second diaphragm jaw; capturing projection data of a region of a patient to be imaged via a detector and radiation source rotated in a plane of rotation, moving the region of the patient to be imaged relative to the plane of rotation, the fan beam penetrating the region of the patient to be imaged and striking the detector; and moving at least one of the first and second diaphragm jaw during the capturing, to dynamically adjust a position of a boundary surface of the fan beam to a position of a boundary surface of the region, to avoid the fan beam penetrating the patient outside the region to be imaged.

Abstract: A method may include obtaining first image data relating to a region of interest (ROI) of a first subject. The first image data corresponding to a first equivalent dose level may be acquired by a first device. The method may also include obtaining a model for denoising relating to the first image data and determining second image data corresponding to an equivalent dose level higher than the first equivalent dose level based on the first image data and the model for denoising. In some embodiments, the method may further include determining information relating to the ROI of the first subject based on the second image data and recording the information relating to the ROI of the first subject.

Abstract: A method may include obtaining first image data relating to a region of interest (ROI) of a first subject. The first image data corresponding to a first equivalent dose level may be acquired by a first device. The method may also include obtaining a model for denoising relating to the first image data and determining second image data corresponding to an equivalent dose level higher than the first equivalent dose level based on the first image data and the model for denoising. In some embodiments, the method may further include determining information relating to the ROI of the first subject based on the second image data and recording the information relating to the ROI of the first subject.

Abstract: Methods and systems are provided for determining scan settings for a localizer scan based on a magnetic resonance (MR) calibration image. In one example, a method for magnetic resonance imaging (MRI) includes acquiring an MR calibration image of an imaging subject, mapping, by a trained deep neural network, the MR calibration image to a corresponding anatomical region of interest (ROI) attribute map for an anatomical ROI of the imaging subject, adjusting one or more localizer scan parameters based on the anatomical ROI attribute map, and acquiring one or more localizer images of the anatomical ROI according to the one or more localizer scan parameters.

Abstract: According to one embodiment, an X-ray computed tomography apparatus includes an X-ray tube, a detector, and processing circuitry. The X-ray tube emits X-rays. The detector detects X-rays that have been emitted from the X-ray tube and have passed through the subject. The processing circuitry sets an imaging condition. The processing circuitry evaluates the imaging condition based on information on a lower limit range of a count value of the detected X-rays that may cause image degradation.

Abstract: In a CT scanning method of bolus tracking, multiple CT scans are performed on a region of interest (ROI) of a subject while a contrast agent is injected into the subject. In a tracking process of the contrast agent, first and second CT values of the ROI of the subject for first and second CT scans are respectively obtained. If the second CT value is no less than a target threshold, the tracking process is finished. If the second CT value is less than the target threshold, an interval for increasing the second CT value to the target threshold is determined according to the first and second CT values and a first CycleTime representing a duration between starts of the first and second scans. Then a second CycleTime is set based on the interval, and a third scan is performed according to the second CycleTime.

Abstract: An imaging system (100) includes a radiation source (708) that emits radiation that traverses an examination region (706), a radiation detector array (716) with a plurality of detectors (1104N) that detect the radiation that traverses the examination region, a dynamic bowtie filter (718) between the radiation source and the examination region, a first motor (7221) and a second motor (7222), and a controller (724). The dynamic bowtie filter includes a first half wedge (7181) and a second half wedge (7182). The first motor is in mechanical communication with the first half wedge and moves the first half wedge and the second motor is in mechanical communication with the second half wedge and moves the second half wedge. The controller independently controls the first and second motors to move the first and second half wedges.

Abstract: Various methods and systems are provided for x-ray tube conditioning for a computed tomography imaging method. In one embodiment, a scout scan may be carried out prior to a diagnostic to warmup the x-ray tube to a desired temperature for the diagnostic scan. A scout scan parameter optimizing algorithm may be used to determine scout scan parameters based on a selected patient absorbed dose range and an amount of energy to be imparted to an x-ray tube during the scout scan preceding a diagnostic scan. By using a hardening filter in the path of the x-ray beam, radiation absorbed dose of the subject being scanned may be limited to the selected patient absorbed dose range.

