Collimators and range adjusters for particle therapy systems

Abstract

An exemplary system includes a particle accelerator that generates a particle beam to treat a patient and a carrier having an opening, the opening including a first opening and a second opening. The carrier is made of a material that inhibits the delivery of the particle beam, and the carrier is located between the particle accelerator and the patient. The control system is configured to control the movement of the particle beam to the first opening so that at least a portion of the particle beam can reach the patient, change the energy of the particle beam while the particle beam remains stationary at the first opening, and control the movement of the particle beam from the first opening to the second opening. The exemplary system also includes a range adjuster that includes at least some boron carbide.

Description

[0001] Cross-references to related applications

[0002] This application claims priority to and the benefit of U.S. Provisional Patent Application No. 62 / 815,721, filed on March 8, 2019, entitled “Delivery Of Radiation By Column.” This application claims priority to and the benefit of U.S. Provisional Patent Application No. 62 / 853,387, filed on May 28, 2019, entitled “Energy Degrader Including Boron Carbide.” This application claims priority to and the benefit of U.S. Provisional Patent Application No. 62 / 889,825, filed on August 21, 2019, entitled “Generating A Treatment Plan.” This application claims priority to and the benefit of U.S. Provisional Patent Application No. 62 / 889,861, filed on August 21, 2019, entitled “Collimator For A Particle Therapy System.” The contents of U.S. Provisional Patent Applications 62 / 815,721, 62 / 853,387, 62 / 889,825, and 62 / 889,861 are incorporated herein by reference. Technical Field

[0003] The present disclosure generally relates to collimators and range adjusters for particle therapy systems. Background Art

[0004] Particle therapy systems use accelerators to generate particle beams to treat diseases, such as tumors. In operation, particles are accelerated in orbits within a cavity in the presence of a magnetic field and removed from the cavity through an extraction channel. A magnetic field regenerator generates a magnetic field shock near the outside of the cavity to distort the pitch and angle of certain orbits so that they move toward, and ultimately into, the extraction channel. A particle beam consisting of particles leaves the extraction channel.

[0005] The scanning system is down-beam of the particle beam of the extraction channel. Down-beam in this example means closer to the radiation target relative to the extraction channel. The scanning system moves the particle beam relative to the radiation target to expose various portions of the radiation target to the particle beam. For example, to treat a tumor, the particle beam can be scanned over different portions of the tumor to expose different portions to radiation.

[0006] The scanning system may include a range adjuster to change the energy of the particle beam, thereby changing the different depths of the tumor affected by the particle beam. A collimator may be used to shape the particle beam. For example, a collimator may allow a portion of the particle beam to reach the patient while preventing a different portion of the particle beam from reaching the patient. Summary of the invention

[0007] An example system includes a particle accelerator that generates a particle beam to treat a patient and a carrier having an opening including a first opening and a second opening. The carrier includes a material that inhibits the delivery of the particle beam, and the carrier is located between the particle accelerator and the patient. The control system is configured to control the movement of the particle beam to the first opening so that at least a portion of the particle beam can reach the patient, to change the energy of the particle beam when the particle beam remains stationary at the first opening, and to control the movement of the particle beam from the first opening to the second opening. The example system can include one or more of the following features, alone or in combination.

[0008] The opening may include an array of holes, the first opening being a first hole and the second opening being a second hole. The opening may include an array of slots, the first opening being a first slot and the second opening being a second slot.

[0009] The system may include a range adjuster between the particle accelerator and the patient. The range adjuster may include a structure configured to move into and out of the particle beam path so as to change the energy of the particle beam. The control system may be configured to control the movement of the structure into or out of the particle beam path to change the energy of the particle beam. The structure may include plates for changing the energy of the particle beam as the particle beam passes through one or more plates. The plates may be or include boron carbide. The particle accelerator may include a superconducting magnet having a conductive coil. The control system may be configured to change the current through the conductive coil to change the energy of the particle beam.

[0010] The control system can be configured to change the energy of the particle beam so that the particle beam treats the columnar portion of the target in the patient through the first opening before the particle beam moves from the first opening to the second opening. When the particle beam is in the first opening, the particle beam can deliver a radiation dose of more than 1 Gray per second to the target for a duration of less than 5 seconds. When the particle beam is in the first opening, the particle beam can deliver a radiation dose of 20 Gray per second to 100 Gray per second to the target for a duration of 10 milliseconds to 5 seconds. When the particle beam is in the first opening, the particle beam can deliver a radiation dose of 40 Gray per second to 120 Gray per second to the target with a duration of less than 5 seconds. When the particle beam is in the first opening, the particle beam can deliver a radiation dose to the target at any ultra-high dose rate. When the particle beam is in the first opening, the particle beam can deliver a radiation dose of greater than 100 Gray per second, greater than 200 Gray per second, greater than 300 Gray per second, greater than 400 Gray per second, or greater than 500 Gray per second to the target with a duration of less than 500ms, a duration between 10ms and 5s, or a duration of less than 5s.

[0011] The openings may include apertures, the first opening being a first aperture and the second opening being a second aperture. Controlling movement of the particle beam toward the first aperture and then toward the second aperture may include centering the particle beam at the first aperture and then centering the particle beam at the second aperture.

[0012] After the particle beam has moved from the first opening to the second opening, the particle beam may no longer move to the first opening.

[0013] The system may include a scanning magnet having a conductive coil. The scanning magnet may be used to generate a magnetic field to affect the movement of the particle beam. The control system may be configured to affect the magnetic field by changing the current passing through the conductive coil of the scanning magnet, thereby controlling the movement of the particle beam. The system may include a track on which the carrier is mounted for moving within the beam field of the particle beam. The motor may be configured to move the carrier along the track. The control system may be configured to control the motor to move the carrier along the track based on the movement of the particle beam. The system may include a ridge filter to expand the Bragg peak of the particle beam.

[0014] The system may include a track on which the carrier is mounted for movement. The motor may be configured to move the carrier along the track in response to one or more commands from the control system. The control system may be configured to change the energy of the particle beam when the particle beam remains stationary at the second opening, and control the movement of the particle beam from the second opening to a plurality of additional openings, wherein the particle beam remains stationary for a period of time at each of the plurality of additional openings while the energy of the particle beam is changed at each opening.

[0015] An exemplary collimator includes a carrier having one or more openings. The carrier may be or include a material that inhibits the transport of a particle beam. Each of the one or more openings may have an immutable size and shape. Each of the one or more openings may have a variable size and / or shape. Some of the one or more openings may have a variable size and / or shape, and some of the one or more openings may have an immutable size and / or shape. The collimator may include a track on which the carrier is mounted for movement within a beam field of a particle beam. The motor is configured to move the carrier along the track based on the movement of the particle beam. The exemplary collimator may include one or more of the following features, alone or in combination.

[0016] One or more openings may be or include an array of holes. One or more openings may be or include a single linear array of holes. One or more openings may be or include one or more slots extending through the longitudinal dimension of the carrier. One or more openings may be or include a single slot extending through the longitudinal dimension of the carrier. The carrier may be made of or include at least one of nickel, brass, or tungsten. The motor may be responsive to commands from a control system to move the carrier along the track.

[0017] The carrier may be a first carrier. The collimator may include a second carrier having an array of openings. The second carrier may be or include a material that inhibits the transport of the particle beam. The second carrier may be mounted for movement within a beam field of the particle beam. The motor may also be configured to move the second carrier along a track based on the movement of the particle beam. The first carrier and the second carrier may be physically connected to each other. The first carrier and the second carrier may be configured to move independently relative to each other. For example, the motor may be a first motor, and the collimator may also include a second motor configured to move the second carrier. The second motor may be configured to move the second carrier based on the movement of the particle beam.

[0018] An exemplary system includes a particle accelerator that generates a particle beam to treat a patient and a carrier having an opening. The carrier may be or include a material that inhibits the delivery of the particle beam. The carrier may be located between the particle accelerator and the patient. The system may include a control system to control movement of the particle beam to a first portion of the opening so that at least a portion of the particle beam can reach the patient, to change the energy of the particle beam when the particle beam remains stationary in the first portion of the opening, and to control movement of the particle beam from the first portion of the opening to a second portion of the opening. The exemplary system may include one or more of the following features, alone or in combination.

[0019] The opening may be or include a slot extending along the carrier. The control system may be configured to change the energy of the particle beam when the particle beam remains stationary at the second portion of the opening, and control movement of the particle beam from the second portion of the opening to a plurality of additional portions of the opening, wherein the particle beam remains stationary for a period of time at each of the plurality of additional portions of the opening while the energy of the particle beam is changed at each portion of the opening.

[0020] The control system can be configured to change the energy of the particle beam so that the particle beam treats a columnar portion of a target in a patient's body through the first portion of the opening before the particle beam moves from the first portion of the opening to the second portion of the opening. When the particle beam is in the first portion of the opening, the particle beam can deliver a radiation dose of more than 1 Gray per second to the target with a duration of less than 5 seconds. When the particle beam is in the first portion of the opening, the particle beam can deliver a radiation dose of 20 Gray per second to 100 Gray per second to the target with a duration of 10 milliseconds to 5 seconds. When the particle beam is in the first portion of the opening, the particle beam can deliver a radiation dose of 40 Gray per second to 120 Gray per second to the target with a duration of less than 5 seconds. When the particle beam is in the first portion of the opening, the particle beam can deliver a radiation dose to the target at an ultra-high dose rate.

[0021] The system may include a range adjuster between the particle accelerator and the patient. The range adjuster may include a structure configured to move into and out of the particle beam path so as to change the energy of the particle beam. The control system may be configured to control the movement of the structure into or out of the particle beam path to change the energy of the particle beam. The structure may be or include a plate for changing the energy of the particle beam when the particle beam passes through one or more plates. The one or more plates or structures may include boron carbide.

[0022] The particle accelerator may include a superconducting magnet including conductive coils. The control system may be configured to vary the current through the conductive coils to vary the energy of the particle beam.

[0023] The system may include a track on which the carrier is mounted for movement within a beam field of the particle beam. The motor may be configured to move the carrier along the track.

[0024] An example system includes a particle accelerator to provide a particle beam to treat a patient located in a treatment room. The system includes a range adjuster, which includes a plurality of structures. Each structure in the plurality of structures is used to change the energy of the particle beam when the particle beam passes through the structure. Each structure includes boron carbide. The system also includes an actuator, each actuator is used to control the movement of a corresponding one of the plurality of structures into or out of the particle beam path. The range adjuster is located in the treatment room. The system can include one or more of the following features alone or in combination.

[0025] Each structure may be a plate. Each structure may be a polyhedron. Each structure may be pure boron carbide. One or more of the plurality of structures may include a composite material consisting of boron carbide and graphite.

[0026] The range adjuster can be positioned so that the beam line of the particle beam is no more than 3 meters away from the patient. The range adjuster can be positioned so that the beam line of the particle beam is no more than 2 meters away from the patient. The range adjuster can be positioned so that the beam line of the particle beam is no more than 1 meter away from the patient. The system can include a scanning magnet to move the particle beam relative to the patient. The range adjuster can be located between the scanning magnet and the patient.

[0027] The particle beam can be applied to the patient at an ultra-high dose rate. The particle beam can be applied to the patient at a dose rate of more than 1 Gray per second for a duration of less than 5 seconds. The particle beam can be applied to the patient at a dose rate of 20 Gray per second to 100 Gray per second for a duration of 10 milliseconds to 5 seconds. The particle beam can be applied to the patient at a dose rate of 40 Gray per second to 120 Gray per second for a duration of less than 5 seconds.

[0028] The range adjuster may be structured to be controllable to move the particle beam in or out while the particle beam remains stationary in order to treat a column of tissue in a patient using an ultra-high dose rate. The actuator may be a linear motor or any other suitable type of motor.

[0029] An exemplary system includes a particle accelerator to provide a particle beam to treat a patient located in a treatment room. The system includes a range adjuster, which includes a plurality of structures. Each structure in the plurality of structures is used to change the energy of the particle beam when the particle beam passes through the structure. Each structure includes boron carbide. The system also includes an actuator, each actuator is used to control the movement of a corresponding one of the plurality of structures into or out of the particle beam path. The range adjuster is no more than 4 meters away from the patient along the beam line of the particle beam. The system can include one or more of the following features alone or in combination.

[0030] The structures may be controllable to move in or out of the particle beam while the particle beam remains stationary, thereby treating a column of tissue in a patient using an ultra-high dose rate. The range adjuster may be positioned no closer than 3 meters from the patient along the beam line of the particle beam. The range adjuster may be positioned no closer than 2 meters from the patient along the beam line of the particle beam. The range adjuster may be positioned no closer than 1 meter from the patient along the beam line of the particle beam.

[0031] The particle beam can be applied to the patient at an ultra-high dose rate. The particle beam can be applied to the patient at a dose rate of more than 1 Gray per second for a duration of less than 5 seconds. The particle beam can be applied to the patient at a dose rate of 20 Gray per second to 100 Gray per second for a duration of 10 milliseconds to 5 seconds. The particle beam can be applied to the patient at a dose rate of 40 Gray per second to 120 Gray per second for a duration of less than 5 seconds.

[0032] The range adjuster structure can be controllable to move in or out of the particle beam while the particle beam remains stationary so as to treat the column of tissue in the patient using an ultra-high dose rate. The actuator can be a linear motor or other type of motor. One or more of the plurality of structures can include a composite material composed of boron carbide and graphite.

[0033] An example system includes: a particle accelerator for providing a particle beam to treat a patient located in a treatment room; a scanning magnet for moving the particle beam relative to the patient; and a range adjuster. The range adjuster includes a plurality of structures. Each structure in the plurality of structures is used to change the energy of the particle beam when the particle beam passes through the structure. Each structure includes boron carbide. The system also includes an actuator, each actuator is used to control the movement of a corresponding one of the plurality of structures into or out of the particle beam path. The range adjuster is located between the scanning magnet and the patient. The system may include one or more of the following features, alone or in combination.

[0034] The range adjuster can be positioned no more than 1 meter from the patient along the beam line of the particle beam. The particle beam can be applied to the patient at an ultra-high dose rate. The particle beam can be applied to the patient at a dose rate in excess of 1 Gray per second for a duration of less than 5 seconds. The particle beam can be applied to the patient at a dose rate of 20 Gray per second to 100 Gray per second for a duration of 10 milliseconds to 5 seconds. The particle beam can be applied to the patient at a dose rate of 40 Gray per second to 120 Gray per second for a duration of less than 5 seconds. The range adjuster can be controllable in structure to move in or out of the particle beam while the particle beam remains stationary, thereby treating a column of tissue in the patient at an ultra-high radiation dose rate.

[0035] The system may include an external gantry on which the particle accelerator is mounted. The external gantry may be controllable to move the particle accelerator at least partially around the patient. The system may include an internal gantry that is controllable to move in unison with the external gantry. The internal gantry may include a nozzle that may extend toward the patient and may be retracted away from the patient. A range adjuster may be located in the nozzle. The range adjuster is located in a treatment room in which the particle beam is applied to the patient. The nozzle may be fully retracted into the internal gantry.

[0036] For a particle beam having an energy of 70 MeV or greater, the particle beam may have a beam spot size of less than 1.2 centimeters (cm) sigma. The particle beam may have a beam spot size of less than 1.2 centimeters (cm) sigma. The particle beam may have a beam spot size of less than 0.5 centimeters (cm) sigma.

[0037] There may be no structure between the range adjuster and the patient for affecting the particle beam. The system may include a configurable collimator between the range adjuster and the patient. The configurable collimator may be controllable to trim the particle beam with a resolution as small as a single beam spot. The actuator may include a linear motor. The actuator may include a rotary motor, each rotary motor driving a corresponding linear actuator to control the movement of the corresponding structure.

[0038] One or more of the plurality of structures in the range adjuster may include a composite material consisting of boron carbide and graphite. Each of the plurality of structures in the range adjuster may be pure boron carbide.

[0039] Two or more features described in this disclosure, including features described in this Summary, may be combined to form embodiments not specifically described herein.

[0040] Control of the various systems or portions thereof described herein may be implemented by a computer program product including instructions stored on one or more non-transitory machine-readable storage media and executable on one or more processing devices (e.g., microprocessor(s), application specific integrated circuits, programmed logic such as field programmable gate array(s), etc.). The systems or portions thereof described herein may be implemented as an apparatus, method, or electronic system, which may include one or more processing devices and computer memory to store executable instructions to implement control of the described functions.

[0041] The details of one or more implementations are set forth in the accompanying drawings and the description below. Other features, objects, and advantages will be apparent from the description and drawings, and from the claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 is a perspective view of an example radiation target that is treated by sequentially scanning a particle beam across a layer.

[0043] Figure 2 is a perspective view of an example radiation target that is treated by sequentially scanning a particle beam cylindrically across the target.

[0044] Figure 3 is a cross-sectional view of a portion of an exemplary particle accelerator that may be used in the particle therapy systems described herein.

[0045] Figure 4 is a side view of components of an exemplary scanning system that may be used in the particle therapy systems described herein.

[0046] Figure 5 is a perspective view of components of an exemplary scanning system that may be used in the particle therapy systems described herein.

