Abstract: Methods and devices for cutting a three-dimensional image are disclosed. According to one example of the methods, a region of interest may be selected from an original three-dimensional image. A mesh model of the region of interest may be constructed. Then, distance field information and a shape index characteristic value of each mesh point in the mesh model may be obtained. A set of initiation points and a set of termination points may be obtained by splitting the mesh model according to the distance field information. Afterward, a mixed cost value of each mesh point may be obtained according to the distance field information, the shape index characteristic value and an image value of each mesh point. In this way, a cutting path may be determined from the set of initiation points and the set of termination points according to the mixed cost value.

Abstract: Methods, systems, and machine-readable storage mediums for reconstructing a PET image are provided. In one aspect, a method includes: determining a plurality of LORs associated with multiple-coincidence data in coincidence data detected by a PET device through scanning, obtaining a respective line integral value along each of the LORs according to a time difference between two single events corresponding to the LOR, allocating the multiple-coincidence data to the LORs according to the respective line integral values of the LORs to obtain respective multiple allocation data on the LORs, correcting respective double-coincidence data in the coincidence data corresponding to each of the LORs based on the respective multiple allocation data on the LOR to obtain data of the LOR, and reconstructing an image according to the data of each of the LORs.

Abstract: A method of computed tomography (CT) perfusion imaging includes: obtaining perfusion data by using a CT device to scan a present perfusion subject; performing calculations of the perfusion data by using two perfusion calculation methods to obtain perfusion parameters of each of said two perfusion calculation methods as initial perfusion parameters of each of said two perfusion calculation methods; performing calculations by using the initial perfusion parameters based on weights of said two perfusion calculation methods to obtain target perfusion parameters; and forming a target perfusion image of the present perfusion subject according to the target perfusion parameters.

Abstract: Method of correcting PET image attenuation and PET/MRI devices are provided. In one aspect, an MRI image of a subject is segmented to obtain respective MRI sub-images corresponding to attenuation units of the subject, respective pseudo CT sub-images corresponding to the MRI sub-images are obtained based on an MRI-CT atlas, the respective pseudo CT sub-images corresponding to the MRI sub-images are spliced to obtain a pseudo CT image corresponding to the MRI image, and attenuation correction is performed for a PET image of the subject according to the pseudo CT image, wherein the PET image and the MRI image are obtained through a same scan process for the subject.

Abstract: Methods, systems, and machine-readable storage mediums for clock synchronizing among detectors in a clock synchronizing configuration are provided. An example clock synchronizing method includes: providing a clock of a preset frequency in each of N modules to be synchronized, coupling every two adjacent modules of the modules by a transmission line of the same length, N being an odd number, selecting two different modules from the modules as two reference modules respectively, controlling each of the reference modules to transmit a synchronizing signal to the other modules, determining a clock error between every two modules having the same transmission distance from the reference module according to a moment of the synchronizing signal reaching each of the other modules, selecting a calibrating module from the modules, and implementing clock synchronization between each of the modules and the calibrating module according to the respective clock errors associated with the two reference modules.

Abstract: A method and device for controlling a linear accelerator as well as a linear accelerating system are provided according to examples of the present disclosure. In an example, a first component of the linear accelerator is controlled to move according to a motion instruction; when it is detected that the first component reaches a first position, the first component is controlled to pause moving, and a second component of the linear accelerator is controlled to move in a preset direction; when it is detected that the second component reaches a second position, the second component is controlled to stop moving, and the first component is controlled to continue to move according to the motion instruction.

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 and a device for processing metal artifacts in a CT image are provided. In an example, the method includes: a first image is obtained before a metal probe is intervened; second raw data and a second image corresponding to the second raw data are obtained after the metal probe is intervened; a third image of a metal region in the second image is obtained; channels corresponding to the metal region are determined; CT values of the metal region in the second image are set to a preset value to obtain a model image and model raw data corresponding to the model image; data at the channels in the second raw data is replaced with data at the channels in the model raw data to obtain a replaced second raw data; and based on the replaced second raw data and the third image, a target image is obtained.

Abstract: Methods and devices for reconstructing a magnetic resonance image, and a non-transitory machine readable storage medium are provided. In an example, the method includes: obtaining a previous image; for each of channels, collecting k-space data of the channel by a partial sampling technology, generating original k-space data of the channel by mapping the previous image into k-space of the channel, and obtaining residue k-space data of the channel by subtracting the original k-space data of the channel from the k-space data of the channel; reconstructing a residue image with the residue k-space data of each of the channels by taking sparsity of the residue image as a constraint term and a difference between virtual residue k-space data of the channel and the residue k-space data of the channel as a data fidelity term; and obtaining a reconstructed magnetic resonance image by adding the residue image to the previous image.

Abstract: Methods, devices and a machine-readable storage medium for denoising a Computed Tomography (CT) image are provided. In one aspect, a method of denoising a CT image includes: generating an original CT image according to raw data which is obtained by scanning a subject, where a pixel count of the original CT image is greater than a preset target pixel count; obtaining a denoised image by denoising the original CT image; and obtaining a target image as a CT image of the subject by compressing the denoised image to the preset target pixel count based on an interpolation algorithm.

Abstract: An example two-path symmetrical-output adjustable power supply is provided, including a switching power supply module, a positive adjustment module, a negative adjustment module and a first operational amplifier. The switching power supply module is coupled to a DC power supply and the first operational amplifier and configured to output a positive voltage and a negative voltage in common-ground and equal in absolute value according to a feedback control based on a reference voltage and the output voltage of the first operational amplifier. The positive adjustment module is coupled to the positive voltage and configured to output a positive output voltage of the adjustable power supply according to a feedback control based on a given voltage and the positive output voltage. The negative adjustment module is coupled to the negative voltage and configured to output a negative output voltage of the adjustable power supply according to the positive output voltage.