Abstract: Devices and optical sensor modules are provided for provide on-screen optical sensing of fingerprints by using an under-screen optical sensor module that captures and detects returned light that is emitted by the display screen for displaying images and that is reflected back by the top surface of the screen assembly. Optical collimators are provided in the under-screen optical sensor module to enhance the optical imaging performance. Techniques for reducing the environmental light in the optical sensing are provided.

Abstract: A computed tomography (CT) imaging system and method, wherein the system includes an x-ray source that is operable to emit a beam of x-rays from a focal spot and move a spot position of the focal spot. The system also includes a detector assembly that is configured to detect the x-rays attenuated by the object. At least one processing unit is configured to execute programmed instructions stored in memory. The at least one processing unit is configured to direct the x-ray source to emit different beams of the x-rays at different energy levels and to receive data from the detector assembly that are representative of detection of the x-rays emitted at the different energy levels. The at least one processing unit is also configured to direct the x-ray source to move the focal spot such that the focal spot is at different spot positions while the different beams are emitted.

Abstract: According to one embodiment, an X-ray CT apparatus includes processing circuitry. The processing circuitry acquires a plurality of discrete images at a corresponding plurality of discrete positions in a body axis direction of an object, and calculates imaging conditions corresponding to a scan range of a main scan based on the plurality of discrete images.

Abstract: A method may include obtaining first image data relating to a region of interest (ROI) of a first subject. The first image data corresponding to a first equivalent dose level may be acquired by a first device. The method may also include obtaining a model for denoising relating to the first image data and determining second image data corresponding to an equivalent dose level higher than the first equivalent dose level based on the first image data and the model for denoising. In some embodiments, the method may further include determining information relating to the ROI of the first subject based on the second image data and ecording the information relating to the ROI of the first subject.

Abstract: A radiographing system includes a mobile terminal configured to store an examination time of a subject that is based on examination-related information about the subject, a radiographing apparatus configured to take a radiation image of the subject based on the examination-related information and to store an imaging time of the radiation image, and an association unit configured to associate the radiation image with the examination-related information based on the imaging time and the examination time.

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 present invention presents a beam shaper for radiation imaging comprising a hollow beam shaper body filled with radiation attenuating gas. Radiation attenuation can be changed by adding or removing pressure to the gas or the housing containing the gas, making it suitable for use as a dynamic beam shaper in 3D radiation imaging.

Abstract: Example methods and systems are provided to perform radiation dose estimation for a target object. In one example, radiation dose estimation may include obtaining projection image data acquired using an imaging system, generating partially reconstructed volume image data based on the projection image data, and generating a partition of the projection image data. The partially reconstructed volume image data may be associated with a first region of a total radiation field. The partition may be associated with a second region of the total radiation field that is located before the first region from a direction of a radiation source. Radiation dose data may be estimated for the target object based on the partially reconstructed volume image data associated with the first region and the partition associated with the second region.

Abstract: Methods and systems are provided for adaptive scan control. In one embodiment, a method comprises: while performing a scan of a scan subject, processing acquired projection data to measure a contrast level; responsive to the contrast level increasing above a first threshold, automatically switching the scan from a first scan protocol to a second scan protocol; responsive to the contrast level decreasing below a second threshold, automatically switching the scan from the second scan protocol to the first scan protocol; and responsive to the contrast level decreasing below a third threshold, automatically ending the scan. In this way, multiple scan protocols, such as angiography and perfusion scan protocols, can be interleaved within a single scan without the use of a separate timing bolus scan.

