Abstract: Some embodiments include a particle source, an RF power source, an accelerator waveguide, and an imaging device. The particle source is to generate a first injector current and a second injector current, the first injector current being less than the second injector current. The RF power source is to generate first RF power at a first pulse rate and second RF power at a second pulse rate, the first pulse rate being greater than the second pulse rate. The accelerator waveguide is to accelerate a first electron beam based on the first injector current and the first RF power and to accelerate a second electron beam based on the second injector current and the second RF power, and the imaging device is to acquire an image based on the first electron beam. The second electron beam may be used to deliver treatment radiation to a patient.

Abstract: A dynamic IMRT scheme. A RAD ON/RAD OFF cycle is an IMRT segment. Every set of opposing leaves in the collimator produces an IMRT profile or track. According to such an embodiment, at least one of the opposing leaves moves toward the other to produce the given track. When a track is complete, the opposing leaves remain together until the end of the segment. The dose rate remains constant during the segment.

Abstract: A radiation therapy device (2) includes a programmable power source (300) and controller (302) that monitor an injected current level and controls heater voltage in response thereto. The heater voltage is reduced in predetermined increments without affecting the beam profile.

Abstract: A radiation therapy device (2) includes a programmable power source (300) and controller (302) that monitor an injected current level and controls heater voltage in response thereto. The heater voltage is reduced in predetermined increments without affecting the beam profile.

Abstract: A dynamic IMRT scheme. A RAD ON/RAD OFF cycle is an IMRT segment. Every set of opposing leaves in the collimator produces an IMRT profile or track. According to such an embodiment, at least one of the opposing leaves moves toward the other to produce the given track. When a track is complete, the opposing leaves remain together until the end of the segment. The dose rate remains constant during the segment.

Abstract: Aspects for verifying an accessory beam limiting device position for a radiotherapy treatment session are described. Included in a system aspect is a radiotherapy treatment device, the radiotherapy treatment device including an accessory holder. A beam limiting device for establishing a treatment area, the beam limiting device held in the accessory holder, is also included, along with a first controller for controlling the radiotherapy device and performing a treatment plan. A second controller positions the beam limiting device according to the treatment plan, wherein performance of the treatment plan by the first controller depends on provision of an accessory code to the first controller. The accessory code includes a resistor-pair combination value.

Abstract: A method and system in accordance with the present invention uses the existing hardware and divides the treatment port dose into segments. In between each segment the field, with respect to the beam, would be translated, and the leaf positions would be adjusted to maintain the tumor contour. By integrating the above-identified methodology with a hardware system, accurate conformal radiation therapy is provided while minimizing leakage. In addition, through the present invention, higher dose rates can be provided while not appreciably affecting treatment time.

Abstract: The present invention relates to a system and method for calibrating a radiation therapy device, such as a collimator. A method for calibrating a collimator according to an embodiment of the present invention is presented. The method comprises moving a leaf of a collimator; determining whether a distance between the leaf and a line approximately equals a predetermined measurement; and associating the predetermined measurement with a collimator specific count if the distance between the leaf and the line approximately equals the predetermined measurement.

Abstract: According to an embodiment of the present invention, an isocenter of an image may be found by using a multi-leaf collimator. According to this embodiment, a center leaf is projected into the center of the x-ray field with all other leaves retracted. An image is acquired. A line through the center of the center leaf is identified. This line is also a line through isocenter. Another method according to an embodiment of the present invention for finding isocenter uses an accessory. The accessory according to an embodiment of the present invention includes a metal marker in the center of the accessory with metal markers interspersed away from the center at a predetermined interval. An image may be acquired through the accessory, with the patient on the table. The resulting image may be analyzed to identify the position of the metal markers to determine isocenter.

Abstract: A system and method for radiation therapy delivery. Known errors are compensated for by applying an offset factor to the dose at the start of the beam cycle. According to one embodiment of the invention, a dosimetry controller is configured to provide the offset connection and sense radiation on (RAD ON) and monitor the dose rate at the beginning of the beam cycle.

Abstract: Method and system aspects for utilizing portal images in a virtual wedge treatment during radiation treatment by a radiation-emitting device are described. In a method aspect, and system for achieving same, the method includes utilizing an image dose with a static jaw gap position to initiate a virtual wedge treatment with portal imaging. The method further includes continuing with the virtual wedge treatment from a reduced jaw gap position with a dynamic dose and dynamic jaw positioning. In addition, the virtual wedge treatment in completed with a static dose in the static jaw gap position.

Abstract: A radiation therapy device (2) configured to receive a signal indicative of one or more of a patient's physiological parameters. The signal controls a gating, whereby a phase of an RF pulse (1002) and an injector pulse (1006) are varied so as to inhibit X-ray production without affecting injector or RF amplitudes.

Abstract: A system and method for radiation therapy delivery. A radiation therapy device according to the present invention is configured to monitor for instantaneous dose rate and accumulated dose even during conditions when the high voltage modulator is decoupled. If either the dose rate or the accumulated dose exceed a predetermined threshold, an interlock will be asserted to shut down the radiation treatment device.

Abstract: A system and method for radiation therapy delivery. Prior to the delivery of the actual treatment, a run up is executed in order to stabilize the RF system. The run up is accomplished by initiating the triggers with the injector and RF pulses out of phase so that the electrons, for example, in the accelerating waveguide do not get accelerated even though the RF system is being pulsed. The RF warm up period during which the injector and RF pulses are out of phase, ends at RAD ON (Radiation On) with the injector pulse being phase-shifted to coincide in time with the RF pulse thereby resulting in the production of electron beam pulses. Following the application of this run up period, precise and rapid disabling and enabling of the treatment beam between IMRT fields can be accomplished. The electron injection is phase-shifted in and out without affecting either the injector or the RF pulse amplitudes, thereby allowing transitions between a stable RAD ON beam and no beam between one pulse and the next.

Abstract: A system and method for radiation therapy delivery. Known delays are compensated for by applying a compensation factor to the dose at the start of the beam cycle. According to one embodiment of the invention, a dosimetry controller is configured to sense radiation on (RAD ON) and monitor the dose rate at the beginning of the beam cycle. The dosimetry controller then multiplies the dose rate by a compensation factor. Thus, for each beam cycle, the dosimetry controller resolves the magnitude of the lost dose rate data and compensates each segment accordingly.