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Kavitaa Nedunchezhian, Nalini Aswath, Manigandan Thiruppathy, Sarumathi Thirugnanamurthy
Boron Neutron Capture Therapy (BNCT) is a radiation science which is emerging as a hopeful tool in treating cancer, by selectively concentrating boron compounds in tumour cells and then subjecting the tumour cells to epithermal neutron beam radiation. BNCT bestows upon the nuclear reaction that occurs when Boron-10, a stable isotope, is irradiated with low-energy thermal neutrons to yield α particles (Helium-4) and recoiling lithium-7 nuclei. A large number of 10 Boron (10B) atoms have to be localized on or within neoplastic cells for BNCT to be effective, and an adequate number of thermal neutrons have to be absorbed by the 10B atoms to maintain a lethal 10B (n, α) lithium-7 reaction...
December 2016: Journal of Clinical and Diagnostic Research: JCDR
Mindy Hsieh, Yingzi Liu, Farshad Mostafaei, Jean M Poulson, Linda H Nie
PURPOSE: Boron neutron capture therapy (BNCT) is a binary treatment modality that uses high LET particles to achieve tumor cell killing. Deuterium-deuterium (DD) compact neutron generators have advantages over nuclear reactors and large accelerators as the BNCT neutron source, such as their compact size, low cost, and relatively easy installation. The purpose of this study is to design a beam shaping assembly (BSA) for a DD neutron generator and assess the potential of a DD-based BNCT system using Monte Carlo (MC) simulations...
February 2017: Medical Physics
Nicolas Arbor, Stephane Higueret, Halima Elazhar, Rodolphe Combe, Philippe Meyer, Nicolas Dehaynin, Florence Taupin, Daniel Husson
The peripheral dose distribution is a growing concern for the improvement of new external radiation modalities. Secondary particles, especially photo-neutrons produced by the accelerator, irradiate the patient more than tens of centimeters away from the tumor volume. However the out-of-field dose is still not estimated accurately by the treatment planning softwares. This study demonstrates the possibility of using a specially designed CMOS sensor for fast and thermal neutron monitoring in radiotherapy. The 14 microns-thick sensitive layer and the integrated electronic chain of the CMOS are particularly suitable for real-time measurements in γ/n mixed fields...
March 7, 2017: Physics in Medicine and Biology
Yongqiang Li, Wen Hsi
To analyze measurement deviations of patient-specific quality assurance (QA) using intensity-modulated spot-scanning particle beams, a commercial radiation dosimeter using 24 pin-point ionization chambers was utilized. Before clinical trial, the validations of radiation dosimeter as well as treatment planning system were executed. During clinical trial 165 measurements were performed on 36 patients enrolled. Two or three fields were used for each patient. Measurements were typically performed with the dosimeter placed at special regions of dose distribution along depth and lateral profiles...
February 3, 2017: Physics in Medicine and Biology
Mitsutaka Yamaguchi, Yuto Nagao, Takahiro Satoh, Hiroyuki Sugai, Makoto Sakai, Kazuo Arakawa, Naoki Kawachi
The purpose of this study is to determine whether the main component of the low-energy (63-68 keV) particles emitted perpendicularly to the (12)C beam from the (12)C-irradiated region in a water phantom is secondary electron bremsstrahlung (SEB). Monte Carlo simulations of a (12)C-beam (290 MeV/u) irradiated on a water phantom were performed. A detector was placed beside the water phantom with a lead collimator between the phantom and the detector. To move the Bragg-peak position, a binary filter was placed in an upper stream of the phantom...
January 2017: Review of Scientific Instruments
Toke Printz Ringbæk, Yuri Simeonov, Matthias Witt, Rita Engenhart-Cabillic, Gerhard Kraft, Klemens Zink, Uli Weber
Porous materials with microscopic structures like foam, sponges, lung tissues and lung substitute materials have particular characteristics, which differ from those of solid materials. Ion beams passing through porous materials show much stronger energy straggling than expected for non-porous solid materials of the same thickness. This effect depends on the microscopic structure, the density and the thickness of the porous material. The beam-modulating effect from a porous plate enlarges the Bragg peak, yielding similar benefits in irradiation time reduction as a ripple filter...
January 31, 2017: Physics in Medicine and Biology
Nan Qin, Marco Pinto, Zhen Tian, Georgios Dedes, Arnold Pompos, Steve Jiang, Katia Parodi, Xun Jia
Monte Carlo (MC) simulation is considered as the most accurate method for calculation of absorbed dose and fundamental physics quantities related to biological effects in carbon ion therapy. To improve its computational efficiency, we have developed a GPU-oriented fast MC package named goCMC, for carbon therapy. goCMC simulates particle transport in voxelized geometry with kinetic energy up to 450 MeV/u. Class II condensed history simulation scheme with a continuous slowing down approximation was employed. Energy straggling and multiple scattering were modeled...
