A5049562896- Radiation Therapy and Dosimetry
- Advanced Radiotherapy Techniques
- Radiation Detection and Scintillator Technologies
- Radiation Effects in Electronics
- Nuclear Physics and Applications
- Medical Imaging Techniques and Applications
- Particle accelerators and beam dynamics
- Effects of Radiation Exposure
- Boron Compounds in Chemistry
- Particle Detector Development and Performance
- Radiation Effects and Dosimetry
- Advanced X-ray and CT Imaging
- Graphite, nuclear technology, radiation studies
- Ion-surface interactions and analysis
- Atomic and Subatomic Physics Research
- Integrated Circuits and Semiconductor Failure Analysis
- DNA Repair Mechanisms
- Muon and positron interactions and applications
- Electromagnetic Fields and Biological Effects
- Cancer, Hypoxia, and Metabolism
- Radiopharmaceutical Chemistry and Applications
- Prostate Cancer Diagnosis and Treatment
- Mass Spectrometry Techniques and Applications
- Electron and X-Ray Spectroscopy Techniques
- X-ray Spectroscopy and Fluorescence Analysis
National Institutes for Quantum Science and Technology
2016-2025
Osaka University
2022-2024
National Institute of Health Sciences
2014
Institute of Particle Physics
2013
Motion Control (United States)
2013
TCL (China)
2009
Tokyo Institute of Technology
2003-2008
We describe a method to calculate the relative biological effectiveness in mixed radiation fields of therapeutic ion beams based on modified microdosimetric kinetic model (modified MKM). In addition, we show procedure for integrating MKM into treatment planning system scanned carbon beam. With this procedure, is fully integrated our research version system. To account change radiosensitivity cell line, measured one three parameters from single survival curve current cells and used parameter...
At the National Institute of Radiological Sciences (NIRS), more than 8,000 patients have been treated for various tumors with carbon-ion (C-ion) radiotherapy in past 20 years based on a radiobiologically defined clinical-dose system. Through clinical experience, including extensive dose escalation studies, optimum dose-fractionation protocols established respective tumors, which may be considered as standards C-ion radiotherapy. Although therapeutic appropriateness system has widely...
Purpose: A project to construct a new treatment facility, as an extension of the existing HIMAC has been initiated for further development carbon‐ion therapy at NIRS. This facility is equipped with 3D irradiation system pencil‐beam scanning. The challenge this realize moving target by scanning irradiation. To achieve fast rescanning within acceptable time, authors developed system. Methods: In order verify validity design and demonstrate performance prior use in scanning‐irradiation was...
The biological effect of charged-particle beams depends on both dose and particle spectrum. As one the physical quantities describing spectrum beams, we considered linear energy transfer (LET) throughout this study. We investigated a new therapeutic technique using two or more ion species in treatment session, which call an intensity modulated composite therapy (IMPACT), for optimizing dose-averaged LET distributions patient as its proof principle. Protons helium, carbon, oxygen ions were...
Purpose: In moving target irradiation with pencil beam scanning, the interplay effect between motion and scanned is a problem because this causes over or under dosage in volume. To overcome this, we have studied rescanning using gating technique. Methods: A simulation experimental study was carried out. experiment, used fast scanning system developed at HIMAC to verify validity of phase controlled method, which time for each slice matched duration. Results: Simulation results showed that...
The OpenPET geometry is our new idea to visualize a physically opened space between two detector rings. In this paper, we developed the first small prototype show proof-of-concept of imaging. Two rings 110 mm diameter and 42 axial length were placed with gap mm. basic imaging performance was confirmed through phantom studies; open realized at cost slight loss resolution 24% sensitivity. For PET image-guided radiation therapy, carried out in-beam tests 11C radioactive beam irradiation in...
The long patient port of a PET scanner tends to put stress on patients, especially patients with claustrophobia. It also prevents doctors and technicians from taking care during scanning. In this paper, we proposed an 'open PET' geometry, which consists two axially separated detector rings. A continuous field-of-view (FOV) including 360° opened gap between rings can be imaged enabling fully 3D image reconstruction all the possible lines-of-response. open will become practical if iterative...
A project to construct a new treatment facility as an extension of the existing heavy-ion medical accelerator in chiba (HIMAC) has been initiated for further development carbon-ion therapy. The greatest challenge this is realize moving target by scanning irradiation. For purpose, we decided combine rescanning technique and gated irradiation method. To determine how avoid hot and/or cold spots relatively large number rescannings within acceptable time, have studied strategy, magnets their...
Abstract Ionising radiation induced DNA damage and subsequent biological responses to it depend on the radiation’s track-structure its energy loss distribution pattern. To investigate underlying mechanisms involved in such complex system, there is need of predicting response by integrated Monte Carlo (MC) simulations across physics, chemistry biology. Hence, this work, we have developed an application using open source Geant4-DNA toolkit propose a realistic “fully integrated” MC simulation...
