Abstract: A system and method of adapting a radiation therapy treatment plan. The method includes the acts of preparing a treatment plan for a patient, acquiring images of the patient, performing deformable registration of the images, acquiring data relating to a radiation dose delivered to the patient, applying a biological model relating the radiation dose delivered and a patient effect, and adapting the radiation therapy treatment plan based on the deformable registration and the biological model.

Abstract: An ion radiation therapy machine provides a steerable beam for treating a tumor within the patient where the exposure spot of the beam is controlled in width and/or length to effect a flexible trade-off between treatment speed, accuracy, and uniformity.

Abstract: A small field radiation therapy machine having an aperture diameter of 30 cm or less provides improved ray definition for specialized treatment of portions of the human body such as head a breast.

Abstract: A modulator for radiation therapy provides modulation of an area beam to decrease treatment time. Separate channels passing modulated “beamlets” are possible by spacing the channels such that spreading of the beams and multiple angles of treatment eliminate cold spots. The space between the channels allows well-defined channel walls and space for modulator mechanisms.

Abstract: A phantom for heavy ion radiation therapy provides characterization of an ion beam that may enter but not exit from the phantom. The phantom may include multiple materials and multiple spatially dispersed ion detectors to obtain signals that may be fit to known beam curves to accurately characterize the location and other parameters of Bragg peak of a given ion beam within a patient.

Abstract: An x-ray computed tomography system uses a broad area x-ray emitter and detector to allow both in plane and out of plane x-ray projections not restrained to spiral or helical scans.

Abstract: A high efficiency radiation detector employs longitudinally extending converter elements receiving longitudinally propagating radiation to produce high-energetic electrons received by detector structures in interstitial spaces. The secondary electron generation in this architecture allows great freedom in selection of converter materials and thickness. A variety of detector mechanisms may be used including ionization-type detectors or scintillation-type detector.

Abstract: The present invention provides a system and method of using current but incomplete data to prepare an approximated complete image of a patient potentially undergoing radiation therapy. A limited patient image, such as that obtained from a CT scan is fused with a complete image of the same area using image registration techniques. The fused image is converted to sinogram data. This data is compared to sinogram data corresponding to the limited patient image to determine what data exists beyond the scope of the limited sinogram. Any additional data is added to the limited data sinogram to obtain a complete sinogram. This is reconstructed into an image that approximates the complete image that would have been taken at the time the limited image was obtained.

Abstract: The present invention provides methods of using current but incomplete data to prepare an approximated complete image of a patient potentially undergoing radiation therapy. A complete image of the patient is fused or aligned with a limited patient image using image registration techniques. The aligned image is converted to sinogram data. This sinogram data is compared to sinogram data corresponding to the limited patient image to determine what data exists beyond the scope of the limited sinogram. Any additional data is added to the limited data sinogram to obtain a complete sinogram. This complete sinogram is then reconstructed into an image that approximates the complete image that would have been taken at the time the limited image was obtained.

Abstract: A high efficiency radiation detector employs longitudinally extending converter elements receiving longitudinally propagating radiation to produce high-energetic electrons received by detector structures in interstitial spaces. The secondary electron generation in this architecture allows great freedom in selection of converter materials and thickness. A variety of detector mechanisms may be used including ionization-type detectors or scintillation-type detector.

Abstract: A method of compensating for unexpected changes in the size, shape, and/or position of a patient in the delivery of radiation therapy. An image of a patient is used to prepare a treatment plan for the irradiation of a tumor or the like, shown in the image. A second image of a patient includes a visual representation of the tumor and sensitive structures wherein any combination of the size, shape, or position of the tumor or sensitive structures is different from any combination of the size, shape, or position of the visual representation of the tumor or sensitive structures in said first image. The radiation treatment is adjusted to more closely conform the treatment plan to the new size, shape, or position of the tumor as shown in said second image. This adjustment can occur before, during, or after the radiation delivery and can be used to define trade-offs that exist for the delivery.