Abstract: A method and apparatus for preheating a bulb tube of medical equipment is provided. The method includes: selecting a scanning condition which satisfies an equipment calibration condition, as a preheating condition for the bulb tube, from scanning conditions used by the medical equipment; selecting a new preheating condition if an accumulated thermal capacity according to selected preheating conditions is smaller than a target thermal capacity, until the accumulated thermal capacity reaches the target thermal capacity, wherein the accumulated thermal capacity indicates a sum of a thermal capacity estimated to be generated when the bulb tube is preheated according to the selected preheating conditions, and the target thermal capacity indicates a thermal capacity required to complete the preheating of the bulb tube; preheating the bulb tube according to selected preheating conditions and executing an equipment calibration corresponding to each of the preheating conditions during the bulb tube preheating.

Abstract: In an example, a method for air calibration is provided. An initial scanning condition may be generated from a subject scanning sequence of medical equipment, wherein, the subject scanning sequence is generated when a subject is scanned by the medical equipment to obtain an image of the subject and recorded in association with a subject ID uniquely identifying the subject. An air calibration scanning condition may be obtained by correcting the initial scanning condition. An air calibration may be performed on the medical equipment according to the air calibration scanning condition to generate air calibration data.

Abstract: A method and device for X-ray scanning based on dose, comprising: receiving an X-ray dose for scanning set for a region of a subject to be scanned, selecting a scanning and reconstructing technology combination according to said pre-set X-ray dose for scanning wherein the demanded X-ray dose of the selected scanning and reconstructing technology combination satisfies said pre-set X-ray dose for scanning, and scanning said region and implementing a reconstruction accordingly with the selected scanning and reconstructing technology combination to obtain a resultant scanning image.

Abstract: In an example, a method and apparatus for obtaining an image mask is provided. After a magnitude image and a phase image of a to-be-processed image is obtained, magnitude coherent data of each pixel point in the magnitude image and phase coherent data of each pixel point in the phase image may be calculated. Then, a binarization threshold processing may be performed on the magnitude coherent data of each pixel point in the magnitude image to obtain a magnitude image mask. A binarization threshold processing may be performed on the phase coherent data of each pixel point in the phase image to obtain a phase image mask. In this way, an image mask of the to-be-processed image may be obtained by using the magnitude image mask and the phase image mask.

Abstract: Methods, devices, and apparatus, including computer programs encoded on a computer storage medium for reconstructing an image are provided. An example method includes: acquiring Computed Tomography (CT) projection data of a subject, determining an image cutoff frequency Fimg according to a CT image matrix size for reconstructing a CT image and an imaging field of view size, obtaining a convolution kernel and a cutoff frequency Fker of the convolution kernel, using the convolution kernel as a reconstruction convolution kernel when Fker<Fimg; adjusting Fker to a product of a preset value k and Fimg and truncating the convolution kernel to obtain a portion of the convolution kernel having a cutoff frequency no more than the adjusted Fker as the reconstruction convolution kernel when Fker?Fimg, and reconstruct the CT image with the CT projection data and the reconstruction convolution kernel by using a convolution back-projection algorithm.

Abstract: A method for upgrading medical equipment is disclosed. The method may include: according to a first target upgrading identification in a software upgrading package, determining a first target equipment number corresponding to the first target upgrading identification. The table of upgrading identifications can include association between upgrading identifications and equipment numbers of the medical equipment. The method further includes sending the software upgrading package to a first target medical equipment corresponding to the first target equipment number to allow the first target medical equipment to upgrade itself according to the software upgrading package.

Abstract: A background correction method for CT scan data is provided. A background collection may be performed to collect a first background data set and background data before a CT scan. The CT scan may then be performed to collect one or more CT scan data sets, and status information for collecting each of the CT scan data sets. A second background collection may additionally be performed to collect a second background data set after the CT scan, and status information for collecting the second background data set may also be recorded. The first background data set, the second background data set and corresponding status information may then be used to obtain a background data set for collecting each of the CT scan data sets. The corresponding background data set may be removed from each of the CT scan data set to obtain a background-corrected CT scan data set.

Abstract: A method of calibrating time in a Positron Emission Computed Tomography (PET) device includes determining a rising edge slope of an electrical signal corresponding to a photon which is detected by a detector of the PET device when the PET device is used to scan a part of a subject to be examined. The method includes determining a time shift corresponding to the rising edge slope based on a correspondence between the rising edge slope and the time shift; calibrating time information of the photon based on the time shift; and reconstructing a PET image of the part of the subject to be examined based on the calibrated time information of the photon.

Abstract: Methods and apparatus, including computer programs encoded on a computer storage medium, for image reconstruction are provided. According to an example of the methods, an image reconstruction may be performed to generate a first set of reconstructed data with a first set of projection data comprising a plurality of first projection data each corresponding to a respective projection angle of a plurality of projection angles. A second set of projection data comprising second projection data for each projection angle may be generated with the first set of reconstructed data. The first set of projection data may be corrected based on a shifting distance between the first projection data and the second projection data for each projection angle. Then, a second set of reconstructed data may be generated with the corrected first set of projection data, and a reconstructed image may be generated according to the second set of reconstructed data.