Our understanding of radiation induced cellular damage has greatly improved over the past decades. Despite this progress, there are still many obstacles to fully how interacts with biologically relevant components form observable endpoints. One hurdle is difficulty faced by members different research groups in directly comparing results. Multiple Monte Carlo codes have been developed simulate induction at DNA scale, while same time various models that describe repair processes varying levels...
This feasibility study confirmed the initial safety and efficacy of a novel carbon-ion radiotherapy (CIRT) using linear energy transfer (LET) painting for head neck cancer. is first step toward establishing CIRT with LET in clinical practice making it standard future.
Washout of 10C and 11C implanted by radioactive beams in brain thigh muscle rabbits was studied. The biological washout effect a living body is important the range verification system or three-dimensional volume imaging heavy ion therapy. Positron emitter were rabbit annihilation gamma-rays measured an situ positron camera which consisted pair scintillation cameras set on either side target. ROI (region interest) as two-dimensional position distribution time–activity curve measured....
Purpose: In radiotherapy with a scanned carbon‐ion beam, its Bragg peak is shifted along the depth direction either by inserting range shifter plates or changing beam‐extraction energy of synchrotron. former technique (range scanning: RS), broaden beam size and produce secondary fragments through nuclear reactions. latter (active‐energy ES), it may take several seconds to change depending on synchrotron operation cycle, leading long treatment time. The authors propose hybrid scan (hybrid...
Treatment plans of carbon-ion radiotherapy have been made on the assumption that beams are delivered instantaneously irrespective to dose delivery time as well interruption time. The advanced therapeutic techniques such a hypofractionation and respiratory gating usually require more deliver fractioned than conventional techniques. purpose this study was investigate effects dose-delivery structure biological effectiveness in radiotherapy. rate equations defined microdosimetric kinetic model...
Challenging issues in treatment planning for scanned carbon-ion (C-ion) therapy are (i) accurate calculation of dose distribution, including the contribution large angle-scattered fragments, (ii) reduction memory space required to store kernel individual pencil beams and (iii) shortening computation time optimization calculation. To calculate from we modeled transverse profile C-ion beam with superposition three Gaussian distributions. The development belonging first component was calculated...
The microdosimetric kinetic (MK) model underestimates the cell-survival fractions for high linear energy transfer (LET) and dose irradiations. To address issue, some researchers previously extended MK to stochastic (SMK) model. In SMK model, radiation induced were estimated from specific energies z d n absorbed by a microscopic subnuclear structure domain cell nucleus, respectively. By taking nature of as well that into account, could reproduce measured radiations with wide LET ranges....
The single-ring OpenPET (SROP), for which the detector arrangement has a cylinder shape cut by two parallel planes at slant angle to form an open space, is our original proposal in-beam PET. In this study, we developed small prototype of axial-shift type SROP (AS-SROP) with novel transformable architecture proof-of-concept. AS-SROP, detectors originally forming cylindrical PET are axially shifted little little. We designed AS-SROP 4-layer depth-of-interaction arranged in ring diameter 250...
Abstract Imaging of nuclear gamma-ray lines in the 1–10 MeV range is far from being established both medical and physical applications. In proton therapy, 4.4 gamma rays are emitted excited nucleus either 12 C* or 11 B* considered good indicators dose delivery and/or verification. Further, astronomy, produced by cosmic ray interactions interstellar medium, can thus be used to probe nucleothynthesis universe. this paper, we present a high-precision image taken newly developed 3-D position...
Research into high linear energy transfer (LET) radiotherapy now spans over half a century, beginning with helium and deuteron treatment in 1952 today ranging from fast neutrons to carbon-ions. Owing pioneering work initially the United States thereafter Germany Japan, increasing focus is on carbon-ion beam: 12 centers are operation, five under construction three planning. While beam has demonstrated unique promising suitability laboratory clinical trials toward hypofractionated of hypoxic...
Dose-averaged linear energy transfer (LETd) is one of the important factors in determining clinical outcomes for carbon-ion radiation therapy. Innovative LET painting (LP) has been developed as an advanced form conventional intensity modulated therapy (IMIT) at QST Hospital. The study had 2 motivations: to increase minimum LETd (LETdmin) and improve uniformity distribution within gross tumor volume (GTV) by using LP treatment plans patients with head neck cancer while maintaining relative...
The latest heavy ion therapy tends to require information about the spatial distribution of quality radiation in a patient's body order make best use any potential advantage swift ions for therapeutic treatment tumour. deflection incident particles is described well by Molière's multiple-scattering theory primary particles; however, projectile fragments not yet thoroughly understood. This paper reports on our investigation produced from carbon beam through nuclear reactions thick water. A...
In scanned carbon-ion (C-ion) radiotherapy, some primary C-ions undergo nuclear reactions before reaching the target and resulting particles deliver doses to regions at a significant distance from central axis of beam. The effects these on physical dose distribution are accounted for in treatment planning by representing transverse profile C-ion beam as superposition three Gaussian distributions. calculation biological distribution, however, radiation quality has been assumed be uniform over...