[0047] Figure 6 is used for Figure 4 and 5 A front view of an exemplary magnet in a scanning system of the type shown.

[0048] Figure 7 is used for Figure 4 and 5 A perspective view of an exemplary magnet in a scanning system of the type shown.

[0049] Figure 8 is Figure 4 and 5 A perspective view of an exemplary range adjuster (eg, range modulator) for use in a scanning system of the type shown.

[0050] Fig. 9is a perspective view of the process for moving a range adjuster plate into and out of the particle beam path.

[0051] Fig.10 is a block diagram of an exemplary board of an exemplary linear motor and a range adjuster controlled thereby.

[0052] Fig.11 is a flow chart illustrating an example process for treating a radiation target by sequentially scanning a particle beam in a column across the target.

[0053] Fig.12 , 13 , 14 and 15 are perspective block diagrams showing a column for treating a radiation target by sequentially moving energy absorbing panels into the path of a stationary particle beam.

[0054] Fig.16 , 17 , 18 and 19 are perspective block diagrams showing a column for treating a radiation target by sequentially moving energy absorbing panels out of the path of a stationary particle beam.

[0055] Fig. 20 is a front view of an exemplary collimator including a two-dimensional array of holes.

[0056] Fig.21 is a front view of an exemplary collimator including a two-dimensional array of holes and control components for the collimator.

[0057] Fig. 22 is a perspective view of an exemplary collimator comprising a single linear array of holes.

[0058] Fig.23 yes Fig. 22 A perspective view of an exemplary collimator.

[0059] Fig.24 is a perspective view of an exemplary collimator including two linear arrays of apertures that are not independently controllable.

[0060] Fig.25 is a front view of an exemplary collimator including independently controllable carriers.

[0061] Fig.26 and 27 2 are front and perspective views, respectively, of an exemplary particle therapy system.

[0062] Fig.28 is a perspective view of an exemplary particle therapy system.

[0063] Fig.29 is a graph showing the change in beam spot size for different particle beam energies for different materials used in a range adjuster to change the particle beam energy.

[0064] Fig.30 is a front view of an exemplary collimator including a linear slot array.

[0065] Fig.31 is a front view of an exemplary collimator including a two-dimensional array of slots.

[0066] Fig.32 is a front view of an example slot, showing the collimation of a particle beam performed through the slot.

[0067] Fig.33 is a front view of an exemplary collimator including a linear array of slots, showing movement of a particle beam along a portion of the slots.

[0068] Fig.34 is a diagram showing an exemplary extended Bragg peak (SOBP) and a column as part of an exemplary irradiation target.

[0069] Figures 35 to 44 is a perspective block diagram illustrating an example process for irradiating a targeted column via microvolume therapy.

[0070] Fig.45A and 45B is a graph showing the results of a Monte Carlo simulation calculating the radiation dose delivered to a treatment volume and the time required for each voxel in the dose calculation to reach the final dose.

[0071] Fig.46 is a perspective view of an exemplary configurable collimator blade that may be used with the exemplary configurable collimators described herein.

[0072] Fig.47 is a top view of configurable collimator leaves positioned relative to a treatment area of ​​a radiation target.

[0073] Fig.48 is a perspective view of an exemplary configurable collimator.

[0074] Fig.49 is a front view of an exemplary configurable collimator.

[0075] Fig.50 is a perspective view of an exemplary configurable collimator having its components depicted in perspective to illustrate its interior.

[0076] Fig.51 is a perspective view of an exemplary configurable collimator positioned relative to a patient during particle therapy treatment.

[0077] The same reference symbols in different drawings denote the same elements. DETAILED DESCRIPTION

[0078] Described herein are exemplary embodiments of particle therapy systems including collimators. Particle therapy systems are used to treat a radiation target ("target"), such as a tumor, in a patient's body using a particle beam (such as a proton beam or an ion beam). Some systems treat a cross-section of the target layer by layer. For example, the energy of the particle beam can be controlled to deliver a radiation dose ("dose") to one layer, and then the particle beam can be moved across all or part of that layer. Thereafter, the energy of the particle beam can be changed to deliver the dose to another layer. The particle beam can be moved through all or part of other layers, and so on, until the entire target is treated. For example, Figure 1 The entire layer 10 of the target 11 is shown to be treated with a particle beam 12, the energy of which is sufficient to deliver a dose to the layer 10 by moving the particle beam through the layer 10 in the direction of arrow 15. A different layer 16 of the target 11 is then treated in the same manner using a particle beam having a different energy sufficient to deliver a dose to the layer 16, and so on. The average treatment of the entire treatment volume is usually carried out at a relatively small dose rate, for example 0.1 gray per second. The particle beam usually penetrates healthy tissue before reaching the target. During the treatment, any position in this healthy tissue can be treated several times. The dose at such a position is received on a time scale of the order of minutes.

[0079] In contrast, some particle therapy systems can use ultra-high (FLASH) dose rate radiation to treat a three-dimensional cylindrical area of ​​a target. These systems use pencil particle beam scanning to adjust the ultra-high dose rate delivered to the target. In some examples, pencil particle beam scanning includes a series of small particle beams that deliver particle radiation, each of which can have a unique direction, energy, and charge. By combining the doses from these individual particle beams, a three-dimensional target treatment volume can be treated with radiation. In addition, instead of arranging treatment for multiple layers at a constant energy, the system organizes the treatment into a column defined by the direction of a stationary particle beam. The direction of the particle beam can be toward the surface of the target.

[0080] In some embodiments, the whole or part of the column is treated before the particle beam passes through the radiation target along another path. In some embodiments, the path through the target passes through all or part of the target. In one example, the particle beam can be guided along the path through the target and does not deviate from the path. When guided along the path, the energy of the particle beam is changed. The particle beam does not move with the change of its energy, so the particle beam treats all or part of the inside of the target along the length of the particle beam and the width of the beam spot. Therefore, the treatment is carried out along the longitudinal depth of the particle beam. For example, a part of the target being treated can extend downward from the beam spot at the surface of the target through all or part of the inside of the target. The result is that the particle beam uses ultra-high dose rate radiation to treat the three-dimensional columnar portion of the target. In some examples, ultra-high dose rate radiation includes, for example, more than 1 Gray per second in a duration of less than 500 milliseconds (ms), more than 1 Gray per second in a duration between 10ms and 5 seconds, or more than 1 Gray per second in a duration of less than 5s. Other examples are provided herein.

[0081] In some embodiments, after treating the cylindrical portion of the target as described in the above paragraph, the particle beam is directed along a new and different path through the target. Figure 2 2, a column 20 of a target 21 is treated by changing the energy of a particle beam 22 traveling in the direction of arrow 28. The particle beam is then directed through the target 21 along a new path 24, where it travels in the direction of arrow 29. A column 25 is then treated along the new path by changing the energy of the particle beam while the particle beam is stationary. As previously described, the column is within the longitudinal extent of the particle beam. In some embodiments, when treating a column of a target, the particle beam is directed only once along each path through the target. As a result, healthy tissue above or below the target 21 is exposed to the ultra-high dose rate of radiation once, rather than once. Figure 1 The target is treated layer by layer in a single shot with multiple low doses of radiation.

[0082] In other words, in some embodiments, the particle beam is directed along a new path, and upstream tissue along that path is no longer visited. In this way, each location within the target can be treated at a dose rate that is comparable to the dose rate of a single pencil beam modulated according to the layer switching time. The average dose rate throughout the treatment may be comparable to layer-by-layer radiation therapy, but the local dose rate at any one beam spot is at an ultra-high dose rate. In some cases, damage to healthy tissue may be reduced when radiating at ultra-high dose rates. For example, when a radiation dose of 10 to 20 Gray is delivered in pulses of less than 500 milliseconds - achieving an effective dose rate of 20 to 100 Gray per second - healthy tissue may be less damaged than when irradiated with the same dose over a longer time scale, while the delivered radiation can treat the tumor with the same level of effectiveness.

[0083] In some embodiments, the operating speed of the hardware used to generate and adjust the particle beam may affect the ability to deliver radiation at an ultra-high dose rate. For example, in order to achieve an ultra-high dose rate, the energy of the particle beam can be changed at a dose rate that exceeds the energy change used for layer-by-layer scanning. For example, by switching the particle beam energy within a duration of 50 milliseconds, an ultra-high dose rate applied to the target column can be achieved. This can be achieved by, for example, controlling the movement of the particle beam and the movement of an energy absorption plate containing boron carbide or other structures containing boron carbide into and out of the particle beam path. For example, a 5-centimeter (cm) deep column that may require 5-layer switching may require 250 milliseconds of downtime, during which the particle beam is not delivered, allowing 250 milliseconds of particle beam delivery, during which a dose of 10 to 20 Gray can be delivered. Faster movement of the energy absorption plate and / or additional coordination of the particle beam movement can further reduce the layer switching time, allowing even more time to deliver the required therapeutic dose, while still meeting the requirements of the local ultra-high dose rate.

[0084] Also described herein are exemplary embodiments of collimators for particle therapy systems. Collimation is used to align adjacent beam spots (e.g., Figure 1 ) or adjacent columns (e.g. Figure 2 ) are isolated from each other can enable the system to achieve FLASFI dose rate or non-FLASFI dose rate in a localized area (e.g., a beam spot or column) without radiation leakage into adjacent areas, or only a minimum acceptable amount of radiation leakage into adjacent areas.

[0085] In some embodiments, the collimator can include a carrier having one or more openings, such as one or more holes or slots, through which the particle beam passes to reach a target in the patient. The carrier can be a flat plate, a polyhedron, or a curved three-dimensional (3D) structure made of a material that blocks the passage of the particle beam. For example, the carrier can be made of a metal, such as nickel, brass, or tungsten, with a thickness sufficient to prevent radiation of a given energy from passing through. In some embodiments, the size and shape of one or more openings are fixed; for example, the size and shape are non-changeable or non-configurable. For example, the shape and contents of the collimator can be static. The particle beam can move within or between the openings. Each opening trims the particle beam by allowing a portion of the particle beam to pass through the opening to reach a target in the patient's body while preventing different portions of the particle beam from reaching the patient. Trimming can collimate the particle beam. For example, as a result of trimming, the amount of dispersion along the particle beam path can be reduced.

[0086] A control system, such as a computing system, can be configured to control the movement of the particle beam to a first hole (an example of an opening) of the collimator so that at least a portion of the particle beam can reach the patient, change the energy of the particle beam while the particle beam remains stationary at the first hole, and control the movement of the particle beam from the first hole to the second hole. The control system can also be configured to change the energy of the particle beam while the particle beam remains stationary at the second hole, and control the movement of the particle beam from the second hole to a plurality of additional holes. At each of the plurality of additional holes, the particle beam is controlled to remain stationary for a period of time when the energy of the particle beam changes. As a result, at each hole, the particle beam is trimmed, and due to the energy change, the particle beam treats a three-dimensional column in the target.

[0087] The speed at which a collimator used in a particle therapy system operates may affect the system's ability to deliver radiation at ultra-high dose rates. The exemplary collimators described herein may have limited or no configurability, thereby reducing or eliminating the amount of time required to configure the collimator during treatment. Thus, the collimator may be particularly useful when delivering radiation at ultra-high (FLASH) dose rates. However, the collimator may be used when delivering radiation at dose rates that are not ultra-high. In some embodiments, a configurable collimator may be used.

[0088] Described below is an exemplary embodiment of a particle therapy system configured to deliver radiation at an ultra-high dose rate through a three-dimensional column of a target. In an exemplary embodiment, the particle therapy system is a proton therapy system. As described herein, the exemplary proton therapy system scans a proton beam through a radiation target in three dimensions to destroy malignant tissue. Figure 3A cross section of a component 310 of an exemplary superconducting synchrocyclotron that can be used to provide a particle (e.g., proton) beam in a proton therapy system is shown. In this example, component 310 includes a superconducting magnet 311. The superconducting magnet includes superconducting coils 312 and 313. The superconducting coils are formed by a plurality of integrated conductors, each of which includes a superconducting strand, such as four or six strands, wound around a central strand, which itself can be superconducting or non-superconducting. Each superconducting coil 312, 313 is used to conduct an electric current that can generate a magnetic field (B). Magnetic yokes 314, 315 or smaller pole pieces form a magnetic field in a cavity 316 where particles are accelerated. In one example, a cryostat (not shown) conducts and cools each coil to a superconducting temperature, such as about 4 Kelvin (K), using liquid helium (He).

[0089] In some embodiments, the particle accelerator includes a particle source 317, such as a Penning Ion Gauge-PIG source, to provide an ionized plasma column to the cavity 316. Hydrogen or a combination of hydrogen and an inert gas is ionized to produce a plasma column. A voltage source provides a varying radio frequency (RF) voltage to the cavity 316 to accelerate particles from the plasma column in the cavity. As described above, in one example, the particle accelerator is a synchrocyclotron. Therefore, when accelerating particles in the cavity, the RF voltage sweeps across a certain frequency range to account for relativistic effects of the particles, such as increasing the mass of the particles. The RF voltage drives a dee plate contained in the cavity, the frequency of which is swept downward during the acceleration cycle to account for the increase in the relativistic mass of the protons and the decrease in the magnetic field. The pseudo-D-shaped plate serves as a ground reference for the D-shaped plate. The magnetic field generated by the current flowing through the superconducting coil, together with the scanned RF voltage, accelerates the particles in the plasma column along the track in the cavity, and increases the energy as the number of turns increases.

[0090] The magnetic field in the cavity is shaped to cause the particles to orbit within the cavity. An exemplary synchrocyclotron uses a magnetic field whose rotation angle is uniform and whose strength decreases with increasing radius. In some embodiments, the maximum magnetic field generated by the superconducting (main) coil can be in the range of 4 Tesla (T) to 20 T at the center of the cavity, with the range decreasing with increasing radius.For example, a superconducting coil can be used to generate a magnetic field of one or more of the following magnitudes: 4.0 T, 4.1 T, 4.2 T, 4.3 T, 4.4 T, 4.5 T, 4.6 T, 4.7 T, 4.8 T, 4.9 T, 5.0 T, 5.1 T, 5.2 T, 5.3 T, 5.4 T, 5.5 T, 5.6 T, 5.7 T, 5.8 T, 5.9 T, 6.0 T, 6.1 T, 6.2 T, 6.3 T, 6.4 T, 6.5 T, 6.6 T, 6.7 T, 6.8 T, 6.9 T, 7.0 T, 7.1 T, 7.2 T, 7.3 T, 7.4 T, 7.5 T, 7.6 T, 7.7 T, 7.8 T, 7.9 T, 8.0 T, 8.1 T, 8.2 T, 8.3 T, 8.4 T, 8.5 T, 8.6 T, 8.7 T, 8.8 T, 8.9 T, 9.0 T, 9.1 T, 9.2 T, 9.3 T, 9.4 T, 9.5 T, 9.6 T, 9.7 T, 9.8 T, 9.9 T, 10.0 T, 10.1 T, 10.2 T, 10.3 T, 10.4 T, 10.5 T, 10.6 T, 10.7 T, 10.8 T, 10.9 T, 11.0 T, 11.1 T, 11.2 T, 11.3 T, 11.4 T, 11.5 T, 11.6 T, 11.7 T, 11.8 T, 11.9 T, 12.0 T, 12.1 T, 12.2 T, 12.3 T, 12.4 T, 12.5 T, 12.6 T, 12.7 T, 12.8 T, 12.9 T, 13.0 T, 13.1 T, 13.2 T, 13.3 T, 13.4 T, 13.5 T, 13.6 T, 13.7 T, 13.8 T, 13.9 T, 14.0 T, 14.1 T, 14.2 T, 14.3 T, 14.4 T, 14.5 T, 14.6 T, 14.7 T, 14.8 T, 14.9 T, 15.0 T, 15.1 T, 15.2 T, 15.3 T, 15.4 T, 15.5 T, 15.6 T, 15.7 T, 15.8 T, 15.9 T, 16.0 T, 16.1 T, 16.2 T, 16.3 T, 16.4 T, 16.5 T, 16.6 T, 16.7 T, 16.8 T, 16.9 T, 17.0 T, 17.1 T, 17.2 T, 17.3 T, 17.4 T, 17.5 T, 17.6 T, 17.7 T, 17.8 T, 17.9 T, 18.0 T, 18.1 T, 18.2 T, 18.3 T, 18.4 T, 18.5 T, 18.6 T, 18.7 T, 18.8 T, 18.9 T, 19.0 T, 19.1 T, 19.2 T, 19.3 T, 19.4 T, 19.5 T, 19.6 T, 19.7 T, 19.8 T, 19.9 T, 20.0 T, 20.1 T, 20.2 T, 20.3 T, 20.4 T, 20.5 T, 20.6 T, 20.7 T, 20.8 T, 20.9 T or greater.Furthermore, the superconducting coils may be used to generate magnetic fields outside the range of 4T to 20T or within the range of 4T to 20T but not specifically listed herein.

[0091] In some embodiments, for example Figure 3 In the illustrated embodiment, relatively large ferromagnetic yokes 314, 315 are used as a return mechanism for stray magnetic fields generated by the superconducting coils. In some systems, a magnetic shield (not shown) surrounds the yokes. The return yokes and shields together serve to reduce stray magnetic fields, thereby reducing the possibility that stray magnetic fields will adversely affect the operation of the particle accelerator.