January 31, 2017: Physics in Medicine and Biology
Giovanna Muggiolu, Michal Pomorski, Gérard Claverie, Guillaume Berthet, Christine Mer-Calfati, Samuel Saada, Guillaume Devès, Marina Simon, Hervé Seznec, Philippe Barberet
As well as being a significant source of environmental radiation exposure, α-particles are increasingly considered for use in targeted radiation therapy. A better understanding of α-particle induced damage at the DNA scale can be achieved by following their tracks in real-time in targeted living cells. Focused α-particle microbeams can facilitate this but, due to their low energy (up to a few MeV) and limited range, α-particles detection, delivery, and follow-up observations of radiation-induced damage remain difficult...
January 31, 2017: Scientific Reports
M Rovituso, C Schuy, U Weber, S Brons, M A Cortés-Giraldo, C La Tessa, E Piasetzky, D Izraeli, D Schardt, M Toppi, E Scifoni, M Krämer, M Durante
Recently, the use of (4)He particles in cancer radiotherapy has been reconsidered as they potentially represent a good compromise between protons and (12)C ions. The first step to achieve this goal is the development of a dedicated treatment planning system, for which basic physics information such as the characterization of the beam lateral scattering and fragmentation cross sections are required. In the present work, the attenuation of (4)He primary particles and the build-up of secondary charged fragments at various depths in water and polymethyl methacrylate were investigated experimentally for 120 and 200 MeV u(-1) beams delivered by the synchrotron at the Heidelberg Ion-Beam Therapy Center, Heidelberg...
February 21, 2017: Physics in Medicine and Biology
M Marafini, R Paramatti, D Pinci, G Battistoni, F Collamati, E De Lucia, R Faccini, P M Frallicciardi, C Mancini-Terracciano, I Mattei, S Muraro, L Piersanti, M Rovituso, A Rucinski, A Russomando, A Sarti, A Sciubba, E Solfaroli Camillocci, M Toppi, G Traini, C Voena, V Patera
Nowadays there is a growing interest in particle therapy treatments exploiting light ion beams against tumors due to their enhanced relative biological effectiveness and high space selectivity. In particular promising results are obtained by the use of (4)He projectiles. Unlike the treatments performed using protons, the beam ions can undergo a fragmentation process when interacting with the atomic nuclei in the patient body. In this paper the results of measurements performed at the Heidelberg Ion-Beam Therapy center are reported...
February 21, 2017: Physics in Medicine and Biology
I Mattei, F Bini, F Collamati, E De Lucia, P M Frallicciardi, E Iarocci, C Mancini-Terracciano, M Marafini, S Muraro, R Paramatti, V Patera, L Piersanti, D Pinci, A Rucinski, A Russomando, A Sarti, A Sciubba, E Solfaroli Camillocci, M Toppi, G Traini, C Voena, G Battistoni
Charged particle beams are used in particle therapy (PT) to treat oncological patients due to their selective dose deposition in tissues with respect to the photons and electrons used in conventional radiotherapy. Heavy (Z  >  1) PT beams can additionally be exploited for their high biological effectiveness in killing cancer cells. Nowadays, protons and carbon ions are used in PT clinical routines. Recently, interest in the potential application of helium and oxygen beams has been growing. With respect to protons, such beams are characterized by their reduced multiple scattering inside the body, increased linear energy transfer, relative biological effectiveness and oxygen enhancement ratio...
February 21, 2017: Physics in Medicine and Biology
Oliver Rubel, Burlen Loring, Jean-Luc Vay, David P Grote, Remi Lehe, Stepan Bulanov, Henri Vincenti, E Wes Bethel
The generation of short pulses of ion beams through the interaction of an intense laser with a plasma sheath offers the possibility of compact and cheaper ion sources for many applications--from fast ignition and radiography of dense targets to hadron therapy and injection into conventional accelerators. To enable the efficient analysis of large-scale, high-fidelity particle accelerator simulations using the Warp simulation suite, the authors introduce the Warp In situ Visualization Toolkit (WarpIV). WarpIV integrates state-of-the-art in situ visualization and analysis using VisIt with Warp, supports management and control of complex in situ visualization and analysis workflows, and implements integrated analytics to facilitate query- and feature-based data analytics and efficient large-scale data analysis...
May 2016: IEEE Computer Graphics and Applications
Giacomo Traini, Giuseppe Battistoni, Angela Bollella, Francesco Collamati, Erika De Lucia, Riccardo Faccini, Fernando Ferroni, Paola Maria Frallicciardi, Carlo Mancini-Terracciano, Michela Marafini, Ilaria Mattei, Federico Miraglia, Silvia Muraro, Riccardo Paramatti, Luca Piersanti, Davide Pinci, Antoni Rucinski, Andrea Russomando, Alessio Sarti, Adalberto Sciubba, Martina Senzacqua, Elena Solfaroli-Camillocci, Marco Toppi, Cecilia Voena, Vincenzo Patera
Charged particle therapy is a technique for cancer treatment that exploits hadron beams, mostly protons and carbon ions. A critical issue is the monitoring of the beam range so to check the correct dose deposition to the tumor and surrounding tissues. The design of a new tracking device for beam range real-time monitoring in pencil beam carbon ion therapy is presented. The proposed device tracks secondary charged particles produced by beam interactions in the patient tissue and exploits the correlation of the charged particle emission profile with the spatial dose deposition and the Bragg peak position...
