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JAEA Reports

Estimation methods of blood boron concentration and error evaluation during boron neutron capture therapy for malignant brain tumor

Shibata, Yasushi*; Yamamoto, Kazuyoshi; Matsumura, Akira*; Yamamoto, Tetsuya*; Hori, Naohiko; Kishi, Toshiaki; Kumada, Hiroaki; Akutsu, Hiroyoshi*; Yasuda, Susumu*; Nakai, Kei*; et al.

JAERI-Research 2005-009, 41 Pages, 2005/03

JAERI-Research-2005-009.pdf:1.99MB

The measurement of neutron flux and boron concentration in the blood during medical irradiation is indispensable in order to evaluate the radiation in boron neutron capture therapy. It is, however, difficult to measure the blood boron concentration during neutron irradiation because access to the patient is limited. Therefore we prospectively investigated the predictability of blood boron concentrations using the data obtained at the first craniotomy after infusion of a low dosage of BSH. When the test could not be carried out, the blood boron concentration during irradiation was also predicted by using the 2-compartment model. If the final boron concentration after the end of the infusion is within 95% confidence interval of the prediction, direct prediction from biexponential fit will reduce the error of blood boron concentrations during irradiation to around 6%. If the final boron concentration at 6 or 9 hours after the end of infusion is out of 95% confidence interval of the prediction, proportional adjustment will reduce error and expected error after adjustment to around 12%.

Journal Articles

Combination of boron and gadolinium compounds for neutron capture therapy; An $$in Vitro$$ study

Matsumura, Akira*; Zhang, T.*; Nakai, Kei*; Endo, Kiyoshi*; Kumada, Hiroaki; Yamamoto, Tetsuya*; Yoshida, Fumiyo*; Sakurai, Yoshinori*; Yamamoto, Kazuyoshi; Nose, Tadao*

Journal of Experimental and Clinical Cancer Research, 24(1), p.93 - 98, 2005/03

no abstracts in English

Journal Articles

Application of invasion mathematical model in dosimetry for boron neutron capture therapy for malignant glioma

Yamamoto, Kazuyoshi; Kumada, Hiroaki; Nakai, Kei*; Endo, Kiyoshi*; Yamamoto, Tetsuya*; Matsumura, Akira*

Proceedings of 11th World Congress on Neutron Capture Therapy (ISNCT-11) (CD-ROM), 14 Pages, 2004/10

A dose distribution considered the tumor cell density distribution is required on the radiation therapy. We propose a novel method of determining target region considering the tumor cell concentration as a new function for the next generation Boron Neutron Capture Therapy (BNCT) dosimetry system. It has not been able to sufficiently define the degree of microscopic diffuse invasion of the tumor cells peripheral to a tumor bulk in malignant glioma using current medical imaging. Referring to treatment protocol of BNCT, the target region surrounding the tumor bulk has been set as the region which expands at the optional distance with usual 2cm margin from the region enhanced on T1 weighted gadolinium Magnetic Resonance Imaging (MRI). In this research, the cell concentration of the region boundary of the target was discussed by using tumor cell diffusion model in the sphere spatio-temporal system. The survival tumor cell density distribution after the BNCT irradiation was predicted by the two regions diffusion model for a virtual brain phantom.

Journal Articles

Analysis of intracellular distribution of boron and gadolinium in 9L sarcoma cells using a single-ended accelerator (Micro PIXE)

Endo, Kiyoshi*; Shibata, Yasushi*; Yoshida, Fumiyo*; Nakai, Kei*; Yamamoto, Tetsuya*; Matsumura, Akira*; Ishii, Keizo*; Sakai, Takuro; Sato, Takahiro; Oikawa, Masakazu*; et al.

Proceedings of 11th World Congress on Neutron Capture Therapy (ISNCT-11) (CD-ROM), 2 Pages, 2004/10

Micro PIXE, which is installed in a single end accelerator in JAERI, was used for quantitative analysis of boron and gadolinium distribution in a cell level. The micro beam of 1 $$mu$$m diameter is possible to observe the distribution. In the adjustment procedure of the sample, first is a fix of mylar film by using a glass ring and a bite ring of 2cm diameter. Next the 9L cells were scattered on the washed film, and is cultivated on 37$$^{circ}$$C in medium until they form the mono-layer. After the Gd-BOPTA was added, it incubates for the 24-72 hour on 37$$^{circ}$$C. The film is washed in the THAM liquid, and is directly put on liquid nitrogen. A vacuum drying for 24 hours is conducted in order to fix a film on holder. It is important to uniformly fix the cell in distribution analysis in the cell using Micro PIXE. In recent result, it became possible that the distribution of P, S, Gd, etc. was analyzed. But we could not distinguish whether K and Gd exist in the cell or whether it exists around the cell. It was indicated that these elements was leaked by the reason of cell breaking or other on the cytoplasm.

Journal Articles

Reproducibility of thermal neutron flux distribution on patient's brain surface with a realistic phantom

Yamamoto, Kazuyoshi; Kumada, Hiroaki; Yamamoto, Tetsuya*; Matsumura, Akira*

Nippon Genshiryoku Gakkai Wabun Rombunshi, 3(2), p.193 - 199, 2004/06

To investigate the possibility of experimental approach for dose evaluation using a realistic phantom that faithfully reproduced the shape of a head, this research considered the manufacture of a patient's realistic phantom and the reappearance of actual medical irradiation conditions. We selected the rapid prototyping technology to produce the realistic phantom from the Computed Tomography (CT) imaging. This phantom was irradiated under the same clinical irradiation condition of this patient, and the thermal neutron distribution on the brain surface was measured in detail. Several subjects on material and data conversion in the production of realistic phantom were mentioned. As a result of reproducing medical irradiation using the realistic phantom, the maximum thermal neutron flux became a value about 22% lower than the surface of the actual brain. If the problems pointed out in this paper are solved, it may also be expected that it would become possible to check computational dosimetry system.