[0092] In some embodiments, the return yoke and shield may be replaced or enhanced by an active return system. An exemplary active return system includes one or more active return coils that conduct current in a direction opposite to the current through the main superconducting coils. In some exemplary embodiments, there is one active return coil per superconducting main coil, such as two active return coils - one for each main superconducting coil. Each active return coil may also be a superconducting coil that is concentrically wrapped around the outside of the corresponding main superconducting coil.

[0093] By using an active return system, the relatively large ferromagnetic yokes 314, 315 can be replaced with smaller and lighter pole pieces. Thus, the size and weight of the synchrocyclotron can be further reduced without sacrificing performance. An example of an active return system that can be used is described in U.S. Patent No. 8,791,656, entitled "ActiveReturn System," the contents of which are incorporated herein by reference.

[0094] At or near the output of the extraction channel of the particle accelerator, there may be one or more beam shaping elements including a scanning system. Components of the scanning system may be mounted or otherwise attached to the nozzle for positioning relatively close to the patient during treatment.

[0095] refer to Figure 4 In an exemplary embodiment, in a synchrocyclotron 421 (which may have Figure 3 At the output of the extraction channel 420 (configuration of FIG. 4 ) is an exemplary scanning component 422 that can be used to move the particle beam in three dimensions past the irradiation target. Figure 5 It also shows Figure 4 These include, but are not limited to, one or more scanning magnets 424, ion chamber 425, energy degrader 426, and collimator 428. Figure 4Other components that may be downstream of the particle beam in the extraction channel are not shown in 5 and may include, for example, one or more scattering devices for changing the beam spot size. Example scattering devices include plates or range modulators that disperse the particle beam as it passes through the scattering device.

[0096] In an exemplary operation, the scanning magnet 424 is controllable in two dimensions (e.g., Cartesian XY dimensions) to position the particle beam in the two dimensions and to move the particle beam through at least a portion of the radiation target. The ion chamber 425 detects the dose of the particle beam and feeds this information back to the control system to adjust the particle beam movement. The range adjuster 426 is controllable to move structures into and out of the path of the particle beam, thereby changing the energy of the particle beam and thus changing the depth at which the dose of the particle beam is deposited in the radiation target. Examples of such structures include, but are not limited to: energy absorbing plates; polyhedrons, such as wedges, tetrahedrons, or curved polyhedrons; and curved three-dimensional shapes, such as cylinders, spheres, or cones. In this way, the range adjuster can cause the particle beam to deposit a certain dose of radiation inside the radiation target to treat the column of the target. In this regard, when protons pass through tissue, the protons ionize the atoms of the tissue and deposit a dose along their path. The Bragg peak is a distinct peak on the Bragg curve, which plots the energy loss of ionizing radiation during its passage through tissue. The Bragg peak represents the depth within tissue where most protons are deposited. For protons, the Bragg peak occurs just before the particles come to rest. Therefore, the energy of a particle beam can be varied to change the position of its Bragg peak, so that most of the dose of protons will be deposited deep within tissue.

[0097] Figure 6 and 7 A view of an example scanning magnet 424 is shown. In this example, the scanning magnet 424 includes two coils 441 and two coils 442, which control the movement of the particle beam in the X dimension, and the coils 442 control the movement of the particle beam in the Y dimension. In some embodiments, the control is achieved by changing the current through one or two groups of coils to change the magnetic field generated thereby. By appropriately changing the magnetic field, the particle beam can move in the X and / or Y direction on the radiation target. The range adjuster described above can move the particle beam through the target in the Z dimension, thereby achieving three-dimensional scanning.

[0098] Return to reference Figure 4, the current sensor 427 can be connected to the scanning magnet 424, or otherwise associated with the scanning magnet 424. For example, the current sensor can communicate with the scanning magnet, but is not connected to the scanning magnet. In some embodiments, the current sensor samples the current applied to the magnet 424, which may include the current to the coil for controlling the particle beam scanning in the X dimension and / or the current to the coil for controlling the particle beam scanning in the Y dimension. The current sensor can sample the current passing through the magnet at a time corresponding to the pulse appearing in the particle beam or at a dose rate exceeding the dose rate of the pulse appearing in the particle beam. The sample identifying the magnet current is related to the detection of the pulse by the ion chamber described below. For example, the time of detecting the pulse using the ion chamber can be temporally associated with the sample from the current sensor, thereby identifying the current in the magnetic coil when the pulse is detected. Therefore, using the magnet current, the position of each pulse and the radiation dose (i.e., particle dose) delivered in the radiation target can be determined. The position of the dose delivered in the target can also be determined based on the configuration of the range adjuster, for example, based on the number of plates in the particle beam path.

[0099] During operation, the magnitude of the magnet current and the amount of the dose (e.g., intensity) can be stored for each location where the dose is delivered. A control system (which can be on the accelerator or remote from the accelerator and can include a memory and one or more processing devices) can associate the magnet current with coordinates within the radiation target, and these coordinates can be stored together with the amount of the dose. For example, a location can be identified by the number of layers in the depth direction and a Cartesian XY coordinate or a Cartesian XYZ coordinate, where the layers in the depth direction correspond to the Z coordinate. In some embodiments, the magnitude of the magnet current and the coordinate position can be stored together with the dose at each location. This information can be stored in a memory on the accelerator or in a memory remote from the accelerator. This information can be used to track the treatment of the target and keep a record of the treatment.

[0100] The ion chamber 425 detects the dose, such as one or more individual doses, applied by the particle beam to a location within the radiation target by detecting the number of ion pairs generated in the gas caused by the incident radiation. The number of ion pairs corresponds to the dose provided by the particle beam. This information is fed back to the control system and stored in a memory together with the time at which the dose was provided. As described above, this information can be associated with and stored in association with the location at which the dose was provided and / or the magnitude of the magnet current at that time.

[0101] The collimator 428 may be positioned downstream of the scanning magnet and downstream of the range adjuster. Figure 4 and 5As shown. The collimator can trim the particle beam spot by spot as the particle beam moves from one path to another through the target. The collimator can also trim the particle beam when the particle beam is stationary on the target, and when the energy of the stationary particle beam changes to affect different parts of the interior of the target. For example, when the particle beam enters the interior of the target, the particle beam can spread along its diameter. The collimator can be configured (e.g., constructed) to trim the particle beam to account for this spread. For example, the collimator can be configured to reduce the dispersion of the particle beam reaching and passing through the target, thereby maintaining a more constant beam spot size.

[0102] As described below, in some examples, the collimator may include one or more openings through which the particle beam may be directed. For example, the collimator may include a plurality of holes, such as circular holes, arranged in a one-dimensional array or a multi-dimensional array. In some examples, the size and shape of the holes are immutable or non-configurable. The particle beam may be moved into the holes in a specific order to treat a target portion in the patient's body. Each hole may trim and collimate the particle beam. The holes may be positioned close enough to each other to limit the amount of overlap of the individual beam spots of the particle beam. This is done to limit the ultra-high dose rate radiation of healthy tissues above and below the target. In some embodiments, holes may be formed through a carrier such as a substrate that suppresses or blocks radiation. The carrier itself may move within the beam field based on, for example, the movement of the particle beam. For example, a carrier with a linear array of holes may be configured to track the movement of the particle beam through the beam field. However, because the holes themselves do not need to be configured, the amount of time required for the carrier to move does not hinder the delivery of radiation at an ultra-high dose rate.

[0103] In some embodiments, the collimator may include one or more slots passing through the carrier, instead of holes, or including one or more slots in addition to holes. For example, the collimator may include a single linear slot having a lateral dimension sufficient to trim the particle beam, and a longitudinal dimension that extends across at least a portion of the radiation target and can accommodate multiple beam spots. In some embodiments, the collimator may include a plurality of linear slots arranged in an array. In some examples, the size and shape of the slots are immutable or non-configurable. The particle beam can be moved to a portion of each slot, which performs collimation in the lateral dimension (and in the longitudinal dimension of the beam spot at the slot end). In some embodiments, slots may be formed through a carrier such as a substrate that suppresses or blocks radiation. The carrier itself may move within the beam field based on, for example, the movement of the particle beam. For example, a carrier with a single slot may be configured to track the movement of the particle beam through the beam field. However, because the slot itself does not need to be configured, the amount of time required for the carrier to move does not hinder the delivery of radiation at an ultra-high dose rate.

[0104] Figure 8An exemplary range modulator 460 is shown, which is an exemplary embodiment of the range regulator 426. In some embodiments, the range modulator 460 can be located downstream of the particle beam of the scanning magnet between the collimator and the patient. In some embodiments, such as Figure 8 As shown, the range modulator includes a series of plates 461. These plates can be made of one or more of the following example materials: polycarbonate (such as LEXAN TM ), carbon, beryllium, boron carbide, a composite material composed of boron carbide and graphite, or a low atomic number material. However, other materials may be used instead of or in addition to these example materials. In other embodiments of the range adjuster, a polyhedron, such as a wedge, a tetrahedron, or a curved polyhedron, or a curved three-dimensional structure, such as a cylinder, a sphere, or a cone, may be made of one or more of the following example materials: polycarbonate, such as LEXAN TM , carbon, beryllium, boron carbide, composites consisting of boron carbide and graphite, or materials with low atomic number.

[0105] In some embodiments, the structures of the range modulator containing boron carbide may include only boron carbide; that is, these structures may be pure boron carbide. In some embodiments, the structures containing boron carbide may include boron carbide combined with another material, such as graphite, polycarbonate, carbon, or beryllium. In some embodiments, each structure in the range modulator (e.g., a plate, a polyhedron, or a curved three-dimensional structure) may include all or part of boron carbide. In some embodiments, different structures in the range modulator (e.g., a plate, a polyhedron, or a curved three-dimensional structure) may include different materials. For example, one or more plates in the range modulator may be made of pure boron carbide, and one or more other plates of the same range modulator may be made of or include one or more of polycarbonate, carbon, and / or beryllium. Other materials may also be used. For example, one or more plates in the range modulator or portions thereof may be made of a composite material comprising boron carbide and graphite.

[0106] One or more plates can be moved into or out of the particle beam path to change the energy of the particle beam and thereby change the depth at which the majority of the particle beam dose is deposited within the irradiation target. The plates are physically moved into and out of the particle beam path. For example, Fig. 9 As shown, plate 470 moves between a position in the path of particle beam 473 and a position outside the path of the particle beam in the direction of arrow 472. These plates are computer controlled. Typically, the number of plates moved into the path of the particle beam corresponds to the depth at which the scanning of the irradiation target occurs. Therefore, by appropriately controlling one or more plates, the dose of the particle beam can be directed to the interior of the target.

[0107] In some embodiments, each of the plates of the range modulator 460 is connected to and driven by a corresponding motor 464. In general, a motor includes a device that converts some form of energy into motion. The motor can be rotary or linear, and can be electric, hydraulic or pneumatic. For example, each motor can be a motor that drives a lead screw to extend the plate into the beam field or retract the plate from the beam field, including making the movement of the plate track or follow the movement of the particle beam in the beam field. For example, each motor can be a rotary motor that drives a corresponding linear actuator to control the movement of the corresponding structure. In some embodiments, each plate of the range modulator 460 is connected to and driven by a corresponding actuator. In some examples, the actuator includes a mechanical or electromechanical device that provides controlled motion, and can be electrically operated by a motor, hydraulic, pneumatic, mechanical or thermal. In some examples, the actuator includes any type of motor operated by an energy source (e.g., electric current, hydraulic fluid pressure or pneumatic pressure) and converting the energy into motion.

[0108] In some embodiments, a range adjuster comprising a boron carbide structure (or a structure composed of other materials) can be located in a treatment room where the particle beam is applied to a patient. For example, the range adjuster can be located between the scanning magnet and the patient. In one example, the range adjuster can be located in a nozzle on an internal gantry of the system, an example of which is shown in FIG. Fig.26 , 27 and 28 for description.

[0109] The range adjuster can be located close to the patient to limit the amount of particle beam that is scattered or dispersed after passing through one or more plates or other structures. In some embodiments, the range adjuster can be located no more than 4 meters away from the patient along the beam line of the particle beam. In some embodiments, the range adjuster can be located no more than 3 meters away from the patient along the beam line of the particle beam. In some embodiments, the range adjuster can be located no more than 2 meters away from the patient along the beam line of the particle beam. In some embodiments, the range adjuster can be located no more than 1 meter away from the patient along the beam line of the particle beam. In some embodiments, the range adjuster can be located no more than half a meter away from the patient along the beam line of the particle beam. In some embodiments, the range adjuster can be located in a nozzle located no more than 4 meters away from the patient along the beam line of the particle beam. In some embodiments, the range adjuster can be located in a nozzle located no more than 3 meters away from the patient along the beam line of the particle beam. In some embodiments, the range adjuster can be located in a nozzle located no more than 2 meters away from the patient along the beam line of the particle beam. In some embodiments, the range adjuster can be positioned within the nozzle no more than 1 meter from the patient along the beamline of the particle beam. In some embodiments, the range adjuster can be positioned within the nozzle no more than half a meter from the patient along the beamline of the particle beam.

[0110] In general, boron carbide may be cheaper and safer than some other materials that can be used to reduce the energy of particle beams, such as beryllium. In general, boron carbide has a relatively low atomic weight and high density, and can be compared with some other materials that can be used to reduce the energy of particle beams, such as carbon (e.g., graphite) and polycarbonate in scattering characteristics. Reducing particle beam scattering results in a reduction in beam spot size, that is, a reduction in the cross-sectional size of the particle beam. The reduced beam spot size provides improved conformality and higher local dose rate in a pencil particle beam scanning system. In other words, reducing the beam spot size reduces the area where the dose is deposited. As a result, the concentration of protons deposited in a single beam spot increases, thereby increasing the dose rate within a single beam spot area. When scanning is performed using an ultra-high (or "FLASH") dose rate, it is desirable to increase the dose rate within a single beam spot area because it helps to deposit an ultra-high dose of protons within a specified time. This article describes an example during the administration of an ultra-high dose.

[0111] Different materials used in range modifiers to change the energy of particle beams, Fig.29 A graph showing the variation of the beam spot size for different particle beam energies is shown. In this example, the LEXAN TM , carbon (such as graphite), boron carbide and beryllium. Fig.29 Graph showing, for example, a boron carbide range adjuster structure producing a particle beam with a spot size of less than 1.2 centimeters (cm) sigma at an energy of 70 MeV (million electron volts). In this example, the spot size is measured at the output of the range adjuster structure. The farther the particle beam travels in the air, the more the beam spot will scatter, which will cause the spot size to increase. However, placing the range adjuster close enough to the patient will limit the scattering. Additionally, in some but not all cases, a collimator can be placed between the range adjuster and the patient to collimate the particle beam, thereby limiting the effects caused by scattering.

[0112] In addition to the above advantages, the size of the range adjuster based on boron carbide can be reduced relative to, for example, a range adjuster using polycarbonate. That is, the range adjuster based on boron carbide can achieve substantially the same effect as the range adjuster based on polycarbonate, but the range adjuster based on boron carbide can have a smaller form factor than the range adjuster based on polycarbonate. This is because the density of boron carbide is greater than the density of polycarbonate. In some examples, a range adjuster composed of pure boron carbide plates can be 30 centimeters (cm) to 40 cm thick along the beam line. These plates can have the same or different thicknesses. The thickness of the plates and the thickness of the range adjuster itself will depend on various factors, such as the total amount of energy variation required and the number of layers to be treated, which can determine the number and thickness of each plate.

[0113] The reduced size of the range adjuster comprised of boron carbide makes the range adjuster less obtrusive in a treatment room. For example, a range adjuster comprised of all or some of the boron carbide structure can be housed within a nozzle on an internal gantry. The nozzle including the range adjuster can be fully retracted into the internal gantry, thereby removing the range adjuster from the view of a technician performing a treatment. In some embodiments, the internal gantry can be flush with a wall of the treatment room, in which case fully retracting the nozzle and range adjuster into the internal gantry results in the nozzle and range adjuster being fully retracted into the wall.

[0114] Fig.10 An exemplary embodiment of a range modulator, such as a boron carbide based range modulator, is shown that uses a linear motor to control the operation of the energy absorbing panels 101, 102, and 103. Otherwise, Fig.10 The range modulator can have Figure 8 range modulator configuration. Although Fig.10 Only three plates are shown in the example of FIG. 1 , but any suitable number of plates may be included, as indicated by ellipse 106 .

[0115] Taking board 102 as an example, an exemplary linear motor that controls the operation of board 102 includes a movable component and a fixed component consisting of two parts - in this example, magnets 110a and 110b. The two magnets are arranged side by side with their poles aligned. That is, as shown in the figure, the positive pole (+) of magnet 110a is aligned with the positive pole (+) of magnet 110b, and the negative pole (-) of magnet 110a is aligned with the negative pole (-) of magnet 110b. The movable component includes a coil carrier plate 109 between magnets 110a and 110b. The coil carrier plate 109 is physically connected to the energy absorbing plate 102 and controls the movement of the energy absorbing plate 102 in the direction of arrow 111, such as entering and leaving the path of the particle beam.

