Abstract: A radiation therapy system comprising a therapeutic radiation system (e.g., an MV X-ray source, and/or a linac) and a co-planar imaging system (e.g., a kV X-ray system) on a fast rotating ring gantry frame. The therapeutic radiation system and the imaging system are separated by a gantry angle, and the gantry frame may rotate in a direction such that the imaging system leads the MV system. The radiation sources of both the therapeutic and imaging radiation systems are each collimated by a dynamic multi-leaf collimator (DMLC) disposed in the beam path of the MV X-ray source and the kV X-ray source, respectively. In one variation, the imaging system identifies patient tumor(s) positions in real-time. The DMLC for the imaging radiation source limits the kV X-ray beam spread to the tumor(s) and/or immediate tumor regions, and helps to reduce irradiation of healthy tissue (e.g., reduce the dose-area product).

Abstract: Disclosed herein are methods for patient setup and registration for the irradiation of target tissue regions. A method for positioning a patient for radiation therapy may include acquiring an image of a first patient target region and a second patient target region. A first set of patient position-shift vectors may be calculated based on the acquired image and a treatment planning image of the first patient target region. A second set of patient position-shift vectors may be calculated based on the acquired image, a treatment planning image of the second patient target region, and the first set of patient position-shift vectors. The patient may be positioned according to the first set of patient position-shift vectors in a first location. The patient may be moved to a second location and positioned according to the second set of patient position-shift vectors.

Abstract: Described herein are multi-leaf collimators that comprise leaf drive mechanisms. The leaf drive mechanisms can be used in binary multi-leaf collimators used in emission-guided radiation therapy. One variation of a multi-leaf collimator comprises a pneumatics-based leaf drive mechanism. Another variation of a multi-leaf collimator comprises a spring-based leaf drive mechanism having a spring resonator.

Abstract: Systems and methods for shuttle mode radiation delivery are described herein. One method for radiation delivery comprises moving the patient platform through the patient treatment region multiple times during a treatment session. This may be referred to as patient platform or couch shuttling (i.e., couch shuttle mode). Another method for radiation delivery comprises moving the therapeutic radiation source jaw across a range of positions during a treatment session. The jaw may move across the same range of positions multiple times during a treatment session. This may be referred to as jaw shuttling (i.e., jaw shuttle mode). Some methods combine couch shuttle mode and jaw shuttle mode. Methods of dynamic or pipelined normalization are also described.

Abstract: Described herein are methods for beam station delivery of radiation treatment, where the patient platform is moved to a series of discrete patient platform locations or beam stations that are determined during treatment planning, stopped at each of these locations while the radiation source rotates about the patient delivering radiation to the target regions that intersect the radiation beam path, and then moving to the next location after the prescribed dose of radiation (e.g., in accordance with a calculated fluence map) for that location has been delivered to the patient.

Abstract: Described here are systems, devices, and methods for imaging and radiotherapy procedures. Generally, a radiotherapy system may include a radiotransparent patient platform, a radiation source coupled to a multi-leaf collimator, and a detector facing the collimator. The radiation source may be configured to emit a first beam through the collimator to provide treatment to a patient on the patient platform. A controller may be configured to control the radiotherapy system.

Abstract: Disclosed herein are variations of megavoltage (MV) detectors that may be used for acquiring high resolution dynamic images and dose measurements in patients. One variation of a MV detector comprises a scintillating optical fiber plate, a photodiode array configured to receive light data from the optical fibers, and readout electronics. In some variations, the scintillating optical fiber plate comprises one or more fibers that are focused to the radiation source. The diameters of the fibers may be smaller than the pixels of the photodiode array. In some variations, the fiber diameter is on the order of about 2 to about 100 times smaller than the width of a photodiode array pixel, e.g., about 20 times smaller. Also disclosed herein are methods of manufacturing a focused scintillating fiber optic plate.

Abstract: Disclosed herein are methods and devices for the acquisition of positron emission (or PET) data in the presence of ionizing radiation that causes afterglow of PET detectors. In one variation, the method comprises adjusting a coincidence trigger threshold of the PET detectors during a therapy session. In one variation, the method comprises adjusting a gain factor used in positron emission data acquisition (e.g., a gain factor used to multiply and/or shift the output(s) of a PET detector(s)) during a therapy session. In some variations, a method for acquiring positron emission data during a radiation therapy session comprises suspending communication between the PET detectors and a signal processor of a controller for a predetermined period of time after a radiation pulse has been emitted by the linac.

Abstract: Disclosed herein are methods for radiotherapy treatment plan optimization for irradiating one or more target regions using both an internal therapeutic radiation source (ITRS) and an external therapeutic radiation source (ETRS). One variation of a method comprises iterating through ITRS radiation dose values and ETRS radiation dose values to attain a cumulative dose that meets prescribed dose requirements. In some variations, an ITRS is an injectable compound that has a targeting backbone and a radionuclide, and images acquired using an imaging compound that has the same targeting backbone as the injectable compound can be used to calculate the radiation dose deliverable using the injectable ITRS, and also to calculate firing filters for delivering radiation using a biologically-guided radiation therapy (BGRT) system. Image data acquired from a previous treatment session may be used to adapt the dose provided by an ITRS and/or ETRS for a future treatment session.

Abstract: Disclosed herein are systems and methods for adapting and/or updating radiotherapy treatment plans based on biological and/or physiological data and/or anatomical data extracted or calculated from imaging data acquired in real-time (e.g., during a treatment session). Functional imaging data acquired at the time of radiation treatment is used to modify a treatment plan and/or dose delivery instructions to provide a prescribed dose distribution to patient target regions. Also disclosed herein are methods for evaluating treatment plans based on imaging data acquired in real-time.

