The present disclosure generally relates to a multi-leaf collimator. The multi-leaf collimator may include a set of leaves installed in a cavity, each leaf of the set of leaves having a length along a first direction. At least a portion of the set of leaves may extend beyond the cavity along the first direction. The set of leaves may be arranged along a second direction, the second direction being different from the first direction. A length of a target leaf of the set of leaves may be less than a length of a reference leaf of the set of leaves. The target leaf may be located in an end portion of the set of leaves along the second direction. The length of the set of leaves may conform to the shape of a maximum therapeutic radiation field.

A method of making a treatment plan with a treatment planning system and radiotherapy system are provided. The method includes: acquiring a preset dose distribution scheme; generating at least one radiation dose distribution scheme to be used with the treatment planning system, wherein the treatment plan system is adapted to at least one of beam energy of the radiotherapy system, a size of a collimator of the radiotherapy system, a radiation angle and radiation time of the radiotherapy system; and comparing the at least one radiation dose distribution scheme to be used with the preset dose distribution scheme, and determining, among the at least one radiation dose distribution scheme, a radiation dose distribution scheme that is the closest to the preset dose distribution scheme to make the treatment plan.

It is provided a method for generating a plurality of treatment plans for radiation therapy, each treatment plan specifying weights for a plurality of geometrically defined fluence elements. Each weight defines an amount of radiation fluence, to thereby provide radiation dose to a target volume. The method is performed in a treatment planning system and comprises the steps of: generating a first set of treatment plans; determining a subset of the fluence elements, based on the first set of treatment plans; and generating a second set of at least two treatment plans, wherein the treatment plans only contain weights for the subset of fluence elements.

The present disclosure provides systems and methods for adjusting a multi-leaf collimator (MLC) in a treatment process according to a treatment plan or a portion thereof. The MLC may include at least one closed leaf pair in the treatment process. The method may include: for each of the at least one closed leaf pair, determining an offset for the closed leaf pair; and causing the at least one closed leaf pair to move based on the determined at least one offset before or during the treatment process.

The present disclosure may provide a collimator assembly. The collimator assembly may include a multi-leaf collimator (MLC) situated in a first plane and at least one block situated in a second plane different from the first plane. The MLC may include at least one first group of leaves and at least one second group of leaves opposing each other and being moveable along a first direction. One of the at least one block may be located at a position corresponding to an end of the at least one first group of leaves. Projection of one of the at least one block along a second direction may partially overlap projection of the at least one first group of leaves along the second direction.

Systems, devices, and methods for imaging-based calibration of radiation treatment couch position compensations.

After accessing optimization information for a particular patient and for a particular radiation treatment platform, a control circuit generates an optimized radiation treatment plan by processing the optimization information using direct-aperture-optimization that includes fluence-based sub-optimization. By one approach, the control circuit includes the fluence-based sub-optimization in at least some, but not necessarily all, iterations of the direct-aperture-optimization. By one approach, the control circuit is configured to include only a few iterations of the fluence-based sub-optimization when including the fluence-based sub-optimization in at least some, but not necessarily all, iterations of the direct-aperture-optimization.

The present disclosure provides a system and method for X-ray imaging. The method of calculating scatter in an X-ray image may include forming a modulated X-ray image. The method of forming the modulated X-ray image may include acquiring X-rays through a collimator module and an imaged object in sequence to generate an X-ray image group; the acquisition may be performed during a movement of the collimator module in a first direction and the X-ray image group may include a plurality of X-ray images acquired at different times during the movement of the collimator; extracting sub-zones from the plurality of X-ray images in the X-ray image group; combining the sub-zones in the first direction to form the modulated X-ray image. In the present disclosure, an intensity distribution of the X-rays may be adjusted flexibly using a collimator without adding any extra hardware. In addition, scatter components in the X-ray images may be calculated to eliminate the scatter in the X-ray images finally.

The present disclosure relates to a motion guidance assembly for guiding the motion of a collimator device. The motion guidance assembly may include a first pair of flexible plates connected to the collimator device. The first pair of flexible plates may be deformable in a direction perpendicular to an opening of the collimator device. A deformation of the first pair of flexible plates may guide the motion of the collimator device based on a driving force.

A radiation treatment session is initiated to deliver a therapeutic radiation beam from a therapeutic radiation source to a target. One or more X-ray radiation sources are caused to deliver an imaging radiation beam from the one or more X-ray radiation sources through the target to one or more X-ray detectors to acquire imaging data associated with the target during therapeutic radiation beam delivery. One or more volumetric images are constructed using the acquired imaging data.