Abstract: An X-ray CT apparatus includes a processing circuit. The processing circuit adjusts an image taking area of a subject by receiving an operation performed on a light projector provided on a gantry and further sets the adjusted image taking area as an image taking condition included in first image taking conditions; adjusts an image taking area of the subject by receiving an operator's operation via terminal equipment and further sets the adjusted image taking area as an image taking condition included in second image taking conditions; and causes the gantry to perform the image taking process on the basis of selection information selecting from between the first and the second image taking conditions as image taking conditions used for performing the image taking process.

Abstract: A dose calculation apparatus includes a specifying unit that specifies physical shape information of at least one of a body width and a body thickness of a subject using a ray-sum image generated from a plurality of medical images acquired by imaging the subject with an X-ray apparatus, an acquisition unit that acquires a correction coefficient corresponding to the physical shape information of at least one of the body width and the body thickness specified by the specifying unit from a storage unit configured to store a relationship between the physical shape information and the correction coefficient, and a calculation unit that calculates dose in accordance with a physical shape of the subject based on the correction coefficient acquired by the acquisition unit and a value representing X-ray intensity during taking of medical images.

Abstract: According to an embodiment, X-ray CT apparatus includes X-ray generator includes X-ray tube, high-voltage generator, detector, controller and circuitry. High-voltage generator generates tube voltage to be applied to X-ray tube. Detector detects X-rays irradiated from X-ray tube and transmitted through a subject. Controller controls high-voltage generator to scan the subject with first radiation dose and with second radiation dose lower than first radiation dose. Circuitry generates first image based on projection data acquired by scan at first radiation dose, generates second image based on projection data acquired by scan at second radiation dose, and displays first image and second image in common window.

Abstract: A tomography apparatus includes a data obtainer and an image processor. The data obtainer performs a tomography scan on a moving object and obtains raw data of the object The image processor reconstructs a first tomography image of the object for a first slice section in a first phase from the raw data and reconstructs a second tomography image in a second phase, which is different from the first phase, for the first slice section of the object by using the raw data. The image processor also generates motion information indicating a three-dimensional (3D) motion of the object. The second phase is a phase beyond a phase range of the raw data.

Abstract: In order to provide an X-ray CT apparatus and the like capable of obtaining an optimal X-ray dose for a dynamically changing X-ray irradiation region and reliably irradiating the X-ray irradiation region in a case where X-rays are applied with a spreading angle in a body axis direction, an X-ray CT apparatus 1 dynamically changes an X-ray irradiation region 201 for each view angle during scanning, and a system control device 124 changes a position of an analysis line 300 used to calculate an optimal tube current during scanning according to a position of the X-ray irradiation region 201 at each view angle, so as to obtain an optimal irradiation X-ray dose.

Abstract: A radiographic imaging apparatus includes: a radiographic image obtainer configured to acquire a first radiographic image of an object; and a processor configured to obtain attenuation information of the object based on the first radiographic image, determine candidate tube voltages and tube currents based on a quality of a second radiographic image to be obtained, and determine expected exposure doses corresponding to the determined candidate tube voltages and tube currents.

Abstract: An X-ray Talbot interferometer includes a source grating having a plurality of X-ray transmitting portions to transmit some X-rays from an X-ray source, a beam splitter grating configured to diffract the X-rays from the X-ray transmitting portions with a periodic structure to form interference patterns, an analyzer grating configured to block parts of the interference patterns, and a detector configured to detect X-rays from the analyzer grating. The X-ray transmitting portions of the source grating are arranged to form a periodic pattern in which spatial frequency components contained in a sideband resulting from modulation caused by the presence of an object are enhanced by superimposing the interference patterns corresponding to the respective X-ray transmitting portions. In the absence of any object, the positional relation between the periodic pattern and the grating pattern of the analyzer grating is substantially the same over the entire imaging field.

Abstract: A method and apparatus is provided to determine a reconstructed image from computed tomography projection data using iterative reconstruction with an objective function that includes modified weights. The modified weights can include, among other weight values, redundancy weights and statistical weights, which are modified to compress low-frequency components. Additionally, high-frequency components of the statistical weights can be compressed, amplified, or maintained at their current magnitude. The high-frequency components can be subject to a threshold-and-invert step, substituting an inverted value for each high-frequency component above a predefined threshold. Using the modified weights, the reconstructed image can be determined using penalized weighted least squares to minimize the objective function.

