Abstract: A CT pilot image acquisition method and a CT device are provided. The method may include: performing a helical scan on a predetermined area to be scanned, so as to obtain scanning data; reconstructing a tomographic image based on the scanning data; performing, at a predetermined positioning angle, a parallel beam projection on the tomographic image by using a virtual parallel X-ray beam, so as to obtain projection data; and re-binning a CT pilot image at the predetermined positioning angle based on the projection data. Parallel beam projection is adopted to process the tomographic image, to obtain a pilot image without geometric distortions. The obtained pilot image can reflect an anatomical structure of human body accurately.

Abstract: A method for modulating x-ray radiation dose in CT scan is disclosed. The method may include: acquiring x-ray attenuation information of each Z position within a planned scanning sequence for a scan region of a subject from data of a finished scanning sequence for the subject; and then, based on the acquired x-ray attenuation information, performing dose modulation with respect to the XY scanning profile at each Z position within the planned scanning sequence. The finished scanning sequence can be an axial and/or helical scanning sequence for a scan region wholly or partially same as the scan region and has been performed earlier. The Z position may include a position in Z direction extending from head to foot of the subject or conversely. The XY scanning profile may include a scanning profile of the subject which is vertical to Z direction.

Abstract: A method for restoring CT scan data is disclosed. The method may comprise: building a data collecting model with respect to a specific direction of a detector based a response curve of the detector. In some examples, the specific direction can indicate a channel direction and a slice direction of the detector. During a CT scanning, based on the data collecting model, X-ray intensity values detected by the detectors in the specific direction can be acquired. A function can be determined such that it satisfies the data collecting model, a continuity condition and a boundary condition, An X-ray intensity value can be obtained by substituting the coordinate value of a point in the specific direction into the function.

Abstract: Disclosed are a method and apparatus for improving image reconstruction speed, to improve the image reconstruction speed by acquiring optimal thread configurations of execution units under different scanning conditions.

Abstract: A method and apparatus of image compensation are provided. The method may include: calculating an overlapping position between two adjacent scannings; obtaining two images at the overlapping position of the two adjacent scannings, and calculating mutual information of the two images by using a three dimensional non-rigid registration method; and acquiring a corresponding transformational matrix when the mutual information reaches a threshold, and compensating one of the two scans which needs to be compensated by using the transformational matrix. Images at the overlapping position of two neighboring scannings can be used to find a motion law at an identical z position of the two adjacent scannings and to obtain a corresponding match factor. Thus inconsistence of images caused by a patient's movement can be compensated.

Abstract: A method for correcting a CT scan image is provided. A target image including a target region to be corrected is extracted from an original CT scan image. A target projection range corresponding to the target region is obtained by orthographically projecting the target image, and target projection data within the target projection range is corrected. Noise of the corrected target projection data is adjusted to generate noise-adjusted target projection data to improve noise consistency between target region and the rest of the CT scan image. A corrected CT scan image is reconstructed based on the noise-adjusted target projection data.

Abstract: A method for calculating a motion vector field (MVF) in a reconstructed CT scan image, comprises: determining a region of interest (ROI) based on a vessel centreline in a first reconstructed CT scan image, wherein a motion vector field (MVF) for the ROI is to be calculated; determining at least two time control points for calculating the MVF; calculating a motion level factor of the ROI; calculating motion amounts of the MVF corresponding to each of the time control points; determining the direction of the MVF of the ROI; and calculating the MVF of the ROI according to the motion level factor, the motion amounts of the MVF corresponding to each of the time control points and the direction of the MVF.

Abstract: A method for controlling an X-ray dose of a CT scan includes: setting an initial X-ray dose; performing a first CT scan with the initial X-ray dose to obtain an initial scan image; setting a region of interest (ROI) in the initial scan image; calculating an subsequent X-Ray dose with image values of the ROI in the initial scan image; perform an additional CT scan with the calculated subsequent X-Ray dose to obtain an average image; before receiving an end instruction, repeating the following operations: recalculating an subsequent X-Ray dose with image values of the ROI in the average image and performing an additional CT scan with the calculated subsequent X-Ray dose to obtain a new average image; and saving the average image when receiving the end instruction.

Abstract: A method for reconstructing a CT scan image, comprising: performing a first scan to acquire a first projection data, wherein the first scan is a scan that a subject is covered by a low dose X-ray beam in an axial plane; performing a second scan to acquire a second projection data, wherein the second scan is a scan that a target portion of the subject is covered by a high dose X-ray beam in the axial plane; determining a data filling point in the second projection data, wherein the data filling point is located in a truncated region; and filling the data filling point in the second projection data with a data from the first projection data which corresponds to the data filling point; and reconstructing a second scan image based on the filled second projection data.

Abstract: A method and device for adjusting a monitored region in a tracking scan, comprising: selecting a best match of a positioned image from tracked image(s) as a monitored layer image so as to reduce position deviation of the monitored layer image with respect to the positioned image in a direction perpendicular to a plane on which the positioned image is located; and adjusting a position of a second monitored region on the monitored layer image according to a position of a corresponding first monitored region selected from the positioned image so as to reduce position deviation of the second monitored region with respect to the first monitored region in a plane parallel to the plane on which the positioned image is located.

Abstract: The disclosure includes: judging whether a center line of an object to be scanned is deviated from a rotation axis of a gantry of a CT scanning device; determining a first distance by which the center line of the object to be scanned is deviated from the rotation axis in a case that the center line of the object to be scanned is deviated from the rotation axis; determining according to the first distance a second distance by which the shape filter is to be translated in each projection angle; and controlling the shape filter to make it translate by the second distance in each corresponding projection angle.

