Mitsubishi Electric Corporation

Mitsubishi Denki Kabushiki Kaisha

Hitachi, Ltd.

Yuehu Pu

Taizo Honda

Hisashi Harada

Masahiro Ikeda

Takaaki Iwata

Yuichi Yamamoto

Toshihiro Otani

Kazushi Hanakawa

Hidenobu Sakamoto

Tadashi Katayose

Yukiko Yamada

Osamu Takahashi

Yusuke Sakamoto

Kazuo Yamamoto

Hiroshi Otani

Hirofumi Tanaka

Kanji Shinkawa

Katsuhisa Yoshida

Nobuyuki Haruna

Nobuhiko Ina

Yasuyuki Takatani

Takayuki Kashima

Shinya Tajiri

Haruo Yamashita

In a particle beam irradiation apparatus that controls a scanning apparatus so that each irradiation position is irradiated with a particle beam a rescan-count number of times by repeating for the rescan-count number of times the irradiation of all irradiation positions in the irradiation target, the irradiation apparatus includes a calculator that receives either one of a rescan count n or a beam intensity J that is a particle beam dose per unit time, to calculate a maximum value of the other satisfying the following conditional expression (P1) for all irradiation positions to present the maximum value to a user.&#x2003;&#x2003;(P1)

Particle beam irradiation apparatus

A particle beam irradiation apparatus radiates a particle beam plural times per one irradiation position. A storage unit stores a dose to be radiated each of the times (divisional target dose). A dose monitor measures the dose of the particle beam radiated to the irradiation position. At the first time of radiation, a controller outputs an interruption signal when the dose measured by the dose monitor reaches the divisional target dose. The dose monitor measures a dose (excessive dose) radiated after the interruption signal is outputted until the particle beam is actually interrupted. Then, it is defined: Corrected Dose value=Divisional Target Dose&#x2212;Excessive Dose Value. Instead, it may be defined: Corrected Dose value=Divisional Target Dose&#x2212;Excessive Dose Estimation Value. At the second time of radiation, the controller outputs an interruption signal when the dose measured by the dose monitor reaches the corrected dose value.

An irradiation apparatus radiates a particle beam after forming the beam for plural layers. A dose monitor measures a dose in real time. A dose evaluation unit evaluates an irradiation dose for each layer on the basis of a value measured by the dose monitor and a dose calibration factor set for each layer. An irradiation control section performs radiation control for each layer on the basis of an evaluation result of the dose evaluation unit. An interpolation value generation unit uses actual-measurement dose-calibration factors obtained by radiating a particle beam to a simulated phantom provided with a calibration dosimeter, to generate an interpolation estimation value of the dose calibration factor. For each layer subject to the interpolation value, and based on an irradiation condition of that layer, the interpolation value generation unit performs weighting on each of the actual-measurement dose-calibration factors.

Particle therapy device and method for setting dose calibration factor

In the particle beam therapy system, a beam transport system includes a beam-path changer for changing a beam path so as to transport a charged particle beam to any one of the plurality of particle beam irradiation apparatuses; and a treatment management device includes a beam-path controller that generates an emitter control signal for controlling an emitter of an accelerator and a beam-path changer control signal for controlling the beam-path changer so that, with respect to the plurality of particle beam irradiation apparatuses in which treatment is performed at the same treatment period of time, the charged particle beam is transported to each one of the plurality of particle beam irradiation apparatuses for each time period allocated thereto.

Particle beam therapy system

A particle beam scanning irradiation system includes a computer establishing a scanning sequence for irradiation of a tumor portion in a patient; and a particle beam irradiation device irradiating the tumor portion in accordance with the established scanning sequence of the particle beam. The computer selects all conceivable combinations of pairs of irradiation spots among the plurality of irradiation spots arranged in the tumor portion, and determines whether each path for the particle beam to shift between two spots constituting the selected pair passes through the tumor portion; determines a penalty matrix expressing whether each path passes through the tumor portion on the basis of the determination result; evaluates a function for the shift paths on the basis of an optimizing algorithm, and establishes the scanning sequence of the particle beam by an optimized solution of the function.

Particle beam scanning irradiation system

A beam data processing apparatus has a plurality of channel data conversion units that convert a plurality of analogue signals outputted from a position monitor into digital signals, a position size processing unit that calculates a beam position, based on voltage information items obtained through processing by the plurality of channel data conversion units, an abnormality determination processing unit that determines the beam position and generates a position abnormality signal, and an integrated control unit that controls the plurality of channel data conversion units in such a way that while a beam is stopped at an irradiation spot, digital signal conversion processing is implemented two or more times; the channel data conversion unit has a plurality of A/D converters, a demultiplexer that distributes analogue signals, and a multiplexer that switches respective digital signals processed by the A/D converters so as to output them to the position size processing unit.

Beam data processing apparatus and particle beam therapy system

A particle beam irradiation apparatus according to the present invention is provided with a vacuum duct that forms a vacuum region through which the charged particle beam passes, a vacuum window through which the charged particle beam is launched from the vacuum region, a scanning electromagnet that scans the charged particle beam; a monitoring apparatus including a position monitor that detects the passing position of a charged particle beam and the beam size thereof, a low-scattering gas filling chamber including the monitoring apparatus, and an irradiation management apparatus that controls irradiation of the charged particle beam; the particle beam irradiation apparatus is characterized in that the low-scattering gas filling chamber is changeably disposed in such a manner that the beam-axis-direction positional relationship between the monitoring apparatus and the vacuum window is a desired one and in that the low-scattering gas filling chamber is filled with a low-scattering gas.