[0116] As explained, the coil carrier plate 109 includes one or more conductive traces or other conductive structures that transmit current to generate a magnetic field. The magnetic field is controlled by controlling the current flowing through the coil carrier plate so as to control the movement of the coil carrier plate, thereby controlling the movement of the energy absorption plate 102. That is, the current passing through the coil generates a magnetic field that interacts with the magnetic field generated by the magnets 110a and 110b. This interaction causes the coil carrier plate 109 and the energy absorption plate 102 to move in the direction of arrow 111, entering or leaving the particle beam path. For example, a larger magnetic field generated by the coil carrier plate 109 can cause the energy absorption plate to move into the particle beam path, while a smaller or opposite magnetic field generated by the coil carrier plate can cause the energy absorption plate to retract from the particle beam path.

[0117] In some embodiments, the conductive traces or other conductive structures on the coil carrier plate can include three windings embedded in aluminum. In some embodiments, the energy absorbing plate can be physically attached to the coil carrier plate and move with the coil carrier plate. In some embodiments, the number of windings and the materials used can be different from those described herein. In some embodiments, the coil carrier plate can be an integral part of the energy absorbing plate. For example, the energy absorbing plate itself can include conductive structures or traces.

[0118] like Fig.10 As shown, in some embodiments, the current through the coil carrier plate can be controlled by a signal received from a control system such as a computing system 114. The computing system may be susceptible to neutron radiation and therefore may be located in a remote room 116. In some embodiments, the remote room 116 may be shielded from the neutron radiation produced by the particle accelerator. In some embodiments, the remote room may be located far enough away from the treatment room 117 so as not to be affected by the neutron radiation from the particle accelerator. In some embodiments, the computing system may be located in the treatment room, but may be shielded from the neutron radiation emitted by the particle accelerator. In some embodiments, all computing functions are shielded from neutron radiation, and unshielded electronic devices can still operate in the presence of neutron radiation. An encoder is an example of such an electronic device.

[0119] In this regard, the encoder (not shown) may include one or more of a laser sensor, an optical sensor, or a diode sensor. The encoder detects the movement of the coil carrier plate, for example by detecting the position of a mark or other identifier on the coil carrier plate or on a structure connected to and moving with the coil carrier plate relative to the encoder. Information about where the coil carrier plate is is fed back to the computing system and is used by the computing system to confirm the position of the coil carrier plate during operation. The encoder can be located in any suitable location. In some embodiments, the encoder is located on a housing that includes the coil carrier plate. As the plate moves, the mark or other identifier that moves with the coil carrier plate moves past the encoder. The encoder then forwards this information to the computing system 114. The computing system 114 can use this information to control the operation of the range modulator, including positioning its energy absorbing plate.

[0120] The computing system 114, which may be comprised of one or more processing devices, may be programmed to control the proton therapy system, including components of the scanning system, to deliver ultra-high dose rate radiation therapy in a radiation target column by column. For example, the computing system may be controllable to output one or more control signals to control one or more linear motors to extend or retract one or more energy absorbing plates during a scan. For example, the computing system may be controllable to output one or more control signals to control one or more motors to extend or retract one or more energy absorbing plates during a scan. The computing system may include one or more processing devices, such as a microprocessor, a microcontroller, a field programmable gate array (FPGA), or an application specific circuit (ASIC).

[0121] refer to Fig.11 , the control system can be configured (e.g., programmed) to implement a treatment plan for a target (e.g., a tumor). The treatment plan can specify parameters, including a dose rate of the particle beam to be used, such as an ultra-high dose rate, a location to deliver the dose to the target, and an order of columns of targets to be treated. Initially, the control system can control a particle accelerator - in this example, a synchrocyclotron 310 - to produce (1101) a particle beam with specific parameters, including particle beam current and intensity. In some embodiments, the particle beam current of the particle beam is a current of 100 nanoamperes or less. In some embodiments, the particle beam current of the particle beam is a current of 50 nA or less. Beam current levels on the order of nanoamperes can reduce the risk of injury to the patient, can reduce the risk of damage to the accelerator or other electronic equipment in the treatment room, or can reduce the risk of both such injury and damage.

[0122] The intensity of the particle beam can also be controlled (1102) or modulated to control or vary the dose applied to the target at different particle beam energies. Thus, intensity modulated proton therapy (IMPT) can be implemented using the techniques described herein. In some embodiments, the same radiation target can be treated at a FLASH dose rate or a dose rate lower than the FLASH dose rate using particle beams having different or the same intensities from multiple different angles. For example, a radiation target can be treated at a FLASH or non-FLASH dose rate by delivering radiation through a column at different angles. In such an example, because the radiation is delivered at different angles, healthy tissue that is not being treated can be irradiated only once.

[0123] The particle beam intensity is based at least in part on the number of particles in the particle beam. For example, the beam intensity can be defined by the number of particles in the particle beam. The intensity of the particle beam can vary between different beam spots of the particle beam. In addition, the intensity of one beam spot of the particle beam can be independent of the intensity of one or more other beam spots of the particle beam, including horizontally adjacent beam spots or vertically adjacent beam spots. Therefore, in some examples, any beam spot in three-dimensional space can be treated to an arbitrary dose, regardless of the dose of one or more adjacent beam spots. The control system can use one or more techniques to control the particle beam intensity.

[0124] In an example technique, the intensity of a particle beam can be controlled by changing the duration of a particle pulse obtained from a plasma column. In more detail, an RF voltage is scanned from a starting (e.g., maximum) frequency (e.g., 135 megahertz (MHz)) to an ending (e.g., minimum) frequency (e.g., 90 MHz). During the RF scan, a particle source is activated for a period of time to produce a plasma column. For example, in some embodiments, a particle source is activated for a period of time at 132 MHz. During this period, particles are extracted from the plasma column by the electric field generated by the RF voltage. As the frequency of the RF voltage decreases, the particles accelerate outward on an expanding trajectory, keeping pace with the decreasing magnetic field and increasing relativistic mass until the particles are swept out after a certain time (e.g., about 600 microseconds). Changing the duration that the particle source is activated changes the width of the particle pulse extracted from the plasma column during the frequency scan. Increasing the pulse width increases the number of particles extracted, thereby increasing the intensity of the particle beam. Conversely, reducing the pulse width results in a decrease in the number of particles extracted, resulting in a decrease in the intensity of the particle beam.

[0125] In another example technique, the intensity of a particle beam can be controlled by changing the voltage applied to a cathode in a particle source. In this regard, a plasma column is produced by applying a voltage to two cathodes of a particle source and outputting a gas such as hydrogen (H2) near the cathode. The voltage applied to the cathode ionizes hydrogen, and the background magnetic field aligns the ionized hydrogen, thereby producing a plasma column. Increasing the cathode voltage causes the amount of ions in the plasma column to increase, while reducing the cathode voltage causes the amount of ions in the plasma column to decrease. When there are more ions in the plasma column, more ions can be extracted during the RF voltage scan, thereby increasing the intensity of a particle beam. When there are fewer ions in the plasma column, fewer ions can be extracted during the RF voltage scan, thereby reducing the intensity of a particle beam.

[0126] In another example technique, the intensity of the particle beam can be controlled by changing the amount of hydrogen supplied to the particle source. For example, increasing the amount of hydrogen supplied to the particle source results in more ionization opportunities in the plasma column in response to the cathode voltage. Conversely, reducing the amount of hydrogen supplied to the particle source results in reduced ionization opportunities in the plasma column in response to the cathode voltage. As described above, when there are more particles in the plasma column, more particles are extracted during the RF voltage scan, thereby increasing the intensity of the particle beam. When there are fewer particles in the plasma column, fewer particles are extracted during the RF voltage scan, thereby reducing the intensity of the particle beam.

[0127] In another example technique, the intensity of the particle beam can be controlled by changing the amplitude of the RF voltage used to extract particles from the plasma column. For example, increasing the amplitude of the RF voltage results in more particles being extracted from the plasma column. Conversely, decreasing the amplitude of the RF voltage results in fewer particles being extracted from the plasma column. When more particles are extracted, the particle beam has a greater intensity than when fewer particles are extracted.

[0128] In another example technique, the intensity of the particle beam can be controlled by changing the start time during the frequency sweep at which the particle source is activated and, therefore, during the extraction of particles. More specifically, there is a limited window during the frequency sweep during which particles can be extracted from the plasma column. In an exemplary embodiment, the frequency is swept from about 135 MHz to about 90 MHz at a substantially constant dose rate. In this example, particles can be extracted at about the beginning of the downward slope between the start and end frequencies, for example, between 132 MHz and 131 MHz, respectively, and the particle source can be activated for a period of time, for example, about 0.1 microseconds (μs) to 100 μs (e.g., 1 μs to 10 μs or 1 μs to 40 μs). Changing the frequency at which the particle source is activated affects the number of particles extracted from the particle beam, thereby affecting the intensity of the particle beam.

[0129] In another example technique, pulse blanking can be used to control the intensity of the particle beam. In this regard, the RF frequency sweep is repeated multiple times per second (e.g., 500 times / second). The particle source can be activated at each frequency sweep (e.g., every 2ms). Pulse blanking reduces the number of particles extracted from the particle beam by not activating the particle source during each frequency sweep. In order to obtain maximum particle beam intensity, the particle source can be activated at each frequency sweep. In order to reduce the particle beam intensity, the particle source can be activated less frequently, such as every half, one third, one percent scan, etc.

[0130] In another example technique, the intensity of the particle beam can be controlled by applying a DC bias voltage to one or more D-shaped plates used to apply an RF voltage to the particle accelerator cavity. At this point, the particle accelerator includes an active D-shaped plate, which is a hollow metal structure with two semicircular surfaces that enclose a space in which protons are accelerated during rotation around a cavity surrounded by a magnetic yoke. The active D-shaped plate is driven by an RF signal applied to the end of an RF transmission line to apply an electric field to the space. As the distance of the accelerated particle beam from the geometric center increases, the RF field changes over time. The pseudo-D-shaped plate may include a rectangular metal wall having slots spaced apart near the exposed edges of the active D-shaped plate. In some embodiments, the pseudo-D-shaped plate is connected to a reference voltage at the vacuum chamber and the magnetic yoke.

[0131] Applying RF voltage in the presence of a strong magnetic field can result in a phenomenon called multi-pactoring, which can reduce the amplitude of the RF field and, in some cases, can result in an electrical short circuit. In order to reduce the amount of multi-pactoring and thereby maintain the RF field, a DC (direct current) bias voltage can be applied to the active dee plate and, in some embodiments, also to the dummy dee plate. In some embodiments, the differential DC bias voltage between the active dee plate and the dummy dee plate can be controlled to reduce multi-pactoring and thereby increase particle beam intensity. For example, in some embodiments, there may be a 50% difference between the DC bias voltages on the active dee plate and the dummy dee plate. In an exemplary embodiment, there is a -1.9 kilovolt DC bias voltage applied to the dummy dee plate and a -1.5 kilovolt DC bias voltage applied to the active dee plate.

[0132] In another example technique, the intensity of the particle beam can be controlled by controlling the rate at which the RF voltage is scanned, for example, the slope of the drop. By decreasing the slope, the time to extract particles from the plasma column can be increased. As a result, more particles can be extracted, thereby increasing the intensity of the particle beam. Vice versa, for example, by increasing the slope, the amount of time to extract particles from the plasma column can be reduced, which can result in a reduction in the intensity of the particle beam.

[0133] Implementations of the foregoing techniques for controlling the intensity of a particle beam are described in U.S. Patent No. 9,723,705, entitled "Controlling Intensity Of A Particle Beam," the contents of which are incorporated herein by reference.

[0134] The control system can also control (1103) the beam spot size of the particle beam. As described above, one or more scattering devices can be moved into the path of the particle beam to change its beam spot size. In some embodiments, the native beam spot size of the synchrocyclotron is the minimum beam spot size produced by the system. Because the particle beam intensity is also a function of the beam spot size, this beam spot size also produces the maximum particle beam intensity. In some embodiments, the system can produce a beam spot size less than 2 millimeters (mm) sigma. In some embodiments, the system can produce a beam spot size of at least 2mm. In some embodiments, the system can produce a beam spot size between 2mm sigma and 20mm sigma. In some embodiments, the system can produce a beam spot size greater than 20mm sigma. In some embodiments, operation 1103 can be omitted.

[0135] The control system controls (1104) the scanning magnet to move the particle beam to a path 24 through the target 21 according to the treatment plan, such as Figure 2 Controlling the scanning magnet may include: controlling the current passing through the scanning magnet coil ( Figure 6 and 7 ), the scanning magnet coils control the movement of the particle beam in the Cartesian X dimension; control the current through the scanning magnet coils, the scanning magnet coils control the movement of the particle beam in the Cartesian Y dimension, or both. In this position, the system delivers ultra-high dose rate radiation to a column extending along the particle beam path through the target. In this example, the column includes an inner portion of the target ( Figure 2 ). The column 25 is three-dimensional because it extends radially from the center of the beam spot to the periphery of the beam spot, and the column extends downward through the target. In some embodiments, the column extends through the entire target, such as Figure 2 In some embodiments, the cylinder only extends partially into the target. In some embodiments, the cylinder is completely inside the target. In some embodiments, the cylinder starts from one surface of the target and extends into the interior of the target but does not reach another surface of the target. In some embodiments, portions of adjacent cylinders overlap.

[0136] The column is treated (1105) with ultra-high dose rate radiation. Examples of ultra-high dose rate radiation are described herein, including but not limited to 1 Gray per second or higher for less than 5 seconds duration. When the particle beam is stationary, a control system controls the energy of the particle beam so that the particle beam treats the column in the target. Treating the column in the target includes changing the energy of the particle beam so that for each change in energy, a majority of the dose of protons in the particle beam (its Bragg peak) is deposited at a different depth within the target. As described herein, the energy of the particle beam can be changed by moving structures made of boron carbide or other particle energy-reducing materials into or out of the path of the particle beam, such as for Figures 12 to 19 and 35 to 44. It can be repeated Fig.11 All or some of the operations may be repeated to treat different cylinders on the radiation target. For example, operations 1102, 1103, 1104, and 1105 may be repeated for each cylinder to be treated on the radiation target.

[0137] In embodiments described below that use a variable energy synchrocyclotron (or other type of variable energy particle accelerator), the energy of the particle beam can be varied by varying the current through the synchrocyclotron main coil. In some embodiments, the energy of the particle beam is varied by moving structures such as the energy absorbing plates of the range modulator 460 into and out of the path of the particle beam. In this regard, since the treatment plan dictates the locations of the columns on the target, the energy absorbing plates of the range modulator can be pre-positioned near these locations in order to reduce the time it takes for the plates to be moved into and out of position. Reference Fig.12 , for example, plate 500 can be made of, for example, pure boron carbide or a boron carbide-graphite composite, and plate 500 can be positioned near column 501 in target 503 before starting to treat column 501 with radiation. The plate can be moved from this position into the particle beam, thereby reducing the distance the plate needs to travel. That is, plate 500 can be configured to be fully retracted into the range modulator. Prior to treatment, the plate can be partially or fully extended, so that it does not need to travel from its fully retracted position to reach the path of the particle beam.

[0138] As mentioned above, one or more plates can be controlled to move in and out of the path of the particle beam to change the energy of the particle beam. In an example, each of the one or more plates can move in or out of the path of the particle beam within 100ms or a shorter duration. In an example, each of the one or more plates can move in or out of the path of the particle beam within 50ms or a shorter duration. In an example, each of the one or more plates can move in or out of the path of the particle beam within 10ms or a shorter duration. In an example, each of the one or more plates can move in or out of the path of the particle beam within 20ms or a shorter duration or within 10ms or a shorter duration to move into or out of the path of the particle beam. As previously mentioned, the use of a linear motor can promote the rapid movement of the plate, although an electric motor can also be used. In this example, rapid movement includes movement of the order of tens of milliseconds.

[0139] One or more plates can be moved into and out of the path of the particle beam according to a sequence defined in the treatment plan. Fig.12 , 13 , 14 and 15, a particle beam 504 is positioned by a scanning system to treat a column 501 of a target 503 at an ultra-high dose rate. In this example, treatment is initially performed without a plate in the particle beam path in order to treat the gradually shallower portions of the column 501. This is shown in FIG. Fig.12 Thus, the deepest portion 502 of the cylinder 501 is treated. Fig.13 In FIG. 5 , plate 500a enters the path of particle beam 504 in the direction of arrow 505 to reduce the energy of the particle beam. In this plate configuration, the second deepest portion 506 of cylinder 501 is treated. Fig.14 In FIG. 5 , plate 500 b also enters the path of particle beam 504 in the direction of arrow 505 to further reduce the energy of the particle beam. In this plate configuration, the third deepest portion 508 of the treatment column 501 is treated. Fig.15 500c also enters the path of particle beam 504 in the direction of arrow 505 to further reduce the energy of the particle beam. In this plate configuration, the shallowest portion 510 of column 501 is treated. By varying the energy of particle beam 504 while it is stationary, the entire column 501 can be delivered with ultra-high dose rate radiation. Examples of ultra-high dose rates are provided herein.