Abstract: A method and a device for dose modulated X-ray scanning, comprising: setting a target image quality standard for a scanning region, determining a reference data level for the scanning region, calculating a theoretical X-ray scanning dose for the scanning region according to the target image quality standard and the reference data level, calculating the X-ray attenuation difference between each data level corresponding to the scanning region and the reference data level according to the theoretical X-ray scanning dose, determining any one of the data levels corresponding to the scanning region, which X-ray attenuation difference with the reference data level is higher than a threshold as a target to be de-noised, and performing a noise reduction for the target to be de-noised.

Abstract: Disclosed are a method and apparatus for improving image reconstruction speed, to improve the image reconstruction speed by acquiring optimal thread configurations of execution units under different scanning conditions.

Abstract: A method and a device for providing reference information for a scan protocol are provided. The method includes: obtaining first basic information and a first pilot image of a patient to be scanned as index information; retrieving a second pilot image that matches the index information from a preset scan protocol database; and outputting a second pilot image, and a second reconstructed image and a second scan protocol in the preset scan protocol database which correspond to the second pilot image as reference information. If the second pilot image matches the index information, the physical condition of a scanned patient corresponding to the second pilot image is similar to that of the patient to be scanned, and the second pilot image, and the second reconstructed image and the second scan protocol in the preset scan protocol database which correspond to the second pilot image are outputted as reference information.

Abstract: A method includes: collecting projection data and recording electrocardiogram data when computed tomographic scanning is performed on a patient, selecting, from the projection data and based on the electrocardiogram data, first projection data related to each cardiac pixel in a same phase, and reconstructing, based on the first projection data, an image of the related cardiac pixel, to obtain a cardiac image; determining, based on the electrocardiogram data, a reconstruction phase of each reconstruction pixel in a first reconstruction region, where the first reconstruction region is an image region selected along the patient's head-to-foot direction from the cardiac image; and selecting, based on the reconstruction phase of each reconstruction pixel and from the projection data, second projection data related to the reconstruction pixel in the reconstruction phase, and reconstructing, based on the second projection data, an image of the reconstruction pixel.

Abstract: A method for setting a scanning protocol and an apparatus thereof are provided. The method includes: creating a plain film positioning image; receiving a point or a line or a region of interest on the plain film positioning image input by an operator; generating a region to be matched, based on the point or the line or the region of interest; determining whether there is pre-stored reference image having a matching degree greater than a preset threshold by comparing pre-stored reference images with the region to be matched; obtaining a reference image in the case that the reference image has a matching degree greater than the preset threshold; selecting a scanning protocol corresponding to the reference image based on a preset correspondence between reference images and scanning protocols; and completing a setting of the scanning protocol in the case that there is the scanning protocol corresponding to the reference image.

Abstract: A method for collecting multi-energy CT data is provided. A method of reconstruction from multi-energy CT scan is further provided, in which data collection is performed on the first-class object at voltage values of m sampling points of the first-class voltage varied periodically, to obtain n sets of multi-energy first-class scan data {yi}; and a data collection is performed on a double-cylinder correction phantom at the voltage values of m sampling points to obtain combination coefficients, and thus obtaining corresponding combination coefficients Cifirstand Cisecondcorresponding to the case that the first-class scan data is collected in the ith projection angle at the first-class voltage; and the image vectors Xfirst and Xsecond are obtained by calculating a minimum value of the difference between the first-class scan data {yi} and the combination projection data CifirstPi*Xfirst+CisecondPi*Xsecond.

Abstract: A scanning system and an image display method are provided, the method including: implementing a scanning process to obtain scanning data; converting the scanning data into image data; implementing an identification process and a segmentation process to the image data to obtain position and direction information of an interventional device; and calculating a first set of imaging parameters corresponding to a first image display mode based on the obtained position and direction information of the interventional device, and implementing real-time image display based on the first set of imaging parameters. Position and direction of interventional devices may be determined accurately. Further, multiple display modes are available, which may provide an accurate and full range image display.

Abstract: Image reconstruction method and device for tilted helical scan are provided. The method includes: acquiring data generated by the tilted helical scan; calculating a ray channel parameter and a slice number corresponding to each pixel position based on a geometric relationship that a ray of the tilted helical scan emitting from a ray source to a detector intersects with a pixel; and performing image reconstruction by using a three-dimensional helical back-projection method based on the acquired data, and the ray channel parameter and the slice number corresponding to each pixel position. With the method and device, there is no need to correct the raw data, which ensures the accuracy of the data, and the artifact is avoided, which ensures the accuracy of the reconstructed image.

Abstract: A method and a device for balancing a CT gantry device are provided. The method includes: obtaining a fluctuation chain of pulses generated in one revolution of the CT gantry and obtained when the CT gantry collects data; obtaining an eccentric angle of a center of mass according to the fluctuation chain, and calculating a magnitude of imbalance; and adjusting weight at a weight counterbalancing position according to the eccentric angle and the magnitude of imbalance, to locate the center of mass at the rotation center. The device includes a data collection unit for collecting a fluctuation chain, and a processor for obtaining an eccentric angle of a center of mass, and calculating a magnitude of imbalance; and the processor adjusts weight at the weight counterbalancing position according to the eccentric angle and the magnitude of imbalance, to locate the center of mass at the rotation center.