January 19, 2017: Physica Medica: PM
Valentina Giacometti, Vladimir A Bashkirov, Pierluigi Piersimoni, Susanna Guatelli, Tia E Plautz, Hartmut F-W Sadrozinski, Robert P Johnson, Andriy Zatserklyaniy, Thomas Tessonnier, Katia Parodi, Anatoly B Rosenfeld, Reinhard W Schulte
PURPOSE: Proton computed tomography (pCT) is a promising imaging technique to substitute or at least complement x-ray CT for more accurate proton therapy treatment planning as it allows calculating directly proton relative stopping power from proton energy loss measurements. A proton CT scanner with a silicon-based particle tracking system and a 5 stage scintillating energy detector has been completed. In parallel a modular software platform was developed to characterize the performance of the proposed pCT...
January 17, 2017: Medical Physics
Sebastian Meyer, Chiara Gianoli, Lorena Magallanes, Benedikt Kopp, Thomas Tessonnier, Guillaume Landry, George Dedes, Bernd Voss, Katia Parodi
Ion beam therapy offers the possibility of a highly conformal tumor-dose distribution; however, this technique is extremely sensitive to inaccuracies in the treatment procedures. Ambiguities in the conversion of Hounsfield units of the treatment planning x-ray CT to relative stopping power (RSP) can cause uncertainties in the estimated ion range of up to several millimeters. Ion CT (iCT) represents a favorable solution allowing to directly assess the RSP. In this simulation study we investigate the performance of the integration-mode configuration for carbon iCT, in comparison with a single-particle approach under the same set-up...
February 7, 2017: Physics in Medicine and Biology
Hermann Fuchs, Philipp Moser, Martin Gröschl, Dietmar Georg
PURPOSE: To investigate and model effects of magnetic fields on proton and carbonion beams for dose calculation. METHODS: In a first step Monte Carlo simulations using Gate 7.1/Geant4.10.0.p03 were performed for proton and carbon ion beams in magnetic fields ranging from 0 to 3 T. Initial particle energies ranged from 60-250 MeV (protons) and 120-400 MeV/u (carbon ions), respectively. The resulting dose distributions were analyzed focusing on beam deflection, dose deformation as well as the impact of material het- erogeneities...
January 16, 2017: Medical Physics
Jie Yang, Pengcheng Zhang, Liyuan Zhang, Huazhong Shu, Baosheng Li, Zhiguo Gui
In inverse treatment planning of intensity-modulated radiation therapy (IMRT), the objective function is typically the sum of the weighted sub-scores, where the weights indicate the importance of the sub-scores. To obtain a high-quality treatment plan, the planner manually adjusts the objective weights using a trial-and-error procedure until an acceptable plan is reached. In this work, a new particle swarm optimization (PSO) method which can adjust the weighting factors automatically was investigated to overcome the requirement of manual adjustment, thereby reducing the workload of the human planner and contributing to the development of a fully automated planning process...
January 2017: Physica Medica: PM
M E Capoulat, A J Kreiner
PURPOSE: Boron Neutron Capture Therapy (BNCT) requires neutron sources suitable for in-hospital siting. Low-energy particle accelerators working in conjunction with a neutron producing reaction are the most appropriate choice for this purpose. One of the possible nuclear reactions is (13)C(d,n)(14)N. The aim of this work is to evaluate the therapeutic capabilities of the neutron beam produced by this reaction, through a 30mA beam of deuterons of 1.45MeV. METHODS: A Beam Shaping Assembly design was computationally optimized...
January 2017: Physica Medica: PM
M Chen, S Jiang, Y Shao, W Lu
PURPOSE: In-vivo range detection/verification is crucial in particle therapy for effective and safe delivery. The state-of-art techniques are not sufficient for in-vivo on-line range verification due to conflicts among patient dose, signal statistics and imaging time. We propose a novel intra-beam range detection and adaptation strategy for particle therapy. METHODS: This strategy uses the planned mid-range spots as probing beams without adding extra radiation to patients...
June 2016: Medical Physics
M Park, G Kim, H Jung, S Park, S Park, Y Ji, J Yun
PURPOSE: The purpose of this simulation study is to evaluate the proton detectability of gel dosimeters, and estimate the three-dimensional dose distribution of protons in the radiochromic gel and polymer gel dosimeter compared with the dose distribution in water. METHODS: The commercial composition ratios of normoxic polymer gel and LCV micelle radiochromic gel were included in this simulation study. The densities of polymer and radiochromic gel were 1.024 and 1...
June 2016: Medical Physics
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