[0140] The particle beams can be directed by the scanning magnets to a new path through the target to treat different columns of the target 503. The different columns may or may not be immediately adjacent to the column 501. In some embodiments, the beam spots of the particle beams may or may not overlap. For example, referring to Fig.16 , 17, 18 and 19, the particle beam 604 is positioned by the scanning system to treat the column 601 of the target 503 at an ultra-high dose rate. In this example, in order to treat the gradually deeper parts of the column 601, all plates 500a, 500b and 500c in the particle beam path are first treated. This is shown in Fig.16 Therefore, the shallowest portion 602 of the cylinder 601 is treated first. Fig.17 In FIG. 6 , plate 500c is moved out of the path of particle beam 604 in the direction of arrow 605 to increase the energy of the particle beam. In this plate configuration, the second shallowest portion 602 of cylinder 601 is treated. Fig.18 In FIG. 6 , plate 500 b is also moved out of the path of particle beam 604 in the direction of arrow 605 to further increase the energy of the particle beam. In this plate configuration, the third shallowest portion 608 of cylinder 601 is treated. Fig.19 604 to further increase the energy of the particle beam. In this plate configuration, the deepest portion 610 of the column 601 is treated. By varying the energy of the particle beam 604 while it is stationary, the entire column 601 can be delivered with ultra-high dose rate radiation.

[0141] In some embodiments, the plates need not be in order to treat the column. For example, plate 500a may be moved into the path of the particle beam first, followed by plate 500c, and then plate 500b.

[0142] During the delivery of ultra-high dose rate radiation to column 501 or 601, the intensity of particle beam 504 or 604 can be changed as needed to deliver the ultra-high dose rate radiation specified in the treatment plan. It is worth noting that during the delivery of ultra-high dose rate radiation to each column, the particle beam is stationary. For example, when ultra-high dose rate radiation is delivered to different depths within the column, the path of the particle beam does not change relative to the target and the particle beam does not move. After the ultra-high dose rate radiation is delivered to the column, the particle beam is directed onto a new path through the target. Then, the target is treated with a reference to the target. Fig.11 In the same manner as described, ultra-high dose rate radiation is applied on a new path. The process is repeated until all targets are treated with ultra-high dose rate radiation, or until a specified portion of the target is treated with ultra-high dose rate radiation. In some embodiments, as shown, the cylinders can be parallel, with some overlap or no overlap. In some embodiments, at least some of the cylinders may not be parallel, resulting in overlap. In some embodiments, multiple groups of cylinders can be applied to the same target or microvolume from different angles, thereby treating the target multiple times with radiation while preventing healthy tissue from being affected by the radiation more than once.

[0143] In some embodiments, the particle beam is no longer directed along a path that has already been treated with ultra-high dose rate radiation. For example, the particle beam steps from one path through the target 503 to another path. In this example, each column along the path extending into the target is treated only once with ultra-high dose rate radiation. The columns are not revisited and treated again. By treating the column only once with ultra-high dose rate radiation, healthy tissue above the target, and in some cases healthy tissue below the target, is less susceptible to damage from radiation. However, it is worth noting that the example systems described herein are not limited to treating each column only once with ultra-high dose rate radiation. For example, in some embodiments, each column can be revisited any appropriate number of times and subjected to one or more additional doses of ultra-high dose rate radiation. In addition, the example systems described herein are not limited to treating each column only with ultra-high dose rate radiation. For example, a column of a target can be treated as described herein using a radiation dose rate that is less than what is considered an ultra-high dose rate. For example, a column of a target can be treated as described herein using a radiation dose rate such as 0.1 Gray per second for a duration of one or more minutes as described herein. In some embodiments, such as Figure 2 The column-by-column treatment shown can be combined with Figure 1 For example, the target can be treated column by column and then treated layer by layer, or layer by layer and then treated column by column. In some embodiments, a portion of the target can be treated column by column and a portion of the target can be treated layer by layer with ultra-high dose rate radiation or less radiation in each case.

[0144] In some embodiments, to reduce treatment time, the energy absorbing plates of the range modulator can be ordered differently for different columns on the target. For example, for column 501, as shown in FIG. Figures 12 to 15 As explained, the plates can be sequentially moved into the particle beam. The particle beam can then be directed to treat adjacent or other columns 601 of the target. If the plates already cover the path of the particle beam, they can be sequentially moved out of the path of the particle beam, such as for Figures 16 to 19 As described. If the plates do not yet cover the path of the particle beam, the plates can be moved together to cover the path of the particle beam and then sequentially moved out of the path of the particle beam. Thus, for a first column, the plates can be moved sequentially to treat gradually shallower portions of the first column, such as layers. For a second column adjacent to the first column, the plates can be moved sequentially to continuously treat deeper portions of the second column, such as layers. This process can be repeated throughout the target for adjacent paths of the particle beam. In some embodiments, the movement of the plates can be incremental in the beam field; for example, based on beam spot size (e.g., on the order of millimeters) rather than from their fully retracted position. For example, the plates can be moved from a particle beam path to an adjacent particle beam path, rather than fully retracting and extending for each column.

[0145] In some embodiments, the energy absorbing plate can move in all or part of the beam field. In some examples, the beam field is the maximum range that the particle beam can move in a plane parallel to the treatment area on the patient. One or more plates can track the particle beam as the one or more plates move from the particle beam to an adjacent particle beam. For example, one or more plates can move with the movement of the particle beam so that the particle beam passes through the one or more plates as the plates move.

[0146] In some embodiments, a radiation dose less than the ultra-high (or FLASH) radiation dose rate can be applied layer by layer to the target using a range modifier having a structure such as a plate made of boron carbide, a polyhedron, or a curved three-dimensional shape. Figure 1 , the entire layer 10 of the target 11 can be treated with a particle beam 12 having an energy sufficient to deliver a dose to the layer 10 by moving the particle beam through the layer in the direction of arrow 15. The range adjuster can then be reconfigured, for example, a plate made of boron carbide can be moved out of the beam path to increase the energy level of the particle beam. A different layer 16 of the target 11 can then be treated in the same manner using a particle beam having a different energy sufficient to deliver a dose to the layer 16, and so on.

[0147] In some embodiments, a FLASH dose of radiation can be delivered along a single column with the beam direction fixed to a single beam spot at the center of a particle accelerator or the like. In some embodiments, a FLASH dose of radiation can be delivered using a slightly larger local volume, referred to as a microvolume, rather than a column aimed at a single beam spot. A microvolume can be a voxel, a portion of a voxel, or include multiple voxels as specified in the treatment plan. Figures 35 to 44 Examples of delivering radiation to a microvolume of an irradiation target through a column using a FLASH dose rate are shown. Examples of FLASH dose rates are described herein. In some embodiments, a microvolume of an irradiation target is delivered through a column. Figures 35 to 44 The microvolume delivered radiation can be a non-FLASH dose rate or a combination of FLASH dose rate and non-FLASH dose rate.

[0148] Fig.35 An example of a portion 1400 of a radiation target (e.g., a tumor in a patient) is shown. The portion 1400 is divided into four microvolumes 1401, 1402, 1403, and 1404. Although cubic microvolumes are shown, the microvolumes can have any suitable shape, such as a three-dimensional orthotope, a regularly curved shape, or an amorphous shape. In this example, each microvolume is formed by irradiating the target in a manner described herein, such as with reference to FIG. Figures 12 to 19, treating by delivering radiation through a column. For example, a column depth of a microvolume can be treated with radiation by changing the particle beam energy using a range adjuster plate or by controlling a variable energy synchrocyclotron to change the particle beam energy. After a single microvolume has been treated, the next microvolume is treated, and so on, until the entire radiation target has been treated. Treatment of the microvolumes can be performed in any suitable order or sequence.

[0149] exist Figures 35 to 46 In the example of , only eight columns 1405 are shown. However, any suitable number of columns may be treated in each microvolume. In some examples, 10 to 20 beam spots, and therefore columns, may be used to treat a microvolume. Furthermore, although each beam spot corresponds to a radiation column, only the front column is shown in the figure for clarity. Furthermore, although the examples described herein treat microvolumes from the deepest portion of the column to the shallowest portion of the column, this need not be the case. For example, the range adjuster plate may be controlled to treat one microvolume from the deepest portion of the column to the shallowest portion of the column, then treat an adjacent microvolume from the shallowest portion of the column to the deepest portion of the column, and so on, as described in reference to Figures 12 to 19 In other examples, different column depths may not be treated in sequence.

[0150] exist Fig.35 , the deepest portion 1407 of the cylinder 1405 is treated. The treated portion of the cylinder is shaded, and the untreated portion is not shaded, which is the convention used herein. Fig.36 , the next deepest portion 1408 of the treatment column 1405. Fig.37 , the next deepest portion 1409 of the treatment column 1405. Fig.38 , the next deepest portion 1410 of the treatment column 1405. Fig.39 , the shallowest portion 1411 of the cylinder 1405 is treated, thereby completing the treatment of the microvolume 1401. In this regard, although the cylinders are separated for clarity, the cylinders can actually overlap at least partially, such as for Figures 12 to 19 situation to ensure that the entire microvolume is treated with radiation.

[0151] After microvolume 1401 is treated, the next microvolume 1402 is treated in a similar manner. Fig.40 , the deepest portion 1417 of the treatment column 1415. Fig.41 , the next deepest portion 1418 of the treatment column 1415. Fig.42 , the next deepest portion 1419 of the treatment column 1415. Fig.43 , the next deepest portion 1420 of the treatment column 1415. Fig.44In the embodiment of the present invention, the shallowest portion 1421 of the cylinder 1415 is treated, thereby completing the treatment of the microvolume 1402. As described above, although the cylinders are separated for clarity, the cylinders can actually overlap at least partially, such as for Figures 12 to 19 situation to ensure that the entire microvolume is treated with radiation.

[0152] After microvolume 1402 is treated, the remaining microvolumes can be treated in a similar manner. The microvolumes can be treated in any order or sequence and using any appropriate number and position of pillars. In addition, as described herein, different particle beam intensities can be used to treat each pillar. These intensities can vary from pillar to pillar, or from microvolume to microvolume, or from pillar to microvolume. In addition, each microvolume can be treated from multiple different angles as part of intensity modulated proton therapy (IMPT).

[0153] In one example, Fig.45A and 45B The curves show the results of a Monte Carlo simulation that calculates the radiation dose delivered to the treatment volume and the time it takes for each voxel in the dose calculation to reach the final dose. In one example, with performance modifications to some parameters of the synchrocyclotron, such as 10 ms slice switching time instead of 50 ms slice switching time, increased particle beam current, and enhanced pulse-to-pulse stability, beam spots delivered on cubes that are 3 cm on each side can be delivered with each portion of the treatment volume receiving its dose in less than 500 milliseconds. These small cubes are not delivered strictly as cylinders with one beam spot per energy layer, but rather as micro-volumes with several (e.g., 10 to 20) beam spots per layer. In addition, collimation can be used to isolate one micro-volume from another, allowing the volumes to be delivered in a reasonable total treatment time. For example, the collimators described herein or any other suitable collimation device, including a standard multi-leaf collimator, can be used.

[0154] In some embodiments, each microvolume can be referenced Figures 12 to 19 For example, an entire column in a microvolume may be treated before moving to the next column in the same microvolume. Once all columns in the microvolume are treated, treatment proceeds to the next microvolume. There, treatment is repeated until all columns in the microvolume are treated. Treatment then proceeds to the next microvolume, and so on, until the entire radiation target is treated. These embodiments differ from Figures 35 to 44 The implementation method, in Figures 35 to 44 In an embodiment, for each pillar in a microvolume, the entire depth or microlayer of each pillar in the microvolume is treated at one time. Thereafter, treatment proceeds to the next depth, and so on, until all pillars in the microvolume are treated.

[0155] As described herein, delivering radiation to all or part of a column at a very high dose (FLASH) rate can be implemented to deposit radiation dose in any random manner. Fig.34 , an example column 1299 in the radiation target may include multiple depths. Each depth may include a microlayer of the target having a diameter of a large confined spot. Using delivery or radiation through the column as described herein, radiation may be delivered to each of the depths 1301, 1302, and 1303 at a super high dose (FLASH) rate. The dose may be provided in any manner determined by the treatment plan. For example, a higher dose of radiation may be applied to depth 1303 than to depths 1301 or 1302. In another example, the highest dose may be applied to depth 1303, the second highest dose may be applied to depth 1302, and the lowest dose may be applied to depth 1302. In another example, the highest dose may be applied to depth 1301, the second highest dose may be applied to depth 1303, and the lowest dose may be applied to depth 1302. Thus, the dose may be applied without regard to (e.g., independent of) the shape of the Bragg peak produced by summing multiple doses. In other words, in some cases, the dose may not be configured to obtain an extended Bragg peak along the column of radiation delivered to the radiation target at ultra-high dose (FLASH) rates or lower dose rates.

[0156] In some embodiments, one or more ridge filters or range modulator wheels can be added to the path of the particle beam to extend (e.g., elongate) the Bragg peak of the particle beam. The elongated or extended Bragg peak is produced by using a uniform depth-dose curve. That is, the dose is calibrated based on the tissue depth to which the dose will be delivered so as to obtain a flat or substantially flat elongated Bragg peak. Reference Fig.34 For example, to achieve an extended Bragg peak, such as 1300, using radiation delivery through a column, a full (100%) dose may be applied to a depth 1301 in the column 1299 of the irradiation target for a period of time. Next, 80% of the dose may be applied to a depth 1302 for a period of time. Depth 1302 is further upstream of the beam (i.e., shallower) than depth 1301. Next, 66% of the dose may be applied to a depth 1303 for a period of time. Depth 1303 is further upstream of the beam (i.e., shallower) than depth 1302. This may be repeated until the extended Bragg peak 1300 is obtained.

[0157] The motor can control the movement of one or more ridge filters or range modulator wheels into or out of the particle beam path. The motor can respond to commands from the control system. The Bragg peak of the expanded particle beam can be used, for example, Figures 12 to 19 The column treatment shown or Figure 1Layer-by-layer treatment is shown. In some embodiments, when the Bragg peak is expanded, the intensity of the particle beam can be increased using techniques such as those described herein.

[0158] In some embodiments, the two-dimensional or three-dimensional movement of the range modulator wheel within the beam field can be automatically controlled to track the movement of the particle beam. For example, the range modulator wheel can be automatically controlled to move in the X, Y, and / or Z dimensions of Cartesian. The range modulator wheel can have different thicknesses and can be rotated to change the Bragg peak of the particle beam, thereby changing the depth at which most particles are deposited in the target. In some embodiments, the range modulator wheel can include steps that define its various thicknesses. In some embodiments, the intensity of the particle beam can be controlled to control the dose delivered at each position on the range modulator wheel. This is done to control the depth dose distribution.

[0159] As mentioned above, the scanning system includes a collimator. The collimator can be controlled by the control system to shape the particle beam before the particle beam reaches a target in the patient. Fig. 20 An exemplary embodiment of a collimator 700 is shown that can be used with a particle therapy system such as described herein. The collimator 700 includes a carrier 702. In this example, the carrier is a plate; however, the carrier can have any suitable structure, such as a polyhedron or a three-dimensional curved structure, such as a cylinder, cone, or sphere. As previously described, the carrier can be made of a metal or other material, such as nickel, brass, or tungsten, with a thickness sufficient to prevent radiation of a given energy from passing through. For example, the carrier can be constructed to have a certain thickness and composition, such as to prevent proton beams with energies of 100 MeV, 150 MeV, 200 MeV, 250 MeV, or 300 MeV from passing through. In this example, the opening 704 in the carrier includes a two-dimensional 705 array of holes. In this example, the holes are circular; however, any suitable shape of holes can be used. For example, the holes can be elliptical, square, polygonal, or any other suitable shape. The size of the holes can be determined based on the size of the particle beam at the collimator location and based on the amount of trimming and collimation to be produced. In this regard, in some embodiments, the system can produce a beam spot size of 2 mm sigma to 20 mm sigma. The aperture can be formed to produce collimation within this range. As previously described, in some embodiments, the size and / or shape of the aperture is non-changeable or non-configurable. This can reduce the time required to reconfigure the system when delivering ultra-high dose rate radiation. In some embodiments, the size and / or shape of the aperture is configured to allow collimation after a predefined amount of particle beam expansion.

[0160] In some embodiments, the carrier can move within or across the entire beam field. As previously described, in some examples, the beam field is the maximum extent to which the particle beam can move in a plane parallel to the treatment area on the patient. Fig.21 In the exemplary collimator 720 of FIG. 708 , the carrier 708 can be mounted on a track 709 and connected to a belt 710 by a physical connection 711. A rotary motor 712 can drive the belt 710 to move the carrier along the track to position the carrier within the beam field. For example, the rotary motor 712 can respond to a command from the control system 114 (as shown by the dashed line 715) to position the carrier before treatment and leave the carrier in place during treatment. In an alternative embodiment, the motor can be a rotary motor that drives a corresponding linear actuator to control the movement of the carrier in at least part of the beam field. In some embodiments, the carrier can move during treatment. For example, the carrier can move based on the movement of the particle beam. For example, if the treatment area exceeds the size of the collimator, the collimator can be moved between treatments of the column by the motor 712 to position the collimator to treat an additional portion of the target. In another example, when the particle beam passes through the beam field, the collimator can move in unison with the movement of the particle beam, i.e., track the movement of the particle beam.