Particle beam irradiation apparatus having adjustable low-scattering filling chamber and particle beam therapy system

A particle beam scanning irradiation method includes the steps of calculating a planned irradiating particle count of a particle beam for each of irradiation spots, on the basis of a relative amount of particle beam irradiation and a prescription particle-beam dose determined from a particle-beam therapy plan; simulating an irradiation process of the particle beam at each irradiation spot, on the basis of the planned irradiating particle count and a beam current waveform of the particle beam, and calculating a particle count of the particle beam irradiating the diseased portion during a scan shift of the particle beam; correcting the planned irradiating particle count for each irradiation spot by using the irradiating particle count during the scan shift; converting the corrected planned-irradiation particle count into a count value used in a dose monitor; and irradiating the irradiation spot with the particle beam, on the basis of the converted count value.

A particle beam therapy system comprising a treatment table, a treatment table control unit and an irradiation control unit configured to output an instruction for controlling the treatment table control unit, an accelerator and a scanning electromagnet, wherein after the treatment table control unit controls the treatment table so as for a patient isocenter which is reference position of an affected area of a patient to move to a position of an irradiation isocenter which is set at a position which is closer to an irradiation nozzle than an equipment isocenter which is reference of positional relation of the irradiation nozzle and the treatment table, the irradiation control unit outputs an instruction for irradiating the patient with a particle beam.

There is provided a particle-beam energy changing apparatus that is capable of changing energy of a particle beam quickly and silently, in which a first energy changing unit and a second energy changing unit for changing energy of a particle beam passing therethrough by varying thicknesses of their attenuators attenuating the particle beam energy are arranged so that the particle beam passes through the first energy changing unit and the second energy changing unit; and the maximum attenuation amount by the first energy changing unit is set smaller than the maximum attenuation amount by the second energy changing unit.

Particle-beam energy changing apparatus, particle beam therapy system including the same, and method of changing particle beam energy

In order to obtain a particle beam irradiation apparatus that enlarges the dose distribution of beam spots while suppressing a decrease of the maximum available range of a charged particle beam, the particle beam irradiation apparatus includes a particle beam acceleration means; particle beam transport means; scanning apparatus that includes first scanning means and second scanning means, and two-dimensionally scans the beam; and irradiation control means that controls the scanning apparatus so as to irradiate the beam onto a target region including a plurality of small regions. The irradiation control means controls the first scanning means so as to scan the beam over a small region serving as an irradiation subject among the plurality of the small regions, and controls the second scanning means so as to change the small region serving as the irradiation subject to be a different small region among the plurality of the small regions.

Particle beam irradiation apparatus utilized in medical field

A charged particle beam position monitor is provided with a plurality of position monitors and a beam data processing device that performs calculation processing of the state of a charged particle beam, based on a plurality of signals outputted from the position monitors. The beam data processing device includes a plurality of channel data conversion units that perform AD conversion processing of the plurality of signals outputted from the position monitors; a position size processing unit, for each of the position monitors, that calculates the beam position of the beam, based on voltage information obtained through the AD conversion processing; and an integrated control unit that controls the plurality of channel data conversion units in such a way that while the beam is irradiated onto an irradiation subject, AD conversion processing of the signals is performed at different timings for the respective position monitors.

Beam position monitor and particle beam therapy system

A particle beam irradiation apparatus comprises a particle beam shielding member which shields a part of a particle beam which is scanned, a prompt signal detector which detects a prompt signal which is generated when the particle beam which is scanned collides with the particle beam shielding member and a signal comparison device which predicts and obtains a generation pattern of a prompt signal which is generated with a predetermined scanning pattern and stores as a signal time pattern for comparison, wherein the signal comparison device detects an abnormality of scanning of a particle beam or the particle beam shielding member by comparing a detected signal time pattern which is a time pattern of a signal which is detected by the prompt signal detector to a signal time pattern for comparison which is stored.

Particle beam irradiation apparatus and particle beam therapy system

The circular accelerator comprises: a bending electromagnet that generates a bending magnetic field; a radio-frequency power source that generates a radio-frequency electric field in accordance with an orbital frequency of charged particles; a radio-frequency electromagnetic field coupling part connected to the radio-frequency power source; an acceleration electrode connected to the radio-frequency electromagnetic field coupling part; and an acceleration-electrode-opposing ground plate provided to form an acceleration gap between the plate itself and the acceleration electrode, for generating the radio-frequency electromagnetic field in an orbiting direction of the charged particles; wherein the bending electromagnet generates the bending magnetic field varying in such a way that the orbital frequency of the charged particles varies in a variation range of 0.7% to 24.7% with respect to an orbital frequency at the charged-particles' extraction portion, during a time of injection to extraction of the particles.

Circular accelerator and operating method therefor

A particle beam irradiation system comprising a first deflector having the maximum deflection amount which enables to move a particle beam in one direction to the maximum width of a target and a second deflector having the maximum deflection amount is less than the maximum deflection amount of the first deflector performs a control in which the particle beam is moved by increasing at least a deflection amount of the second deflector when the particle beam is moved, and performs a deflection substitution control in which a deflection of the second deflector is substituted to a deflection of the first deflector by decreasing the deflection amount of the second deflector and changing a deflection amount of the first deflector so as to make a position of the particle beam in the target dwell when the particle beam dwells.

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Tokyo, Japan

Yuehu Pu