Abstract: The present disclosure relates to systems and methods for pulse parameter modulation. The systems may perform the methods to obtain information related to a treatment plan; determine a backward window based on the information related to the treatment plan, within which one or more radiation pulses have been transmitted; determine backward information associated with the backward window based on the information related to the treatment plan and the backward window; determine a forward window based on the information related to the treatment plan, within which one or more radiation pulses are to be transmitted; determine forward information associated with the forward window based on the information related to the treatment plan, the backward information, and the forward window; and determine one or more pulse parameters of the forward window based on the forward information.

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: A method and system for using in a two-modality apparatus. The two-modality apparatus comprises a couch with a table top, a first modality unit and a second modality unit. A second image of a target portion of an object when the table top is at a second working position of the second modality unit may be acquired. A second sag of the table top at a second measurement point of the table top according to the second image may be determined based on the image. A difference between a first sag of the table top at a first measurement point of the table top and the second sag may be estimated based on the second sag and standard data. The standard data provides a relationship relating to a sag of the table top positioned between the first modality unit and second modality unit.

Abstract: A radiation therapy medical apparatus is disclosed. The medical apparatus comprises: a base; a cylindrical gantry, peripherally and rotatably supported by the base; a radiation therapy assembly, comprising an arm and a radiation head, wherein one end of the arm is fixed to a first position on a first side of the gantry and the other end thereof is extended outwardly, and the radiation head is fixed to the other end of the arm; an imaging assembly, mounted to a second side of the gantry opposite to the first side, and configured to be a first balanced weight part for balancing the radiation therapy assembly; and a counterbalance, fixed to the second side of the gantry, and configured to cooperate with the imaging assembly to prevent the gantry from turnover under action of the radiation therapy assembly and configured to dynamically balance with the radiation therapy assembly with respect to a rotation axis of the gantry.

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 system includes determination of a first sub-matrix of a projection matrix which describes a geometrical relationship between points of a three-dimensional coordinate system of the imaging system and points of a two-dimensional coordinate system of an image detector, determination of a second sub-matrix of the projection matrix, where the first and second sub-matrixes comprise a decomposition of the projection matrix, conversion of a first point of the two-dimensional coordinate system to a first point of the three-dimensional coordinate system based on the first and second sub-matrixes, determination of an updated first sub-matrix of an updated projection matrix, where the updated projection matrix describes a second geometrical relationship between points of the three-dimensional coordinate system and points of the two-dimensional coordinate system, and conversion of a second point of the two-dimensional coordinate system to a second point of the three-dimensional coordinate system based on the updated fi

Abstract: The present disclosure provides a method for computed tomography (CT) image reconstruction. The method may include obtaining a plurality of projection images of a subject. The plurality of projection images may be generated according to scan data acquired by a CT scanner at a plurality of gantry angles, each of the plurality of projection images corresponding to one of the plurality of gantry angles. The method may also include determining attenuation information of the plurality of projection images. The method may further include reconstructing a CT image of the subject by simultaneously solving correction coefficients of the plurality of projection images such that a difference between estimated attenuation information of the plurality of projection images and the attenuation information of the plurality of projection images is minimized.

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 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.

Abstract: A method for generating a radiation treatment plan is provided. The method may include determining a set of one or more optimization goals for radiation delivery by a therapeutic radiation delivery apparatus. The method may also include determining a plan for radiation delivery from a radiation source of the therapeutic radiation delivery apparatus. The radiation source may be capable of continuously rotating around a subject. The plan may include a plurality of radiation segments. Each radiation segment may be characterized by at least one parameter selected from a start angle, a stop angle, a two-dimensional segment shape, or a segment MU value such that the plurality of radiation segments satisfy the set of one or more optimization goals by superimposing at least two radiation segments from at least two different rotations into a target volume of the subject.

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 system includes determination of a first sub-matrix of a projection matrix which describes a geometrical relationship between points of a three-dimensional coordinate system of the imaging system and points of a two-dimensional coordinate system of an image detector, determination of a second sub-matrix of the projection matrix, where the first and second sub-matrixes comprise a decomposition of the projection matrix, conversion of a first point of the two-dimensional coordinate system to a first point of the three-dimensional coordinate system based on the first and second sub-matrixes, determination of an updated first sub-matrix of an updated projection matrix, where the updated projection matrix describes a second geometrical relationship between points of the three-dimensional coordinate system and points of the two-dimensional coordinate system, and conversion of a second point of the two-dimensional coordinate system to a second point of the three-dimensional coordinate system based on the updated fi

Abstract: A radiation treatment device may include a first dosimeter and a second dosimeter. Quantum efficiency of the first dosimeter may be lower than quantum efficiency of the second dosimeter. A method for monitoring beam energy may include receiving a first signal generated by a first dosimeter, receiving a second signal generated by a second dosimeter, receiving a third signal generated by the first dosimeter and receiving a fourth signal generated by the second dosimeter. The first signal and the second signal may be associated with a first radiation beam. The second signal and the fourth signal may be associated with a second radiation beam. The method may also include determining whether there is a difference between the beam energy of the first radiation beam and the second radiation beam based on at least one of the first signal, the second signal, the third signal or the fourth signal.

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 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 radiation system may include a treatment assembly including a first radiation source, a second radiation source, and a first radiation detector. The first radiation source may be configured to deliver a treatment beam covering a treatment region of the radiation system, and the treatment region may be located in a bore of the radiation system. The second radiation source may be configured to deliver a first imaging beam covering a first imaging region of the radiation system, and may be mounted rotatably on a first side of the treatment assembly. The first radiation detector may be configured to detect at least a portion of the first imaging beam, and may be mounted rotatably on a second side of the treatment assembly. The treatment assembly, the second radiation source, and the first radiation detector may be positioned such that the treatment region is addressable for the radiation system.

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 method and system for using in a two-modality apparatus. The two-modality apparatus comprises a couch with a table top, a first modality unit and a second modality unit. A second image of a target portion of an object when the table top is at a second working position of the second modality unit may be acquired. A second sag of the table top at a second measurement point of the table top according to the second image may be determined based on the image. A difference between a first sag of the table top at a first measurement point of the table top and the second sag may be estimated based on the second sag and standard data. The standard data provides a relationship relating to a sag of the table top positioned between the first modality unit and second modality unit.

Abstract: The present disclosure relates to systems and methods for pulse parameter modulation. The systems may perform the methods to obtain information related to a treatment plan; determine a backward window based on the information related to the treatment plan, within which one or more radiation pulses have been transmitted; determine backward information associated with the backward window based on the information related to the treatment plan and the backward window; determine a forward window based on the information related to the treatment plan, within which one or more radiation pulses are to be transmitted; determine forward information associated with the forward window based on the information related to the treatment plan, the backward information, and the forward window; and determine one or more pulse parameters of the forward window based on the forward information.

Abstract: A method for radiotherapy may include generating an electrical impedance tomography (EIT) image of a patient. The method may also include generating a first image. The method may further include determining an EIT feature of the EIT image. The method may also include determining a position relationship between the EIT image and the first image. The method may further include locating an anatomical structure of interest (ASI) of the patient based on the position relationship. The method may further include delivering radiation to the ASI of the patient.