[0161] In some embodiments, the carrier can move in one, two, or three dimensions within the beam field. For example, as described above, the carrier can be mounted on a track to move through the beam field in one dimension. In some embodiments, the carrier can be automatically controlled to move in two or three dimensions within the beam field. In some embodiments, the track (and its associated components, such as motors and belts) to which the carrier is connected can itself be connected to a carriage (not shown), and the carrier can be controlled to move in a dimension perpendicular to the track. For example, the carriage can be controlled by a motor that responds to one or more commands from a control system. Thus, the control system can instruct the movement of the carrier along the track and the movement of the track through the carriage, thereby achieving two-dimensional movement of the carrier within the beam field.

[0162] In some embodiments, one or more encoders may be used to monitor or determine the movement of the carrier. In some examples, the encoder includes an electronic device connected to the carrier or a component or structure that moves with the carrier. The encoder may include one or more laser sensors, optical sensors, or diode sensors. The encoder detects the movement of the carrier, for example by detecting the position of a mark or other identifier on the carrier or on a structure connected to the carrier and moving with the carrier relative to the encoder. Information about the position of the carrier is fed back to the control system and used by the control system to confirm the position of the carrier and, in some embodiments, to change its position. The encoder may be or include a simple electronic sensor that is not particularly sensitive to neutron radiation and can therefore be located in the treatment room.

[0163] As previously described, in some embodiments, a collimator is used to implement a treatment plan to deliver ultra-high dose rate radiation to a target column in a patient. To this end, a control system can be configured to control movement of a particle beam toward a first aperture 716 of a collimator 720 so that at least a portion of the particle beam can reach the patient through the first aperture, change the energy of the particle beam while the particle beam remains stationary at the first aperture, and control movement of the particle beam from the first aperture 716 to a second aperture 717. In some embodiments, the center of the beam spot (e.g., the cross-sectional area of ​​the particle beam) is located at the center of each aperture. As described herein, the energy of a particle beam can be changed by moving an energy absorbing structure into or out of the path of the particle beam, or by changing the current through a superconducting magnet used in a variable energy particle accelerator. The movement (or "steering") of a particle beam can be changed by changing or not changing the direction of travel through a reference beam. Figures 4 to 7 The control system can also be configured to change the energy of the particle beam while the particle beam remains stationary at the second aperture 717, and control the movement of the particle beam from the second aperture 717 to a plurality of additional apertures, the sequence of which can be defined by the treatment plan. At each of the plurality of additional apertures, such as 721, 722, and 723, etc., the particle beam is controlled to remain stationary for a period of time while the energy of the particle beam is varied. As a result, at each aperture, the particle beam is trimmed, and due to the energy variation, the particle beam treats a three-dimensional column within the target, as described in reference Figure 2 , 12 to 19 and 35 to 44. As mentioned above, such as Fig.21 The openings of the holes can be positioned relative to each other to achieve a desired amount of overlap, or no overlap, between adjacent posts in the target.

[0164] In some embodiments, the collimator can be mounted in a nozzle on a gantry inside the system, an example of which is shown in FIG. Fig.26 , 27 and 28. In this regard, the collimator can be located downstream of the beam of the range adjuster relative to the particle accelerator. In other words, the collimator can be closer to the patient than the range adjuster. This is because the range adjuster can cause some dispersion of the particle beam, and this dispersion can be reduced or corrected by the collimator. The nozzle can be configured to move the collimator toward or away from the patient. In addition, the nozzle including the collimator can be fully retracted into the internal gantry so that the collimator does not hinder the technician from performing the treatment. In some embodiments, the internal gantry can be flush with the wall of the treatment room, in which case fully retracting the nozzle and collimator into the internal gantry will cause the nozzle and collimator to be fully retracted into the wall.

[0165] Fig. 22An exemplary embodiment of a collimator 725 is shown, which includes a single linear array of holes. In addition to the arrangement of the holes in a single linear array, the composition of the collimator 725 and the structure of the holes can be the same as that of the collimator 720. In this example, a carrier 726 including holes is mounted on a track 727 and connected to a belt 728. A rotary motor 730 drives the belt 728 clockwise or counterclockwise, which causes the carrier 726 to move in either direction of arrow 731 within a frame 732. When the particle beam moves to an area adjacent to the carrier 726, the motor 730 can move the carrier 731 in response to a command from a control system. In an example, the control system can be configured to control the movement of the particle beam to the first hole 735 of the collimator 725 so that at least a portion of the particle beam can reach the patient, change the energy of the particle beam while the particle beam remains stationary at the first hole, and control the movement of the particle beam from the first hole 735 to the second hole 736. The control system can also be configured to change the energy of the particle beam while the particle beam remains stationary at the second aperture 736, and control the particle beam to move downward from the second aperture 736 to a plurality of additional apertures in a linear array defined by the carrier 726. At each of the plurality of additional apertures, such as 737, 738, and 739, the particle beam is controlled to remain stationary for a period of time while the energy of the particle beam is changed, thereby treating the column within the target at all aperture locations.

[0166] When the particle beam is to be moved to another area, such as area 740 adjacent to the carrier, the carrier 726 can first be moved to cover that area so that the column within the target below that area can be treated with ultra-high dose rate radiation, as previously described. Fig.23 As shown, carrier 726 can be moved to region 740 and the particle beam can then be directed upward through the hole in the carrier to treat the column within the target, as previously described. This process can be repeated until the desired amount of targets have been treated with ultra-high dose rate radiation. Fig. 22 and 23 725 can be mounted to a carriage that is controllable to move in a dimension perpendicular to the track 727. For example, the carriage can be controlled by a motor that responds to one or more commands from a control system. Thus, the control system can direct movement of the carrier 726 along the track 727 and movement of the track 727 via the carriage, thereby achieving two-dimensional movement of the carrier within the beam field. As described above, the collimator can also be connected to the nozzle, thereby allowing additional dimensions of movement toward or away from the patient.

[0167] Fig.24 Shows Fig. 22 and 23A variation of the collimator 725 of the present invention. In this exemplary collimator 742, there are two carriers 744 and 745, each of which includes a linear array of holes. In addition to arranging the holes into two linear arrays, the composition of the collimator 742 and the structure of the holes can be the same as the collimator 725. In this example, the two carriers can be physically connected to move along the track 747 in coordination. As described above, the two carriers 744 and 745 are mounted on the track 747 and connected to the belt 749. The rotary motor 750 drives the belt 749 clockwise or counterclockwise, which causes the two carriers to move in either direction of the arrow 752 within the frame 753. The motor 750 can respond to commands from the control system to move the carrier to meet the treatment plan. In the example, the control system can be configured to control the movement of the particle beam to the first hole 755 of the carrier 744 so that at least a portion of the particle beam can reach the patient through the first hole, change the energy of the particle beam while the particle beam remains stationary at the first hole, and control the movement of the particle beam from the first hole 755 to the second hole 756. The control system can also be configured to change the energy of the particle beam while the particle beam remains stationary at the second aperture 756, and to control the particle beam to move downward from the second aperture 756 to a plurality of additional apertures in the linear array of apertures defined by the carrier 744. At each of the plurality of additional apertures, the particle beam is controlled to remain stationary for a period of time while the energy of the particle beam is changed, thereby treating a column within the target. Thereafter, the particle beam can be diverted to the carrier 745 and passed upward through the aperture in the carrier 745 to treat a column within the target below the carrier 745. This process can be repeated until a desired amount of the target has been treated using ultra-high dose rate radiation. Although Fig.24 747. Although not shown, the collimator 742 can be mounted on a carriage that can be controlled to move in a dimension perpendicular to the track 747. For example, the carriage can be controlled by a motor that responds to one or more commands from a control system. Thus, the control system can direct movement of the carrier along the track 747 and movement of the track 747 via the carriage to achieve two-dimensional movement of the carrier within the beam field. In some embodiments, different carriers 744 and 745 can be directly adjacent or in contact, or there can be a gap 758 between the two, such as Fig.24 As described above, a collimator may also be attached to the nozzle, thereby allowing an additional dimension of movement toward or away from the patient.

[0168] In some embodiments, Fig.25As shown, carriers 761 and 762 (which may have the same construction as carriers 744 and 745, respectively) may be mounted on separate rails 764 and 765, connected to separate belts 767 and 768, and controlled by separate rotation motors 770 and 771, each of which is responsive to commands from a control system. Thus, carriers 761 and 762 may be controlled to move independently and relative to each other to implement ultra-high dose rate radiation delivery according to a treatment plan. Each portion of collimator 760 and its associated components may have the same or similar structure and function as the corresponding portion of collimator 725.

[0169] Although in Fig.25 760 can be mounted to a carriage that is controllable to move in a dimension perpendicular to the rails 764 and 765. For example, the carriage can be controlled by a motor that responds to one or more commands from a control system. Thus, the control system can direct movement of the carrier along the rails 764 and 765 and movement of the rails 764 and 765 via the carriage, thereby achieving two-dimensional movement of the carrier within the beam field. In some embodiments, each of the carriers 761 and 762 can be mounted to a separate carriage, thereby enabling each of the carriers 761 and 762 to independently perform a second dimension of movement. As described above, the collimator can also be connected to the nozzle, thereby allowing additional dimensions of movement toward or away from the patient.

[0170] in this regard, Fig.24 and 25 Two carriers are shown, each carrier containing a single linear array of holes. In some embodiments, collimator 742 or 760 may include two or more carriers, each carrier containing a linear array of holes or a two-dimensional array of holes. Each carrier may be as shown. Fig.24 As in the physical connection to move together, or each carrier can be as Fig.25 In some embodiments, the two motors can be configured to move the carriers, such as carriers 761 and 762, along a single identical track that is independent of each other.

[0171] In some embodiments, the opening through which the particle beam passes may be a slot rather than a hole. An example slot is rectangular in shape and may extend above and across a location above the target where two or more beam spots of the particle beam are to be delivered. Figures 20 to 25 Any of the carriers shown in the embodiments of may include slots that are openings rather than holes. For example, Figures 20 to 25 Each linear array of holes in the can be replaced by a single slot or two or more adjacent slots. In this regard, Fig.30 An exemplary collimator 780 having an array of slots 781 is shown. In this example, the slots extend the entire length of the carrier. However, the slots may extend partially below the carrier. For example, referring to Fig.31 , the collimator 783 may include a two-dimensional array of slots 784 , with each individual slot extending approximately halfway down the carrier 783 .

[0172] The slots can be configured to shape and collimate the particle beam in one dimension. Fig.32 As shown, exemplary slots 788 collimate beam spot 790 by allowing portion 791 of the particle beam to pass through the patient and blocking portions 792 and 793 of the particle beam. At the ends of the slots, such as end 794, the particle beam can be collimated in two dimensions. As with the case of collimators using holes, collimators using slots can also be used to implement ultra-high dose rate radiation therapy.

[0173] For example, refer to Fig.33 In an exemplary collimator 800 of the embodiment of the present invention, the control system can control the movement of the particle beam to the first portion 801 of the slot 798 so that at least a portion of the particle beam can reach the patient, to change the energy of the particle beam while the particle beam remains stationary at the first portion 801 of the slot 798, and to control the movement of the particle beam from the first portion 801 of the slot 798 to the second portion 802 of the slot 798. The control system is also configured to change the energy of the particle beam while the particle beam remains stationary at the second portion 802 of the slot 798, and to control the movement of the particle beam from the second portion 802 of the slot 798 to multiple additional portions 803 and 804 of the slot 798. For example, the particle beam can move along the slot 798 and deliver radiation at discrete locations along the slot. The particle beam is controlled to remain stationary for a period of time at each of the multiple additional portions of the slot while the energy of the particle beam is changed at each portion, thereby treating the column of the target. The particle beam can then move to the portion 805 of the slot 799 and travel upward along the slot 799, depositing radiation in the column. Therefore, a collimator using slots as openings can still be used to deliver ultra-high dose rate radiation to a target in a patient through a column. By controlling the current through the scanning magnets to position the beam spots at appropriate locations, the overlap between adjacent beam spots of the particle beam can be controlled in the treatment plan. In some embodiments, the use of slots can increase the treatment speed and reduce stray neutrons generated when the proton beam is trimmed.

[0174] Although for example Figures 20 to 25 The various embodiments of the collimators described in and 30 to 33 are described for use with ultra-high dose rate radiation therapy columns, but any embodiment of such collimators can be used to deliver radiation doses that are not ultra-high dose rates and / or that are not delivered in columns. For example, any of the collimators described herein can be used to implement reference Figure 1 The described layer-by-layer scanning method. In addition, the described collimator embodiments show openings with the same shape, which are regularly arranged on the carrier. In some embodiments, the openings on the same carrier can have different sizes and / or shapes, which can be determined by, for example, the treatment plan. In addition, the openings can be arranged in an irregular pattern, which can be determined by, for example, the treatment plan. In some embodiments, the carrier can include only holes, only slots, or a combination of slots and holes. In some embodiments, the carrier can have a single opening, such as a hole or a slot. The carrier and the particle beam can move together.

[0175] In some embodiments, an exemplary particle therapy system may include a configurable collimator, in lieu of or in addition to a collimator. Figures 20 to 25 and 30 to 33. An example of a configurable collimator that may be used is described in U.S. Patent Publication No. 2017 / 0128746, entitled “Adaptive Aperture,” the contents of which are incorporated herein by reference.

[0176] Fig.46 An example of a blade 859 that can be used in a configurable collimator is shown, although the configurable collimator is not limited to use with this type of blade. The height 850 of the blade is along the particle beam line (e.g., the direction of the particle beam). The length 852 of the blade is in and out of the treatment area along its actuation direction and is based on the size of the field or portion thereof that the system is capable of treating. The size of the field corresponds to the treatment area that the particle beam is capable of affecting. The width 853 of the blade is the direction in which multiple blades are stacked when actuated. Generally, the more blades used, the higher the aperture resolution that can be produced, including curved boundaries.

[0177] exist Fig.46 8, blade 859 includes tongue-and-groove features 855 along its sides that are configured to reduce inter-leaf leakage when multiple such blades are stacked. In this example, the curved end 856 of blade 859 is configured to maintain a surface tangential to the particle beam at all locations in the treatment area. The tip of each blade can be flat rather than curved.

[0178] In some embodiments, the height of the configurable collimator blades is sufficient to block at least the maximum beam energy (e.g., the maximum energy of the particle beam output by the accelerator). In some embodiments, the configurable collimator blades have a height that blocks less than the maximum particle beam energy. In some embodiments, the length of the configurable collimator blades is not determined by the area of ​​the entire treatment area, but is determined by the area of ​​a single beam spot (cross-sectional area of ​​the particle beam) or multiple beam spots.

[0179] Fig.47An exemplary embodiment of a partially configurable collimator 810 is shown. The configurable collimator 810 includes blades 811, which have a certain height and are made of materials such as nickel, brass, tungsten or other metals, sufficient to inhibit or prevent radiation of a given energy from passing through. For example, in some systems, a particle accelerator is configured to produce a particle beam with a maximum energy of 100MeV (million electron volts) to 300MeV. Therefore, in such a system, the blades can be configured to prevent particle beams with energies such as 100MeV, 150MeV, 200MeV, 250MeV, 300MeV from passing through. For example, in some systems, a particle accelerator is configured to produce a particle beam with a maximum energy exceeding 70MeV. Therefore, in such a system, the blades can be configured to prevent particle beams with energies of 70MeV or higher from passing through.

[0180] The blades 811 are mounted on a carrier to control their movement relative to a treatment area of ​​a radiation target, such as a cross-sectional layer of a tumor in a patient. The movement is controlled so that the blades 811 cover some portions of the treatment area 814, thereby preventing the radiation from affecting these portions during treatment, while exposing other portions of the treatment area to the radiation. Fig.47 In the exemplary embodiment of the present invention, there are fourteen blades in total, seven on the left and seven on the right. In some embodiments, there may be a different number of blades, for example, ten in total, five on the left and five on the right; twelve in total, six on the left and six on the right, and so on.

[0181] exist Fig.47 In FIG. 8 , position 812 represents the center of the beam spot and therefore represents the position of the cylinder in the target to which radiation will be delivered. Circle 818 represents a portion of the treatment boundary beyond which radiation should not be delivered. Beam spots close to this boundary (e.g., within one standard deviation of the particle beam profile) border healthy tissue. These beam spots can be trimmed (i.e., blocked) by appropriately configuring and placing leaves on the configurable collimator. An example of a beam spot to be trimmed is beam spot 816, which is centered at position 816. As shown, leaves 811 are configured to block portions of beam spot 816 that extend beyond circle 818 and into healthy tissue (or at least tissue that is not designated for treatment).

[0182] In an exemplary embodiment, on each of two separate carriers, there are five blades of about 5 mm width and two blades of about 81 mm width. In some embodiments, on each of two separate carriers, there are seven blades, two of which are three times or more the width of the other five blades. Other embodiments may include blades of different numbers, sizes, and configurations, as well as carriers of different numbers and configurations. For example, some embodiments may include any number of blades between five and fifty per carrier, such as 5, 6, 7, 8, 9, 10, 11, 2, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, or 50 blades (or more) per carrier.

