Systems and methods for determining beam asymmetry in a radiation treatment system using electronic portal imaging devices (EPIDs) without implementation of elaborate and complex EPID calibration procedures. The beam asymmetry is determined based on radiation scattered from different points in the radiation beam and measured with the same region of interest ROI of the EPID.

Systems and method for generating and executing volumetric modulated arc therapy (“VMAT”) plans are provided. In some aspects, the method includes receiving a representation of a subject comprising information related to target and non-target volumes of interest, and generating an objective function based on the representation of the subject, wherein the objective function accounts for dynamic collimator rotation. The method also includes performing an iterative optimization process, using the objective function, to generate a dynamic collimator VMAT plan, and generating a report in accordance with the dynamic collimator VMAT plan.

Methods of treatment trajectory optimization for radiotherapy treatment of multiple targets include determining beam's eye view (BEV) regions and a BEV region connectivity manifold for each target group of a plurality of target groups separately. The information contained in the BEV regions and the BEV region connectivity manifolds for all target groups is used to guide an optimizer to find optimal treatment trajectories. To improve the visibility of insufficiently exposed voxels of planning target volumes (PTVs), a post-processing step may be performed to enlarge certain BEV regions, which are considered for exposing during treatment trajectory optimization.

Methods of beam angle optimization for intensity modulated radiotherapy (IMRT) treatment include determining beam's eye view (BEV) regions and a BEV region connectivity manifold by evaluating dose response of each region of interest for each vertex in a delivery coordinate space (DCS). The information contained in the BEV regions and the BEV region connectivity manifold is used to guide an optimizer to find optimal field geometries in the IMRT treatment. To improve the visibility of insufficiently exposed voxels of planning target volumes (PTVs), a post-processing step may be performed to enlarge certain BEV regions, which are considered for exposing during treatment trajectory optimization.

A method of measuring a rotational position of an assembly with circumferential ferromagnetic teeth includes applying an excitation signal for a cycle to an actuator, the cycle causing a first rotational displacement of a first ferromagnetic tooth from a first rotational position to a second rotational position and a second rotational displacement of a second ferromagnetic tooth from the second rotational position to a third rotational position. The method further includes measuring a plurality of first signal outputs from a magnetoresistive sensor during the cycle; determining one or more signal offset values based on the plurality of first signal outputs; applying the signal excitation for a portion of a second cycle to the actuator; measuring second signal outputs from the magnetoresistive sensor; generating corrected signals by modifying the second signal outputs with the signal offset values; and, based on the corrected signals, determining a rotational position of the assembly.

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.

Presented systems and methods enable efficient and effective robust radiation treatment planning and treatment, including analysis of dose rate robustness. In one embodiment, a method comprising accessing treatment plan information, accessing information corresponding to an uncertainty associated with implementation of the radiation treatment plan, and generating a histogram, wherein the histogram conveys a characteristic of the treatment plan including an impact of the uncertainty on the characteristic. The histogram can be a dose rate volume histogram and can be utilized to test a degree of robustness of a treatment plan (e.g., including allowance for uncertainty scenarios, etc.). The uncertainty can be associated with potential variation associated with tolerances (e.g., radiation system/machine performance tolerance, patient characteristic tolerances, etc.) and set up issues (e.g., variation in initial system/machine set up, variation patient setup/position, etc.)

Presented systems and methods enable efficient and effective robust radiation treatment planning and treatment, including analysis of dose rate robustness. In one embodiment, a method comprising accessing treatment plan information, accessing information corresponding to an uncertainty associated with implementation of the radiation treatment plan, and generating a histogram, wherein the histogram conveys a characteristic of the treatment plan including an impact of the uncertainty on the characteristic. The histogram can be a dose rate volume histogram and can be utilized to test a degree of robustness of a treatment plan (e.g., including allowance for uncertainty scenarios, etc.). The uncertainty can be associated with potential variation associated with tolerances (e.g., radiation system/machine performance tolerance, patient characteristic tolerances, etc.) and set up issues (e.g., variation in initial system/machine set up, variation patient setup/position, etc.)

A device for implanting radiotherapy seeds in a tumor. The device includes a delivery tube having a distal end designed to enter the tumor, and defining an internal channel and an elongate applicator carrying one or more radiotherapy seeds each having a length of at least 1 millimeter, the applicator passing through the internal channel of the delivery tube. When a distal end of the elongate applicator is near a distal end of the delivery tube, it assumes an angle relative to an axis of the delivery tube, such that seeds ejected from the elongate applicator enter the tumor at an angle relative to the axis of the delivery tube.

A method for planning a scan path for intraoperative radiation therapy may comprise acquiring a plurality of images of a region of interest through an auxiliary scanning component, establishing a 3D model of the region of interest based on the plurality of images of the region of interest, determining a radiation therapy volume based on the 3D model of the region of interest, and planning a scan path for a radiation therapy component to scan the radiation therapy volume.