Abstract: An X-ray CT apparatus includes a table-top, an X-ray tube, a detector and a processing circuitry. The processing circuitry reconstructs a CT image based on a detection signal. The processing circuitry sets a field of view based on positions of a puncture needle and a puncture target on the CT image. The processing circuitry controls an X-ray irradiation coverage based on the field of view, the X-ray irradiation coverage being an area irradiated with the X-rays. The processing circuitry displays a CT image reconstructed in the field of view on a display, after the X-rays based on the X-rays whose irradiation coverage is controlled emitted and the detection signal is outputted.

Abstract: Among other things, one or more techniques and/or systems are described for defining imaging modes and for operating a photon counting radiation imaging system. A set of imaging modes with different counting schemes may be defined such that counting schemes will count detection events of a set of radiation events in different manners. For example, a first counting scheme may count primary detection events in a primary counter and secondary detection events in a secondary counter. A second counting scheme may count primary and secondary detection events in the primary counter. A third counting scheme may merely count detection events occurring within a primary detector cell associated with the primary counter. A fourth counting scheme may combine energy of detection events into merged energy. A selected imaging mode may be applied to the photon counting radiation imaging system in order to achieve desired image scanning characteristics (e.g., spatial resolution, dose savings, spectral ability).

Abstract: An apparatus for reducing radiation scatter in an imaging system having an operational slot for receiving an anti-scatter grid. The apparatus includes an imaging system component having at least one storage slot formed therein for selectively storing an anti-scatter grid when the grid is not in the operational slot of the imaging system. The apparatus further includes an operational slot sensor configured to detect the presence of an anti-scatter grid and/or an imaging property of a grid in the operational slot. The system allows an operator to select an appropriate anti-scatter grid for use in the imaging system from one or more anti-scatter grids that are located within the operational and/or storage slots of the imaging system.

Abstract: A method includes dynamically varying a data acquisition sample rate between at least two data acquisition sample rates during a contrast enhanced perfusion scan based on a level of contrast in image data generated during the scan. A system includes a computed tomography scanner and a console that controls the scanner based on a scan protocol, wherein the console dynamically varies a data acquisition sample rate of scanner during a contrast enhanced perfusion scan based on a level of contrast in the image data generated during the scan. A method for optimizing dose of a scan includes reducing a data acquisition sampling rate during at least a sub-portion of the scan in which a state of interest is not being scanned.

Abstract: A method and apparatus include and aligner configured to align an ordered stack of images by successively determining, for at least two already aligned images of the ordered stack, the respective misalignments with an unaligned image which is to be aligned next, and a selector configured to select from the at least two aligned images as a reference image that aligned image with which the unaligned image has the smallest amount of misalignment. The unaligned image is then aligned with the selected reference image.

Abstract: The present invention relates to calibration in X-ray phase contrast imaging. In order to remove the disturbance due to individual gain factors, a calibration filter grating (10) for a slit-scanning X-ray phase contrast imaging arrangement is provided that comprises a first plurality of filter segments (11) comprising a filter material (12) and a second plurality of opening segments (13). The filter segments and the opening segments are arranged alternating as a filter pattern (15). The filter material is made from a material with structural elements (14) comprising structural parameters in the micrometer region. The filter grating is movably arranged between an X-ray source grating (54) and an analyzer grating (60) of an interferometer unit in a slit-scanning system of a phase contrast imaging arrangement. The slit-scanning system is provided with a pre-collimator (55) comprising a plurality of bars (57) and slits (59). The filter pattern is aligned with the pre-collimator pattern (61).