[0183] As described herein, the carriages can move horizontally and vertically. The blades can also move horizontally into and out of the treatment area relative to each carriage. In this manner, the blades can be configured to approximate the shape of a treatment boundary in an area near the area being treated (e.g., circle 816 or a portion thereof in this example).

[0184] The blades can be moved vertically and / or horizontally between different columns to be treated so that the blades are in the proper position when the particle beam is delivered to a particular column. As described above, when the particle beam is stationary, the blades can be reconfigured based on the particle beam energy to provide different configurations for different particle beam energies. As previously described, the particle beam may be dispersed in the tissue. The configurable collimator can be reconfigured as the particle beam energy changes to maintain a regular (e.g., cylindrical) shaped column.

[0185] Fig.48 , 49 50 show an exemplary embodiment of a configurable collimator, including brackets 913, 914, 915 configured to hold and move the leaves vertically and horizontally relative to the treatment target. As shown, vertical movement includes movement in the Cartesian Z dimension 917, and horizontal movement includes movement in the Cartesian X dimension 918 (into or out of the Cartesian Y dimension). Fig.49 in the ). Fig.49 and 50 Portions of a transparent carrier housing are shown in order to illustrate components inside the housing; however, the housing is not actually transparent.

[0186] Bracket 913 is referred to as a main bracket, and brackets 914 and 915 are referred to as sub-brackets. Sub-brackets 914 and 915 are connected to main bracket 913, such as Figures 48 to 50As shown. In this example, the sub-brackets 914, 915 each include a housing fixed to the main bracket 915 via corresponding members 918, 919. In this example, the main bracket 913 can move vertically (Z direction) along the track 920 relative to the radiation target and relative to the particle accelerator. The vertical movement of the main bracket 913 also causes the sub-brackets to move vertically. In some embodiments, the sub-brackets move vertically in unison. In some embodiments, the vertical movement of each sub-bracket is independent of the vertical movement of another sub-bracket.

[0187] like Figures 48 to 50 As shown, each sub-bracket 914, 915 is connected to a corresponding rod or track 922, 923 along which the sub-bracket moves. More specifically, in this example, motor 925 drives sub-bracket 914 to move along rod 922 toward or away from sub-bracket 915. Similarly, in this example, motor 926 drives sub-bracket 915 to move along rod 923 toward or away from sub-bracket 914. As described herein, the movement of the main bracket and the sub-bracket is controlled to position the blade relative to the radiation target. In addition, the blade itself is also configured to move in and out of the bracket, also as described herein.

[0188] like Fig.50 As shown, the motor 930 drives the vertical movement of the main bracket 913. For example, Fig.50 As shown, the lead screw 931 is connected to a housing 932, which holds motors 925, 926 for driving the respective sub-carriages 914, 915 and is mounted on a track 920. The lead screw 931 is connected to the motor 930 and is driven vertically by the motor 930. That is, the motor 930 drives the lead screw 931 vertically (Cartesian Z dimension). Because the lead screw 931 is fixed to the housing 932, this movement also causes the housing 932, and thus the second carriage 914, 915, to move along the track 920 toward or away from the radiation target.

[0189] In this exemplary embodiment, as described above, seven blades 935, 936 are mounted on each sub-bracket 914, 915. Each sub-bracket can be configured to move its blade horizontally into or out of the treatment area. A single blade on each sub-bracket can be independently and linearly moved in the X dimension relative to other blades on the same sub-bracket using a linear motor. In some embodiments, the blades can also be configured to move in the Y dimension. In addition, the blades on one sub-bracket 914 can be moved independently of the blades on another sub-bracket 915. These independent movements of the blades on the sub-brackets, together with the vertical movement achieved by the main bracket, allow the blades to be moved into various configurations. As a result, the blades can conform to a randomly shaped treatment area in the horizontal and vertical dimensions in the horizontal and vertical directions. The size and shape of the blades can be varied to produce different configurations. For example, the size and shape can be changed to treat a single beam spot, thereby treating a single column. In some embodiments, a single blade on each sub-bracket can be independently and linearly moved using a motor that drives a lead screw in the X dimension relative to other blades on the same sub-bracket.

[0190] The blades can be made of any suitable material that prevents or inhibits the propagation of radiation. The type of radiation used can determine the material(s) used in the blades. For example, if the radiation is X-rays, the blades can be made of lead. In the examples described herein, the radiation is a proton or ion beam. Therefore, different types of metals or other materials can be used for the blades. For example, the blades can be made of nickel, tungsten, lead, brass, steel, iron, or any suitable combination thereof. The height of each blade can determine the degree to which the blade inhibits the transmission of radiation.

[0191] In some embodiments, the blades can have the same height, while in other embodiments, the height of some blades can be different from the height of other blades. For example, the height of a group of blades can be 5mm each. However, any suitable height can be used. For example, blades 935, 936 can have any of the following heights (or other heights): 1mm, 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, 11mm, 3mm, 13mm, 14mm, 15mm, 16mm, 17mm, 18mm, 19mm, 20mm, 21mm, 22mm, 23mm, 24mm, 25mm, 26mm, 27mm, 28mm, 29mm, etc. The blades can have any combination of the aforementioned heights. In addition, each blade can have a height that is different from one or more other blades.

[0192] In some embodiments, the height of the blades is not only sufficient to completely block the particle beam at the maximum expected proton energy (e.g., 3.3 cm of tungsten at 230 MeV or, for example, 5.2 cm of nickel), but also has enough additional material to prevent proton transport between the blades. This material can have a Fig.46 The tongue-and-groove structure shown, or a similar structure. The blade tip can be configured to include a curved or tapered surface to enhance the transport penumbra of proton beams of varying divergence.

[0193] In some embodiments, there can be more than one main carriage and corresponding motors and tracks. For example, a first main carriage can control the vertical movement of a first sub-carriage, and a second main carriage can control the vertical movement of a second sub-carriage. Thus, in such an embodiment, the two sub-carriages can move independently in the vertical direction if desired. In any case, the main carriage can be controlled by a computer. For example, executable instructions are stored in a computer memory (e.g., one or more non-transitory machine-readable storage media) and executed by one or more processing devices to control movement. Control can be performed with or without user input during treatment.

[0194] As described above, each sub-bracket 914, 915 includes a corresponding motor to control horizontal bracket movement. In some embodiments, all blades on a single bracket can be moved independently using linear motors, with one linear motor controlling each blade. Each blade can be controlled by Fig.10 The linear motors of the type described in the configurable collimator are controlled to produce an edge to block at least some radiation from reaching a patient, for example, to shape one or more beam spots produced by a particle beam. As described above, the linear motors used in the configurable collimator can have the same structure and function as the linear motors used in the range modulator. However, in this case, the collimator blades are attached to the linear motors instead of the energy absorbing plates. Each linear motor linearly drives its corresponding blade to its position in the configured edge.

[0195] In the exemplary embodiment described above, each blade is independently actuated using an independent and independently controllable linear motor so that any suitable shape can be depicted with the blade configuration. However, such flexibility may not be required to achieve acceptable edge consistency. The blades may be mechanically limited to only a limited number of configurations. For example, the blades may be limited to arranging them in vertical lines, front diagonal shapes, rear diagonal shapes, concave shapes, convex shapes, or any other achievable shape. In this way, flexibility can be traded for mechanical simplicity.

[0196] In some cases, better beam performance (penumbra or edge sharpness) results when the beam is tangent to the surface at the edge of the blade. However, since the beam is effectively originating from a single point source, the angle at which the beam passes through the plane of the configurable collimator changes as it moves away from the center of the field. For this reason, the blades may have curved edges, such as Fig.46 As shown, the edges can always be placed in a position that makes them tangential to the particle beam. In an exemplary embodiment of the configurable collimator, the track on which the main and auxiliary brackets move is curved so that flat blade edges can be used instead of curved blade edges and made flat but remain tangential to the particle beam.

[0197] In summary, in some embodiments, a configurable collimator can have a relatively small size, at least in part due to the linear motors described herein. Thus, compared to a standard multi-leaf collimator, an exemplary configurable collimator can be used to trim a portion of a treatment area at a time, such as an area that is less than the entire treatment area and is approximately equal to one beam spot size, two beam spot sizes, three beam spot sizes, four beam spot sizes, five beam spot sizes, etc. Thus, in some embodiments, a configurable collimator can be small enough to trim a single beam spot at a time, and can be large enough to trim several beam spots at one location, rather than the entire field (without moving). As described above, the ability to trim a single beam spot can be used to maintain a regular shape of the treatment column when the energy of the particle beam used to generate the treatment column varies.

[0198] The scanning system may include a configurable collimator as described herein that can be placed relative to the radiation target to limit the range of the particle beam, thereby limiting the range of the particle beam. For example, the configurable collimator can be placed in the particle beam downstream of the range adjuster and before the particle beam strikes the treatment area of ​​the radiation target. The configurable collimator is controllable to allow the particle beam to pass therethrough and then strike a specific portion of the treatment area while preventing the particle beam from striking other portions of the patient. Fig.51 The placement of an embodiment of a configurable collimator 970 is depicted relative to a patient 971. The direction of a particle beam 971 is also shown.

[0199] Fig.26 and 27 A portion of an example of a proton therapy system 1082 that includes a particle accelerator mounted on a gantry is shown. Because the accelerator is mounted on a gantry, it is in or adjacent to the treatment room. The particle accelerator may be Figure 3of a synchrocyclotron; however, the system is not limited to use with a synchrocyclotron. The gantry and particle accelerator can be controlled together with the scanning system to treat a column of irradiation targets using ultra-high dose rate radiation in the manner described herein. In some embodiments, the gantry is made of steel and has two legs (not shown) mounted to rotate on two corresponding bearings located on opposite sides of the patient. The gantry may include a steel truss (not shown) connected to each of its legs, the steel truss being long enough to span the treatment area where the patient is located and attached to the rotating legs of the gantry at both ends. The particle accelerator can be supported by the steel truss for movement around the patient.

[0200] exist Fig.26 and 27 In the example of FIG. 1084 , a patient is positioned on a treatment couch 1084 . In this example, the treatment couch 1084 includes a platform that supports the patient. The platform may also include one or more restraints (not shown) for holding the patient in place and for keeping the patient substantially immobile during movement of the treatment couch and during treatment. The platform may or may not be padded and / or have a shape (e.g., an indentation) that corresponds to a portion of the patient's shape. The couch may be moved by arms 1085 .

[0201] Fig.28 An example of a gantry configuration described in U.S. Patent No. 7,728,311, which is incorporated herein by reference, and includes components of an alternative embodiment of a proton therapy system that can be used to treat a column of irradiation targets using ultra-high dose rate radiation in the manner described herein. Fig.28 An example proton therapy system includes an internal gantry 1190 having an orifice 1191, a treatment couch 1192, and a particle accelerator 1193 (e.g., a synchrocyclotron of the type described herein) mounted on an external gantry 1194 for at least partially rotating around a patient to deliver radiation to a target(s) within the patient. The treatment couch 1192 is controllable and configured to rotate and translate the patient in the manner described herein.

[0202] exist Fig.28 In the example of FIG. 1 , the particle accelerator 1193 is also mounted to an external gantry 1194, which also enables the particle accelerator to be linearly moved (e.g., translated) along the arm 1196 in the direction of the arrow 1195. Fig.28 As shown, the particle accelerator 1193 can be connected to a universal joint 1199 for pivotal movement relative to the gantry. This pivotal movement can be used to position the accelerator and thus position the particle beam for treatment.

[0203] Components of the scanning system, including scanning magnets, ion chambers, range modulators, and collimators, can be mounted on, in, or coupled to the nozzles 1081, 1191 of the internal gantry of the proton therapy system. These components can be controlled by a control system to treat a column of irradiation targets using ultra-high dose rate radiation. In both examples, the nozzle can be moved along a track of the internal gantry (1080 or 1190) relative to the patient and the particle accelerator, and can be extended toward and retracted away from the patient, thereby also extending and retracting the components mounted thereon.

[0204] In some embodiments, the synchrocyclotron used in the proton therapy system described herein can be a variable energy synchrocyclotron. In some embodiments, the variable energy synchrocyclotron is configured to change the energy of the output particle beam by changing the magnetic field in which the particle beam is accelerated. For example, the current can be set to any one of a plurality of values ​​to generate a corresponding magnetic field. In an exemplary embodiment, one or more groups of superconducting coils receive a variable current to generate a variable magnetic field in a cavity. In some examples, one group of coils receives a fixed current, and one or more groups of other coils receive a variable current, so that the total current received by the coil group changes. In some embodiments, all coil groups are superconducting. In some embodiments, some coil groups (e.g., coil groups for fixed current) are superconducting, while other coil groups (e.g., one or more coil groups for variable current) are non-superconducting (e.g., copper) coils.

[0205] Generally speaking, in a variable energy synchrocyclotron, the magnitude of the magnetic field can vary with the magnitude of the current. Adjusting the total current of the coil within a predetermined range can produce a magnetic field that varies within a corresponding predetermined range. In some examples, continuous adjustment of the current can result in continuous changes in the magnetic field and continuous changes in the output beam energy. Alternatively, when the current applied to the coil is adjusted in a discontinuous, step-by-step manner, the magnetic field and the output beam energy also change accordingly in a discontinuous (step-by-step) manner. The ratio of the magnetic field to the current can allow relatively accurate changes in particle beam energy, thereby reducing the need for a range regulator. An example of a variable energy synchrocyclotron that can be used in the particle therapy system described herein is described in U.S. Patent No. 9,730,308, entitled "Particle Accelerator That Produces Charged Particles Having Variable Energies," the contents of which are incorporated herein by reference.

[0206] In an implementation of a particle therapy system using a variable energy synchrocyclotron, the energy of the particle beam can be controlled by changing the energy of the particle beam output by the synchrocyclotron to treat a column of a target. In such an implementation, a range modulator may or may not be used. For example, controlling the energy of the particle beam may include setting a current in a synchrocyclotron main coil to one of a plurality of values, each value corresponding to a different energy of the particle beam output from the synchrocyclotron. A range modulator may be used with a variable energy synchrocyclotron to provide additional energy variation, for example, between discrete energy levels provided by the synchrocyclotron.

[0207] In some embodiments, particle accelerators other than synchrocyclotrons can be used in the particle therapy systems described herein. For example, cyclotrons, synchrotrons, linear accelerators, etc. can replace the synchrocyclotrons described herein. Although a rotating gantry (e.g., an external gantry) has been described, the exemplary particle therapy systems described herein are not limited to use with a rotating gantry. Instead, the particle accelerator can be appropriately mounted on any type of robot or other controllable mechanism to achieve movement of the particle accelerator, which is also described as a gantry type. For example, the particle accelerator can be mounted on one or more robotic arms to achieve rotation, pivoting, and / or translational movement of the accelerator relative to the patient. In some embodiments, the particle accelerator can be mounted on a track, and the movement along the track can be controlled by a computer. In this configuration, the rotation and / or translation and / or pivoting movement of the accelerator relative to the patient can also be achieved by appropriate computer control. In some embodiments, the particle accelerator can be stationary and located outside the treatment room, and the beam is delivered to the nozzle in the treatment room.

[0208] In some examples, as described above, ultra-high dose rate radiation may include a radiation dose of more than 1 Gray per second for a duration of less than 500 ms. In some examples, ultra-high dose rate radiation may include a radiation dose of more than 1 Gray per second for a duration between 10 ms and 5 s. In some examples, ultra-high dose rate radiation may include a radiation dose of more than 1 Gray per second for a duration of less than 5 s.

[0209] In some examples, ultra-high dose rate radiation includes a radiation dose exceeding one of the following doses for a duration of less than 500 milliseconds: 2 Grays per second, 3 Grays per second, 4 Grays per second, 5 Grays per second, 6 Grays per second, 7 Grays per second, 8 Grays per second, 9 Grays per second, 10 Grays per second, 11 Grays per second, 12 Grays per second, 13 Grays per second, 14 Grays per second, 15 Grays per second, 16 Grays per second, 17 Grays per second, 18 Grays per second, 19 Grays per second, 20 Grays per second, 30 Grays per second, 40 Grays per second, 50 Grays per second, 60 Grays per second, 70 Grays per second, 80 Grays per second, 90 Grays per second, or 100 Grays per second. In some examples, ultra-high dose rate radiation includes a radiation dose exceeding one of the following doses over a duration between 10 ms and 5 s: 2 Gray per second, 3 Gray per second, 4 Gray per second, 5 Gray per second, 6 Gray per second, 7 Gray per second, 8 Gray per second, 9 Gray per second, 10 Gray per second, 11 Gray per second, 12 Gray per second, 13 Gray per second, 14 Gray per second, 15 Gray per second, 16 Gray per second, 17 Gray per second, 18 Gray per second, 19 Gray per second, 20 Gray per second, 30 Gray per second, 40 Gray per second, 50 Gray per second, 60 Gray per second, 70 Gray per second, 80 Gray per second, 90 Gray per second, or 100 Gray per second. In some examples, ultra-high dose rate radiation includes a radiation dose exceeding one of the following doses in a duration of less than 5 seconds: 2 Gray per second, 3 Gray per second, 4 Gray per second, 5 Gray per second, 6 Gray per second, 7 Gray per second, 8 Gray per second, 9 Gray per second, 10 Gray per second, 11 Gray per second, 12 Gray per second, 13 Gray per second, 14 Gray per second, 15 Gray per second, 16 Gray per second, 17 Gray per second, 18 Gray per second, 19 Gray per second, 20 Gray per second, 30 Gray per second, 40 Gray per second, 50 Gray per second, 60 Gray per second, 70 Gray per second, 80 Gray per second, 90 Gray per second, or 100 Gray per second.

