Abstract: A method for correcting projection images in CT image reconstruction is provided. The method may include obtaining a plurality of projection images of a subject. Each of the plurality of projection images may correspond to one of the plurality of gantry angles. The method may further include correcting a first projection image of the plurality of projection images according to a process for generating a corrected projection image. The process may include performing, based on the first projection image and a second projection image of the plurality of projection images, a first correction on the first projection image to generate a preliminary corrected first projection image. The process may also include performing, based on at least part of the preliminary corrected first projection image, a second correction on the preliminary corrected first projection image to generate a corrected first projection image corresponding to the first gantry angle.

Abstract: A system and method for generating augmented segmented image set obtain are provided. The method may include: obtaining a first image including a first anatomical structure of a first object; determining first feature data of the first anatomical structure; determining one or more first transformations related to the first anatomical structure, wherein a first transformation includes a transformation type and one or more transformation parameters related to the transformation type; applying the one or more first transformations to the first feature data of the first anatomical structure to generate second feature data of the first anatomical structure; and generating a second image based on the second feature data of the first anatomical structure.

Abstract: A radiation system may include a treatment head configured to deliver a treatment beam to an object, a first assistance assembly configured to facilitate a delivery of the treatment beam, a first imaging radiation source configured to direct a first imaging beam toward the object, a first detector configured to detect at least a portion of the first imaging beam, and a second assistance assembly configured to facilitate a delivery of the first imaging beam. The gantry may include a first gantry portion having a rotation axis and a second gantry portion located next to the first gantry portion along the rotation axis. The treatment head, the first imaging radiation source, and the first detector may be disposed on the first gantry portion. The first assistance assembly and the second assistance assembly may be housed within the second gantry portion.

Abstract: The disclosure provides a system for EGRT. The system may include a radiotherapy device for treating a subject. The radiotherapy device may include a scintillation camera that is directed at an ROI of the subject. The subject may be injected with a radioactive tracer or implanted with a radioactive marker before treatment. The ROI may undergo a physiological motion during the treatment. The system may deliver a treatment session to the subject by the radiotherapy device. During the treatment session, the system may acquire a target image of the ROI indicative of a distribution of the radioactive tracer or the radioactive maker in the ROI by the scintillation camera, and adapt a radiation beam to be delivered to the subject with respect to the physiological motion of the ROI by adjusting the radiation beam based on the target image.

Abstract: A system for equalizing a pressure in an ionization chamber of a radiation device is provided. The system may include the ionization chamber including: a chamber housing including one or more chamber walls; a chamber volume inside the chamber housing, the chamber volume being filled with a radiation sensitive material; and a pressure adjustment apparatus operably coupled to the chamber volume via at least one wall of the one or more chamber walls, the pressure adjustment apparatus being configured to equalize a first pressure of the radiation sensitive material inside the chamber volume and a second pressure of ambient air outside the chamber housing.

Abstract: The present disclosure provides systems and methods for processing a 3D image. A method may include for an orientation of the 3D image, obtaining, from the 3D image, a plurality of slices of the orientation; processing the plurality of slices of the orientation by applying a conversion model; and determining a converted 3D image of the orientation based on the plurality of processed slices of the orientation.

Abstract: A method for adaptive treatment planning is provided. The method may include obtaining a planning image volume of a subject, a treatment image volume of the subject, and a first treatment plan related to the planning image volume of the subject, each of the planning image volume and the treatment image volume including an ROI of the subject. The method may also include registering the planning image volume and the treatment image volume, and determining a first contour of the ROI in the registered planning image volume and a second contour of the ROI in the registered treatment image volume. The method may also include evaluating whether an error exists in at least one of the registration or the contour determination based on the first contour and the second contour, and determining a second treatment plan with respect to the treatment image volume based on the evaluation result.

Abstract: A method for delivering radiation treatment may include defining a preliminary trajectory including a plurality of control points. Each control point may be associated with position parameters of a gantry and a couch. The method may also include generating a treatment plan based on the preliminary trajectory by optimizing an intensity and position parameters of a collimator and MLC leaves for each control point. The method may also include decomposing the treatment plan into a delivery trajectory including the plurality of control points. Each of the plurality of control points may be further associated with the optimized intensity, the optimized position parameters of the collimator and the MLC leaves, an output rate, and a motion parameter of each of the gantry, the couch, the collimator, and the MLC leaves. The method may further include instructing a radiation delivery device to deliver the treatment plan according to the delivery trajectory.

Abstract: A system for limited view imaging is provided. The system may obtain a reference image of an object. The system may identify, from the reference image, one or more critical boundaries between a target organ of the object and one or more adjacent organs of the target organ. The system may determine an imaging angle range of the object based on the one or more critical boundaries. The system may further cause an imaging device to scan the object based on the imaging angle range, the object being in a breath-hold state during the scan.

Abstract: A radiation treatment system may include a gantry configured to rotate around an object, a treatment head moving with the gantry, a plurality of imaging radiation sources configured to emit imaging beams toward the object, and one or more first detectors configured to detect at least a portion of the imaging beams. When the treatment head is delivering a treatment beam to the object, the plurality of imaging radiation sources and the one or more first detectors may be positioned outside at least a portion of a maximum treatment radiation region so as not to interfere with the treatment beam. At least one of the plurality of imaging radiation sources and the one or more first detectors may be positioned at or near an edge of the maximum treatment radiation region.