Abstract: The present invention pertains to a system and method for X-ray imaging wherein a targeted fluence at the detector for projection images can be achieved at a plurality of projection angles around the imaging subject by control of exposure times implemented during image acquisition. Exposure time for a second projection image may be determined by the fluence in a first projection image, and in a third projection image by the fluence in a second projection image, where projection images are acquired within two degrees of one another. An acquisition parameter calculation can be configured to calculate acquisition parameters, such as said exposure times, to achieve the targeted fluence in projection images and can be coupled to a rotation controller that implements the acquisition parameters by controlling a relative angle between the imaging subject and X-ray image acquisition device.

Abstract: A method for dark-field imaging includes acquiring dark-field image projections of an object with an imaging apparatus that includes an x-ray interferometer, applying a pressure wave having a predetermined frequency to the object for each acquired projection, wherein the predetermined frequency is different for each projection, and processing the acquired projections, thereby generating a 3D image of the object. In other words, the method corresponds to acoustically modulated X-ray dark field tomography. An imaging system (400) includes a scanner (401) configured for dark-field imaging, the scanner including: a source/detector pair (402/408) and a subject support (416), a pressure wave generator (420) configured to generate and transmit pressure waves having predetermined frequencies, and a console (424) that controls the scanner and the pressure wave generator to acquire at least two dark-field projection of an object with different pressure waves having different frequencies applied to the object.

Abstract: An imaging system (200) is configured for grating-based DPCI. The imaging system includes a rotating gantry (204) that rotates around an examination region, a radiation source (208), supported by the rotating gantry, that emits radiation that traverses the examination region, a detector array (212), supported by the rotating gantry, that detects radiation that traverses the examination region, and an interferometer, supported by the rotating gantry, which includes a source grating (214), a phase grating (218), and an absorber grating (220). At least one of the phase grating or the absorber grating continuously translates with respect to the other during an integration period and the detector generates and outputs an electrical signal indicative of the detected radiation, wherein the electrical signal includes an absorption component, a coherence component and a phase component.

Abstract: An X-ray imaging apparatus and method are provided. The X-ray imaging apparatus according to an aspect includes an X-ray source configured to radiate X-rays onto a subject region, an X-ray detector configured to detect the radiated X-rays and obtain a plurality of frame images of the subject region, and an ROI filter located between the X-ray source and the X-ray detector, configured to move toward the X-ray source and the X-ray detector, and configured to filter the X-rays radiated from the X-ray source.

Abstract: A method for operating a computed tomograph is provided, wherein an X-ray penetrates an object from different positions, a deposition of an individual dose is effected in at least one part of the object, and an image signal is generated in the detector by way of a transmitted intensity of the X-ray, wherein exposure-related parameters for the respective different positions are individually set such that with respect to a specific position, the share of the associated individual dose is raised if a raising of the individual dose in the specific position brings about a greater improvement in the image quality than in another position, or the share of the associated individual dose is lowered if a lowering of the individual dose in the specific position brings about a smaller deterioration in the image quality than in another position, in order to lower stochastic risks for mutations and uncontrolled cell growth.

Abstract: A method for dual-energy spectra CT scanning and image reconstruction of two tomographic image datasets from a higher-energy and a lower-energy x-ray energy spectrum is disclosed. In at least one embodiment, readings are taken with the different x-ray energy spectra during the scanning; the different x-ray energy spectra are also created at least by different acceleration voltages of the x-ray source; and the spatial distribution of the scanning x-rays per x-ray energy spectrum is undertaken randomly or pseudo-randomly (in the absence of a regular pattern). With the attenuation datasets thus obtained, reconstructions of two tomographic image datasets in accordance with a least one iterative CS reconstruction method are carried out and subsequently the reconstructed tomographic image datasets are stored and/or output and/or further processed.

Abstract: A method of reconstructing an image of an object, the method including: determining, by a plurality of sensors, a waveform based on the object, wherein the plurality of sensors view the object from a plurality of directions; determining, by a pre-processing module, a plurality of measurements of the object using the waveform, wherein the plurality of measurements are arranged in a vector form; determining, by an option module, a sampling matrix, a dictionary, and a noise factor, wherein the sampling matrix represents a geometric arrangement of the plurality of sensors, and the dictionary is pre-selected by the option module; estimating, by an estimation module, a coefficient vector using the measurements, the sampling matrix, and the noise factor; and reconstructing, by a reconstruction module, the image, using the coefficient vector and the dictionary.