[0210] In some examples, ultra-high dose rate radiation includes radiation doses exceeding one or more of the following doses: 100 Gray per second, 200 Gray per second, 300 Gray per second, 400 Gray per second, 500 Gray per second, or 600 Gray per second for a duration of less than 500 milliseconds, a duration of 10 milliseconds to 5 seconds, or a duration of less than 5 seconds.

[0211] In some examples, the ultra-high dose rate radiation includes a radiation dose of 20 Gray per second to 100 Gray per second for a duration of less than 500 ms. In some examples, the ultra-high dose rate radiation includes a radiation dose of 20 Gray per second to 100 Gray per second for a duration between 10 ms and 5 s. In some examples, the ultra-high dose rate radiation includes a radiation dose of 20 Gray per second to 100 Gray per second for a duration of less than 5 s. In some examples, the ultra-high dose rate radiation includes a radiation dose of 40 Gray per second to 120 Gray per second for a duration of, for example, less than 5 s. Other examples of time periods are as described above.

[0212] In some embodiments, the size, shape, or both of the apertures in the collimators described herein can be variable or configurable, e.g., the position of one or more apertures or slots can be moved. For example, one or more apertures or slots can be formed using fingers or blades mounted on one or more carriers, e.g., as described in U.S. Patent Application 2017 / 0128746 entitled “Adaptive Aperture”.

[0213] The operation of the example proton therapy systems described herein, and the operation of all or some of their components, may be controlled at least in part (where appropriate) using one or more computer program products, such as one or more computer programs tangibly embodied in one or more non-transitory machine-readable media, for execution by one or more data processing devices, such as programmable processors, computers, multiple computers, and / or programmable logic components, or to control their operation.

[0214] A computer program may be written in any form of programming language, including compiled or interpreted languages, and it may be deployed in any form, including as a stand-alone program or as a module, component, subroutine or other unit suitable for use in a computing environment. A computer program may be deployed to be executed on one computer or on multiple computers at one site, or distributed across multiple sites and interconnected by a network.

[0215] The actions associated with controlling all or part of the operation of the example proton therapy systems described herein can be performed by one or more programmable processors executing one or more computer programs to perform the functions described herein. All or part of the operations can be controlled using dedicated logic circuits, for example, FPGAs and / or ASICs (application specific integrated circuits).

[0216] Processors suitable for executing computer programs include, for example, general and special purpose microprocessors, and any one or more processors of any type of digital computer. Typically, the processor will receive instructions and data from a read-only storage area or a random access storage area or both. Elements of a computer (including a server) include one or more processors for executing instructions and one or more storage area devices for storing instructions and data. Typically, a computer will also include or be operably connected to one or more machine-readable storage media for storing data, such as magnetic disks, magneto-optical disks, or optical disks, to receive data from them, or to transmit data to them, or both. Non-transitory machine-readable storage media suitable for storing computer program instructions and data include all forms of non-volatile storage areas, including, for example, semiconductor storage area devices, such as EPROM, EEPROM, and flash storage area devices; magnetic disks, such as internal hard disks or removable disks; magneto-optical disks; and CD-ROMs and DVD-ROMs.

[0217] Any two or more of the foregoing embodiments may be used in appropriate combination with an appropriate particle accelerator (e.g., a synchrocyclotron). Similarly, any two or more of the individual features of the foregoing embodiments may be used in appropriate combination. Elements may be excluded from processes, systems, devices, etc. without adversely affecting their operation. Various individual elements may be combined into one or more individual elements to perform the functions described herein.

Claims

1. A particle therapy system, comprising: particle accelerators, used to generate particle beams to treat patients; a collimator including one opening or a plurality of openings, the collimator including a material that inhibits particle beam transport and the collimator being located between the particle accelerator and the patient; a plurality of structures, each structure of the plurality of structures for changing the energy of the particle beam as the particle beam passes through the structure, each structure of the plurality of structures comprising boron carbide; and a control system for controlling movement of particles to move within the one opening or between the plurality of openings, each opening shaping the particle beam in a manner that allows a portion of the particle beam to pass through the opening to reach a target in the patient, the control system being configured to control movement of one or more of the plurality of structures into or out of a beam field of the particle beam to treat a depth of each pillar in the microvolume, and thereafter treatment proceeds to a next depth of each pillar in the microvolume until all pillars in the microvolume are treated; Wherein, at the opening or each of the plurality of openings, the particle beam delivers a radiation dose to the target at an ultra-high dose rate. 2 . The particle therapy system of claim 1 , wherein the opening comprises an array of holes, the first opening comprises a first hole, and the second opening comprises a second hole. 3 . The particle therapy system of claim 1 , wherein the opening comprises an array of slots, the first opening comprising a first slot, and the second opening comprising a second slot.

4. The particle therapy system of claim 1 , wherein the plurality of structures are part of a range adjuster between a particle accelerator and a patient; The control system is configured to control the movement of the plurality of structures into or out of a particle beam path to change the energy of the particle beam.

5. The particle therapy system of claim 4, wherein the plurality of structures includes plates for changing the energy of the particle beam as it passes through the one or more plates.

6. The particle therapy system of claim 1 , wherein the particle accelerator comprises a superconducting magnet comprising conductive coils; and The control system is configured to vary the current through the conductive coil to vary the energy of the particle beam.

7. The particle therapy system according to claim 1, wherein: The particle beam delivers a radiation dose of more than 1 Gray per second to the target for less than 5 seconds.

8. The particle therapy system according to claim 1, wherein: The particle beam delivers a radiation dose of 20 Gray per second to 100 Gray per second to the target for a duration of 10 milliseconds to 5 seconds.

9. The particle therapy system according to claim 1, wherein: The particle beam delivers a radiation dose of 40 Gray per second to 120 Gray per second to the target for less than 5 seconds.

10. The particle therapy system of claim 1, wherein the openings comprise holes, the first opening comprises a first hole, and the second opening comprises a second hole; and Wherein controlling movement of the particle beam toward the first aperture and then toward the second aperture includes centering the particle beam at the first aperture and then centering the particle beam at the second aperture.

11. The particle therapy system according to claim 1, further comprising: a scanning magnet including conductive coils for generating a magnetic field to affect movement of the particle beam; The control system is configured to affect the magnetic field by changing the current flowing through the conductive coils of the scanning magnet, thereby controlling the movement of the particle beam.

12. The particle therapy system according to claim 1, further comprising: a track on which the collimator is mounted for movement within a beam field of the particle beam; and A motor is configured to move the collimator along the track.

13. The particle therapy system according to claim 12, wherein: The control system is configured to control the motor to move the collimator along the track based on the movement of the particle beam.

14. The particle therapy system according to claim 1, further comprising: Ridge filter, used to expand the Bragg peak of a particle beam.

15. The particle therapy system according to claim 1, further comprising: a track on which the collimator is mounted for movement; as well as A motor is configured to move the collimator along the track in response to one or more commands from the control system.

16. The particle therapy system of claim 1, wherein the plurality of openings comprises an array of holes.

17. The particle therapy system of claim 1, wherein the plurality of openings comprises a single linear array of holes.

18. The particle therapy system according to claim 1, wherein: The plurality of openings includes one or more slots extending through a longitudinal dimension of the collimator.

19. The particle therapy system according to claim 1, wherein: The one opening comprises a single slot extending through the longitudinal dimension of the collimator.

20. The particle therapy system according to claim 1, wherein: The collimator includes at least one of nickel, brass, or tungsten.

21. The particle therapy system of claim 12, wherein the collimator is a first collimator, wherein the particle therapy system comprises a second collimator, the second collimator comprising one or more openings, wherein the second collimator comprises a material that inhibits particle beam transport, and wherein the second collimator is mounted for movement within a beam field of the particle beam.

22. The particle therapy system according to claim 21, wherein: A motor is configured to move the second collimator along the track based on movement of the particle beam.

23. The particle therapy system of claim 21, wherein the first collimator and the second collimator are physically connected to each other.

24. The particle therapy system of claim 21, wherein the first collimator and the second collimator are configured to move independently relative to each other.

25. The particle therapy system of claim 21, wherein the motor is a first motor, and wherein the second collimator further comprises a second motor configured to move the second collimator.

26. The particle therapy system of claim 25, wherein the second motor is configured to move the second collimator based on movement of the particle beam.

27. A particle therapy system comprising: particle accelerators, used to generate particle beams to treat patients; a collimator including an opening, the collimator including a material that inhibits particle beam delivery and located between a particle accelerator and a patient, the opening shaping the particle beam in a manner that allows a portion of the particle beam to pass through the opening to reach a target within the patient; a plurality of structures, each of the plurality of structures being configured to change the energy of the particle beam as the particle beam passes through the structure, each of the plurality of structures comprising boron carbide; and; a control system configured to control movement of one or more of the plurality of structures into or out of a beam field of the particle beam to treat a depth of each column in the microvolume, thereafter advancing treatment to a next depth of each column in the microvolume until all columns in the microvolume are treated, the control system configured to control movement of the particle beam toward a first portion of an opening to enable at least a portion of the particle beam to reach the microvolume at a first energy, to control movement of the particle beam from the first portion of the opening to a second portion of the opening to enable at least a portion of the particle beam to reach the microvolume at the first energy, to control movement of the particle beam toward the first portion of the opening to enable at least a portion of the particle beam to reach the microvolume at a second energy, and to control movement of the particle beam toward the second portion of the opening to enable at least a portion of the particle beam to reach the microvolume of a patient at the second energy; Wherein, at each portion of the opening, the particle beam delivers a radiation dose to the target at an ultra-high dose rate.

28. The particle therapy system of claim 27, wherein the opening is a slot extending along the collimator.

29. The particle therapy system of claim 27, wherein: The control system is configured to control movement of the particle beam from the second portion of the opening to a plurality of additional portions of the opening.

30. The particle therapy system of claim 27, wherein: The particle beam delivers a radiation dose of more than 1 Gray per second to the target for less than 5 seconds.

31. The particle therapy system of claim 27, wherein: The particle beam delivers a radiation dose of 20 Gray per second to 100 Gray per second to the target for a duration of 10 milliseconds to 5 seconds.

32. The particle therapy system of claim 27, wherein: The particle beam delivers a radiation dose of 40 Gray per second to 120 Gray per second to the target for less than 5 seconds.

33. The particle therapy system of claim 27, wherein the particle beam treats a cylindrical portion of a target within a patient through the first portion of the opening.

34. The particle therapy system of claim 27, wherein the plurality of structures are part of a range adjuster between a particle accelerator and a patient.

35. The particle therapy system of claim 34, wherein the plurality of structures includes plates for varying the energy of the particle beam as it passes through one or more plates.

36. The particle therapy system of claim 27, wherein the particle accelerator comprises a superconducting magnet comprising conductive coils; and The control system is configured to vary the current through the conductive coil to vary the energy of the particle beam.

37. The particle therapy system of claim 27, further comprising: a track on which the collimator is mounted for movement within a beam field of the particle beam; and A motor is configured to move the collimator along the track.

38. The particle therapy system of claims 1 or 27, wherein the plurality of structures are part of a range adjuster comprising: an actuator, each actuator for controlling movement of a corresponding one of the plurality of structures into or out of a particle beam path; The range controller is located in a treatment room in which patients are treated with the particle beam.

39. The particle therapy system of claim 38, wherein each structure comprises a plate.

40. The particle therapy system of claim 38, wherein each structure comprises a polyhedron.

41. The particle therapy system of claim 38, wherein each structure is pure boron carbide.

42. The particle therapy system of claim 38, wherein one or more of the plurality of structures comprises a composite material consisting of boron carbide and graphite.

43. The particle therapy system of claim 38, wherein the range adjuster is positioned no further than 3 meters from the patient along the beamline of the particle beam.

44. The particle therapy system of claim 38, wherein: The range adjuster is positioned no further than 2 meters from the patient along the beamline of the particle beam.

45. The particle therapy system of claim 38, wherein: The range adjuster is positioned no further than 1 meter from the patient along the beamline of the particle beam.

46. ​​The particle therapy system of claim 38, further comprising: a scanning magnet for moving the particle beam relative to the patient; The range adjuster is located between the scanning magnet and the patient.

47. The particle therapy system of claim 38, wherein the particle beam is applied to the patient at a dose rate exceeding 1 Gray per second for a duration of less than 5 seconds.

48. The particle therapy system of claim 38, wherein the particle beam is applied to the patient at a dose rate of 20 Gray per second to 100 Gray per second for a duration of 10 milliseconds to 5 seconds.

49. The particle therapy system of claim 38, wherein the particle beam is applied to the patient at a dose rate of 40 Gray per second to 120 Gray per second for a duration of less than 5 seconds.

50. The particle therapy system of claim 38, wherein the actuator comprises a linear motor.

51. The particle therapy system of claims 1 or 27, wherein the plurality of structures are part of a range adjuster comprising: an actuator for controlling the plurality of structures to move into or out of a particle beam path; The range adjuster is positioned along the beam line of the particle beam so that it is no more than 4 meters away from the patient.

52. The particle therapy system of claim 51, wherein the range adjuster is positioned no further than 3 meters from the patient along the beamline of the particle beam.

53. The particle therapy system of claim 51, wherein: The range adjuster is positioned no further than 2 meters from the patient along the beamline of the particle beam.

54. The particle therapy system of claim 51, wherein: The range adjuster is positioned no further than 1 meter from the patient along the beamline of the particle beam.

55. The particle therapy system of claim 51 , wherein the particle beam is applied to the patient at a dose rate exceeding 1 Gray per second for a duration of less than 5 seconds.

56. The particle therapy system of claim 51 , wherein the particle beam is applied to the patient at a dose rate of 20 Gray per second to 100 Gray per second for a duration of 10 milliseconds to 5 seconds.

57. The particle therapy system of claim 51 , wherein the particle beam is applied to the patient at a dose rate of 40 Gray per second to 120 Gray per second for a duration of less than 5 seconds.

58. The particle therapy system of claim 51 , wherein the actuator comprises a linear motor.

59. The particle therapy system of claim 51 , wherein one or more of the plurality of structures comprises a composite material consisting of boron carbide and graphite.

60. The particle therapy system of claim 1 or 27, comprising: a scanning magnet for moving the particle beam relative to the patient; and Wherein, the plurality of structures are part of a range regulator, the range regulator comprising: an actuator, each actuator for controlling movement of a corresponding one of the plurality of structures into or out of a particle beam path; The range adjuster is located between the scanning magnet and the patient.

61. The particle therapy system of claim 60, wherein: The range adjuster is positioned no further than 1 meter from the patient along the beamline of the particle beam.

62. The particle therapy system of claim 60, wherein the particle beam is applied to the patient at a dose rate exceeding 1 Gray per second for a duration of less than 5 seconds.

63. The particle therapy system of claim 60, wherein the particle beam is applied to the patient at a dose rate of 20 Gray per second to 100 Gray per second for a duration of 10 milliseconds to 5 seconds.

64. The particle therapy system of claim 60, wherein the particle beam is applied to the patient at a dose rate of 40 Gray per second to 120 Gray per second for a duration of less than 5 seconds.

65. The particle therapy system of claim 60, further comprising: An external gantry on which the particle accelerator is mounted, the external gantry being controllable to move the particle accelerator at least partially around the patient.

66. The particle therapy system of claim 65, further comprising: An inner gantry is controllable to move in unison with the outer gantry, the inner gantry including a nozzle extendable toward and retractable away from the patient, the range adjuster being located in the nozzle.

67. The particle therapy system of claim 66, wherein: The range adjuster is located in a treatment room where the particle beam is applied to a patient; and The nozzle can be completely retracted into the internal platform.

68. The particle therapy system of claim 60, wherein the particle beam has a beam spot size of less than 1.2 centimeters (cm) sigma for a particle beam having an energy of 70 MeV or greater.

69. The particle therapy system of claim 60, wherein the particle beam has a beam spot size of less than 1.2 centimeters (cm) sigma.

70. The particle therapy system of claim 60, wherein the particle beam has a beam spot size of less than 0.5 centimeters (cm) sigma.

71. The particle therapy system of claim 60, wherein there is no structure for affecting the particle beam between the range adjuster and the patient.

72. The particle therapy system of claim 60, wherein: The collimator is between the range adjuster and the patient.

73. The particle therapy system of claim 60, wherein the actuator comprises a linear motor.

74. The particle therapy system of claim 60, wherein the actuators include rotary motors, each rotary motor driving a corresponding linear actuator to control movement of a corresponding structure.

75. The particle therapy system of claim 60, wherein one or more of the plurality of structures comprises a composite material consisting of boron carbide and graphite.

76. The particle therapy system of claim 60, wherein each of said plurality of structures comprises pure boron carbide.

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