Abstract: The present disclosure provides a method for processing projection data. The method may include obtaining a first image generated by performing a first scan to a subject by a first imaging device; determining first projection data based on the first image, the first projection data corresponding to a first area of the subject; obtaining second projection data by performing a second scan of the subject using a second imaging device, the second projection data corresponding to a second area of the subject, the first area at least partially overlapping with the second area in an overlapping area; determining registered first projection data by registering the first projection data to the second projection data with respect to the overlapping area; determining scatter component based on the registered first projection data and the second projection data, the scatter component including low-frequency scattered radiation signals.

Abstract: The present disclosure provides a method for synthesizing a projection image that represents a subject or object irradiated by X-rays from a radiation source. The method may include dividing an energy spectrum of the X-rays into one or more energy bins; determining a projection value of at least one pixel; determining a weighting coefficient corresponding to an energy bin based on a variation of the energy spectrum of the X-rays; and determining a weighted projection value of the at least one pixel based on the projection value of the at least one pixel and the weighting coefficient corresponding to the energy bin. The method may further include determining a pixel value of the at least one pixel based on the weighted projection values of the at least one pixel that correspond to all the one or more energy bins.

Abstract: A method for correcting projection images in CT image reconstruction is provided. The method may include obtaining a plurality of projection images of a subject. Each of the plurality of projection images may correspond to one of the plurality of gantry angles. The method may further include correcting a first projection image of the plurality of projection images according to a process for generating a corrected projection image. The process may include performing, based on the first projection image and a second projection image of the plurality of projection images, a first correction on the first projection image to generate a preliminary corrected first projection image. The process may also include performing, based on at least part of the preliminary corrected first projection image, a second correction on the preliminary corrected first projection image to generate a corrected first projection image corresponding to the first gantry angle.

Abstract: A system for equalizing a pressure in an ionization chamber of a radiation device is provided. The system may include the ionization chamber including: a chamber housing including one or more chamber walls; a chamber volume inside the chamber housing, the chamber volume being filled with a radiation sensitive material; and a pressure adjustment apparatus operably coupled to the chamber volume via at least one wall of the one or more chamber walls, the pressure adjustment apparatus being configured to equalize a first pressure of the radiation sensitive material inside the chamber volume and a second pressure of ambient air outside the chamber housing.

Abstract: The present disclosure is related to systems and methods for isocenter calibration. The method includes providing a phantom including a first member and a second member with a fixed position relationship. The method includes acquiring, using a first device, at least one first image of the first member of the phantom. The method includes determining, based on the at least one first image, a first position relationship between a first isocenter of the first device and the first member. The method includes acquiring, using a second device, at least one second image of the second member of the phantom. The method includes determining, based on the at least one second image and the fixed position relationship, a second position relationship between a second isocenter of the second device and the first member. The method includes determining, based on the first position relationship and the second position relationship, a third position relationship between the first isocenter and the second isocenter.

Abstract: A system for limited view imaging is provided. The system may obtain a reference image of an object. The system may identify, from the reference image, one or more critical boundaries between a target organ of the object and one or more adjacent organs of the target organ. The system may determine an imaging angle range of the object based on the one or more critical boundaries. The system may further cause an imaging device to scan the object based on the imaging angle range, the object being in a breath-hold state during the scan.

Abstract: The method may include obtaining a first set of imaging data affording a sagittal view relating to a subject and a first couch supporting the subject. The first couch may have a plurality of first positions reflected in the first set of imaging data as a first conformation. The method may also include determining a displacement field associated with a first set of imaging data with respect to the reference conformation based on the first conformation and a reference conformation. The method may further include adjusting the first set of imaging data with respect to the reference conformation based on the displacement field. In some embodiments, the method may include obtaining an image of the subject with respect to the reference conformation based on the adjusted first set of imaging data.

Abstract: A system, medium, and method including obtaining a plurality of positions for multiple components defined by a plan; obtaining a set of constraints that express limitations for the multiple components at the plurality of positions, the constraints being applicable to a plan where the multiple components synchronously change their positions with time to traverse a prescribed sequence of the plurality of positions, at least one of the multiple components being further constrained to change its position over time by staying within a predefined tolerance to a predefined smooth function of position over time between different positions; determining a trajectory of position and a minimum duration in which the multiple components completely synchronously traverse the prescribed sequence of positions while satisfying the constraints for the multiple components; and generating a record of the determined trajectory of position and the minimum duration for the plurality of components.

Abstract: A radiation system may include a treatment head configured to deliver a treatment beam to an object, a first assistance assembly configured to facilitate a delivery of the treatment beam, a first imaging radiation source configured to direct a first imaging beam toward the object, a first detector configured to detect at least a portion of the first imaging beam, and a second assistance assembly configured to facilitate a delivery of the first imaging beam. The gantry may include a first gantry portion having a rotation axis and a second gantry portion located next to the first gantry portion along the rotation axis. The treatment head, the first imaging radiation source, and the first detector may be disposed on the first gantry portion. The first assistance assembly and the second assistance assembly may be housed within the second gantry portion.

Abstract: A radiation system is provided. The radiation system may include a bore accommodating an object, a rotary ring, a first radiation source and a second radiation source mounted on the rotary ring and a processor. The first radiation source may be configured to emit a first cone beam toward a first region of the object. The second radiation source may be configured to emit a second beam toward a second region of the object, the second region including at least a part of the first region. The processor may be configured to obtain a treatment plan of the object, the treatment plan including parameters associated with radiation segments. The processor may be further configured to control an emission of the first cone beam and/or the second beam based on the parameters associated with the radiation segments to perform a treatment and a 3-D imaging simultaneously.