Abstract: The purpose of the present invention is to provide an X-ray imaging device capable of obtaining more diversified X-ray image information. To this end, the present invention comprises: an X-ray generation device for generating an X-ray; an X-ray detection device for detecting the X-ray which is generated in the X-ray generation device and penetrates the subject; and a collimator arranged between the X-ray generation device and the X-ray detection device, wherein the X-ray detection device and/or the collimator provides an X-ray imaging device configured to rotate relative to the X-ray generation device. Thus, since it is possible to adjust an X-ray detection area if necessary, the visual field of the imaging device can be adjusted such that diversified X-ray image information can be obtained.

Abstract: In an embodiment, an X-ray diagnostic apparatus includes an image capturing unit which captures an X-ray image of a subject on a tabletop, a movement mechanism which moves the tabletop and the image capturing unit relative to each other, an acquisition unit which acquires device position information on the tabletop and the image capturing unit in capturing the X-ray image, a display unit which displays the X-ray image captured by the image capturing unit, an input unit which inputs added information to be added to the X-ray image displayed on the display unit, and a management unit which manages the X-ray image captured by the image capturing unit, the device position information acquired by the acquisition unit, and the added information inputted by the input unit in association with one another.

Abstract: An imaging system includes a computed tomography (CT) acquisition unit and a processing unit. The CT acquisition unit includes an X-ray source and a CT detector configured to collect CT imaging data of an object to be imaged. The X-ray source and CT detector are configured to be rotated about the object to be imaged and to collect a series of views of the object as the X-ray source and CT detector rotate about the object to be imaged. The processing unit is operably coupled to the CT acquisition unit and configured to control the CT acquisition unit to vary a view duration for the views of the series. The view duration for a particular view defines an imaging information acquisition period for the particular view, wherein the series of views includes a first group of views having a first view duration and a second group of views having a second view duration that is different than the first view duration.

Abstract: A method and apparatus of current modulation in a computed tomography imaging system are provided. The method may include: selecting a plurality of sample points from an expected current modulation curve as approach points; establishing an actual current modulation curve, wherein an actual current value of the actual current modulation curve at an approach point approximates an expected current value of an expected current modulation curve, and a variation rate of the actual current is within an allowed range of the computed tomography imaging system; and modulating a current in an X-ray tube of the computed tomography imaging system according to the actual current modulation curve. According to the disclosure, an image valuable to the diagnosis can be obtained with the smallest radiation dose.

Abstract: A method of X-ray diffraction-based analysis for determining the structure of a crystal sample is provided. The method comprises conducting pre-experiment to collect a first set of diffraction images including reflections at corresponding intensities. The method also comprises conducting a main experiment to collect a second set of diffraction images, the diffraction images of the second set including the reflections with higher relative intensities than those produced during the first experiment, at least some of the diffraction images of the second set including topped reflections resulting from detector saturation. The method also includes a step of replacing intensities of the topped reflections from the second set of images with intensities obtained for the corresponding reflections from the first set of images.

Abstract: An X-ray CT apparatus includes a specifying unit, a setting unit, a controller, and a reconstruction unit. The specifying unit refers to exposure dose information to specify a high exposure area in an imaging area in a subject. The setting unit sets a scan condition under which a cross section of the imaging area can be imaged and under which X-rays are not directly applied to the high exposure area or another scan condition under which a cross section of the imaging area can be imaged and under which an X-ray radiation dose directly applied to the high exposure area is reduced relative to an area other than the high exposure area. The controller collects data of X-rays applied from an X-ray tube and detected by an X-ray detector under the set scan condition. The reconstruction unit reconstructs a tomographic image using the collected data of X-rays.