Abstract: Disclosed herein are systems and methods for guiding the delivery of therapeutic radiation using incomplete or partial images acquired during a treatment session. A partial image does not have enough information to determine the location of a target region due to, for example, poor or low contrast and/or low SNR. The radiation fluence calculation methods described herein do not require knowledge or calculation of the target location, and yet may help to provide real-time image guided radiation therapy using arbitrarily low SNR images.

Abstract: An apparatus comprising a radiation source, coincident positron omission detectors configured to detect coincident positron annihilation emissions originating within a coordinate system, and a controller coupled to the radiation source and the coincident positron emission detectors, the controller configured to identify coincident positron annihilation emission paths intersecting one or more volumes in the coordinate system and align the radiation source along an identified coincident positron annihilation emission path.

Abstract: Disclosed herein are systems and methods for monitoring calibration of positron emission tomography (PET) systems. In some variations, the systems include an imaging assembly having a gantry comprising a plurality of positron emission detectors. A housing may be coupled to the gantry, and the housing may include a bore and a radiation source holder spaced away from a patient scan region within the bore. A processor may be configured to receive positron emission data from the positron emission detectors and to distinguish the positron emission data from the radiation source holder and from the patient scan region. A fault signal may be generated when the positron emission data from the radiation source holder exceeds one or more threshold parameters or criteria.

Abstract: A radiation therapy system comprising a therapeutic radiation system (e.g., an MV X-ray source, and/or a linac) and a co-planar imaging system (e.g., a kV X-ray system) on a fast rotating ring gantry frame. The therapeutic radiation system and the imaging system are separated by a gantry angle, and the gantry frame may rotate in a direction such that the imaging system leads the MV system. The radiation sources of both the therapeutic and imaging radiation systems are each collimated by a dynamic multi-leaf collimator (DMLC) disposed in the beam path of the MV X-ray source and the kV X-ray source, respectively. In one variation, the imaging system identifies patient tumor(s) positions in real-time. The DMLC for the imaging radiation source limits the kV X-ray beam spread to the tumor(s) and/or immediate tumor regions, and helps to reduce irradiation of healthy tissue (e.g., reduce the dose-area product).

Abstract: Systems and methods for shuttle mode radiation delivery are described herein. One method for radiation delivery comprises moving the patient platform through the patient treatment region multiple times during a treatment session. This may be referred to as patient platform or couch shuttling (i.e., couch shuttle mode). Another method for radiation delivery comprises moving the therapeutic radiation source jaw across a range of positions during a treatment session. The jaw may move across the same range of positions multiple times during a treatment session. This may be referred to as jaw shuttling (i.e., jaw shuttle mode). Some methods combine couch shuttle mode and jaw shuttle mode. Methods of dynamic or pipelined normalization are also described.

Abstract: This application relates to methods for delivering radiation to a positron-emitting target within a subject under continuous PET guidance. Instead of directing radiation at a collinear path along each detected positron line-of-response (LOR), the methods generally include detecting a pattern of LORs that intersect the target. In response to the pattern, radiation may be delivered along paths that are not necessarily collinear to any of the LORs. Methods for further modifying radiation delivery as well as the detected LOR population are also described.

Abstract: Disclosed herein are systems and methods for real-time monitoring of patient position and/or location during a radiation treatment session. Images acquired of a patient during a treatment session can be used to calculate the patient's position and/or location with respect to the components of the radiation therapy system. One variation of a radiation therapy system includes a circular gantry with a rotatable ring coupled to a stationary frame, a therapeutic radiation source mounted on the rotatable ring, and a patient-monitoring imaging system mounted on the rotatable ring. The patient-monitoring system may have one or more image sensors or cameras disposed on the rotatable ring within a bore region of the radiation therapy system, and may be configured to acquire image data as the ring rotates.

Abstract: Described herein are methods for beam station delivery of radiation treatment, where the patient platform is moved to a series of discrete patient platform locations or beam stations that are determined during treatment planning, stopped at each of these locations while the radiation source rotates about the patient delivering radiation to the target regions that intersect the radiation beam path, and then moving to the next location after the prescribed dose of radiation (e.g., in accordance with a calculated fluence map) for that location has been delivered to the patient.

Abstract: Disclosed herein are variations of megavoltage (MV) detectors that may be used for acquiring high resolution dynamic images and dose measurements in patients. One variation of a MV detector comprises a scintillating optical fiber plate, a photodiode array configured to receive light data from the optical fibers, and readout electronics. In some variations, the scintillating optical fiber plate comprises one or more fibers that are focused to the radiation source. The diameters of the fibers may be smaller than the pixels of the photodiode array. In some variations, the fiber diameter is on the order of about 2 to about 100 times smaller than the width of a photodiode array pixel, e.g., about 20 times smaller. Also disclosed herein are methods of manufacturing a focused scintillating fiber optic plate.

Abstract: Disclosed herein are methods and devices for the acquisition of positron emission (or PET) data in the presence of ionizing radiation that causes afterglow of PET detectors. In one variation, the method comprises adjusting a coincidence trigger threshold of the PET detectors during a therapy session. In one variation, the method comprises adjusting a gain factor used in positron emission data acquisition (e.g., a gain factor used to multiply and/or shift the output(s) of a PET detector(s)) during a therapy session. In some variations, a method for acquiring positron emission data during a radiation therapy session comprises suspending communication between the PET detectors and a signal processor of a controller for a predetermined period of time after a radiation pulse has been emitted by the linac.