Abstract: A method of calibration and verification of radiotherapy systems deduced radiation beam fluence profiles from the radiation source from a complete model of an extended radiation phantom together with dose information from a portal imaging device. The improved beam fluence profile characterization made with an iterative modeling which includes scatter effects may be used to compute dose profiles in the extended phantom or a patient who has been previously characterized with a CT scan. Deviations from the expected beam fluence profile can be used to detect patient misregistration.

Abstract: Reduced dose megavoltage CT images are obtained using low flux data resulting from leakage through modulating shutters and/or collected by other means and augmented by incomplete high flux data collected during radiation therapy. The ability to construct tomographic projection sets from significantly varying flux rate data is provided by the use of air scans windowed to account for variations in mechanical leaf movement. These methods are also provide a means of imaging the patient entirely during radiation therapy treatments without any additional scan time.

Abstract: A method for determining a radiation treatment plan for a radiotherapy system providing multiple individual rays of intensity modulated radiation iteratively optimized the fluence of an initial set of such rays by a function that requires knowledge of only the prescribed dose and the dose resulting from the particular ray fluences. In this way, the need to store individual dose distributions of each ray are eliminated.

Abstract: A method of compensating for unexpected changes in the size, shape, and/or position of a patient in the delivery of radiation therapy. An image of a patient is used to prepare a treatment plan for the irradiation of a tumor or the like, shown in the image. A second image of a patient includes a visual representation of the tumor and sensitive structures wherein any combination of the size, shape, or position of the tumor or sensitive structures is different from any combination of the size, shape, or position of the visual representation of the tumor or sensitive structures in said first image. The radiation treatment is adjusted to more closely conform the treatment plan to the new size, shape, or position of the tumor as shown in said second image. This adjustment can occur before, during, or after the radiation delivery and can be used to define trade-offs that exist for the delivery.

Abstract: The present invention provides a system and method of using current but incomplete data to prepare an approximated complete image of a patient potentially undergoing radiation therapy. A limited patient image, such as that obtained from a CT scan is fused with a complete image of the same area using image registration techniques. The fused image is converted to sinogram data. This data is compared to sinogram data corresponding to the limited patient image to determine what data exists beyond the scope of the limited sinogram. Any additional data is added to the limited data sinogram to obtain a complete sinogram. This is reconstructed into an image that approximates the complete image that would have been taken at the time the limited image was obtained.

Abstract: In radiotherapy, a high quality imaging array may be placed after the patient and opposite the radiation source to be used during radiation treatment to verify operation of a shutter system or similar device and/or to compute dose delivered to the patient. A model of the patient may be used and inverted in order to estimate values of energy fluence prior to absorption by the patient and overlapping of the various radiation beams passing through the patient. A test pattern of shutter excitation to illuminate a single ray at a time provides a simple method of obtaining the necessary model. The dose from this test pattern may be subtracted from the subsequent radiation treatment so as to provide limited or no increase in total dose to the patient.

Abstract: A method of calibration and verification of radiotherapy systems deduced radiation beam fluence profiles from the radiation source from a complete model of an extended radiation phantom together with dose information from a portal imaging device. The improved beam fluence profile characterization made with an iterative modeling which includes scatter effects may be used to compute dose profiles in the extended phantom or a patient who has been previously characterized with a CT scan. Deviations from the expected beam fluence profile can be used to detect patient misregistration.

Abstract: Radiotherapy controlling, treatment sinograms may be directly modified to correct for real time motion of patients or portions of patients resulting from physiological or other activity. Precalculated partial sinograms representing treatments of portions of a patient may be assembled to obtain a treatment sinogram for the entire patient without delay from conventional planning software. The partial sinograms are modified as representations of their corresponding portions and manipulated to conform to the particular dimensions of an actual patient. This constructed sinogram may be used directly or as a starting point for iterative optimization.

Abstract: A method of calibration and verification of radiotherapy systems deduced radiation beam fluence profiles from the radiation source from a complete model of an extended radiation phantom together with dose information from a portal imaging device. The improved beam fluence profile characterization made with an iterative modeling which includes scatter effects may be used to compute dose profiles in the extended phantom or a patient who has been previously characterized with a CT scan. Deviations from the expected beam fluence profile can be used to detect patient misregistration.