Journal Articles

Characterization of neutron beams for boron neutron capture therapy; In-air radiobiological dosimetry

Yamamoto, Tetsuya*; Matsumura, Akira*; Yamamoto, Kazuyoshi; Kumada, Hiroaki; Hori, Naohiko; Torii, Yoshiya; Shibata, Yasushi*; Nose, Tadao*

Radiation Research, 160(1), p.70 - 76, 2003/07

 Times Cited Count:13 Percentile:62.08(Biology)

The survival curves and the RBE for the dose components generated in boron neutron capture therapy (BNCT) were determined separately in neutron beams at JRR-4. The surviving fractions of V79 cells with or without 10B were obtained using an epithermal neutron beam (ENB), a mixed thermal-epithermal neutron beam (TNB-1), and a thermal (TNB-2) neutron beam. The cell killing effect of the neutron beam in the presence or absence of 10B was highly dependent on the neutron beam used and depended on the epithermal and fast-neutron content of the beam. The RBEs of the boron capture reaction were 4.07, 2.98 and 1.42, and the RBEs of the high-LET dose components based on the hydrogen recoils and the nitrogen capture reaction were 2.50, 2.34 and 2.17 for ENB, TNB-1 and TNB-2, respectively. The approach to the experimental determination of RBEs allows the RBE-weighted dose calculation for each dose component of the neutron beams and contributes to an accurate inter-beam comparison of the neutron beams at the different facilities employed in ongoing and planned BNCT clinical trials.

Journal Articles

Clinical review of the Japanese experience with boron neutron capture therapy and a proposed strategy using epithermal neutron beams

Nakagawa, Yoshinobu*; Pooh, K. H.*; Kobayashi, Toru*; Kageji, Teruyoshi*; Uyama, Shinichi*; Matsumura, Akira*; Kumada, Hiroaki

Journal of Neuro-Oncology, 62(1), p.87 - 99, 2003/04

 Times Cited Count:105 Percentile:17.74

Our concept of boron neutron capture therapy (BNCT) is selective destruction of tumor cells using the heavy-charged particles Yielded through 10B(n, alpha)7 Li reactions. In the analysis of side effects due to radiation, we included all the 159 patients treated between 1977 and 2001. With respect to the radiation dose (i.e. physical dose of boron n-alpha reaction), the new protocol prescribes a minimum tumor volume dose of 15Gy or, alternatively, a minimum target volume dose of 18Gy. The maximum vascular dose should not exceed 15Gy (physical dose of boron n-alpha reaction) and the total amount of gamma rays should remain below 10Gy, including core gamma rays from the reactor and capture gamma in brain tissue. The outcomes for 10 patients who were treated by the new protocol using a new mode composed of thermal and epithermal neutrons are reported.

JAEA Reports

Production of a faithful realistic phantom to human head and thermal neutron flux measurement on the brain surface (Cooperative research)

Yamamoto, Kazuyoshi; Kumada, Hiroaki; Kishi, Toshiaki; Torii, Yoshiya; Endo, Kiyoshi*; Yamamoto, Tetsuya*; Matsumura, Akira*; Uchiyama, Junzo; Nose, Tadao*

JAERI-Tech 2002-092, 23 Pages, 2002/12

JAERI-Tech-2002-092.pdf:5.22MB

Thermal neutron flux is determined using the gold wires in current BNCT irradiation, so evaluation of arbitrary points after the irradiation is limited in the quantity of these detectors. In order to make up for the weakness, dose estimation of a patient is simulated by a computational dose calculation supporting system. In another way without computer simulation, a medical irradiation condition can be replicate experimentally using of realistic phantom which was produced from CT images by rapid prototyping technique. This phantom was irradiated at a same JRR-4 neutron beam as clinical irradiation condition of the patient and the thermal neutron distribution on the brain surface was measured in detail. This experimental evaluation technique using a realistic phantom is applicable to in vitro cell irradiation experiments for radiation biological effects as well as in-phantom experiments for dosimetry under the nearly medical irradiation condition of patient.

Journal Articles

Simple estimation method of $$gamma$$-ray dose using low neutron-sensitive TLD (UD-170LS) for Intra-Operative Boron Neutron Capture Therapy (IOBNCT)

Yamamoto, Kazuyoshi; Kumada, Hiroaki; Torii, Yoshiya; Kishi, Toshiaki; Yamamoto, Tetsuya*; Matsumura, Akira*

Research and Development in Neutron Capture Therapy, p.499 - 503, 2002/09

In order to estimate the maximum gamma-ray dose in the brain in Intra-Operative Boron Neutron Capture Therapy (IOBNCT), this study was conducted for (1) the development of low neutron-sensitive TLD (UD-170LS-T2), (2) the correlation of capture gamma-ray dose profile in a phantom for various collimator sizes, and (3) the formula for simple estimation of maximum gamma-ray dose on IOBNCT. The sensitivity of TLD, as $$^{60}$$Co $$gamma$$-ray equivalent, for thermal neutron was 5.1$$pm$$0.8$$times$$10$$^{-14}$$($$^{60}$$Co-Gycm$$^{2}$$)The average relative deviations between predicted and measured $$gamma$$-ray dose for the mixed epithermal-thermal neutron beam in the phantom were $$pm$$8.5%. The accuracy of the $$gamma$$-ray dose determination in the clinical BNCT may be improved by this simple method.

Journal Articles

The Prediction of Boron concentrations in blood for patients of boron neutron capture therapy, 2

Shibata, Yasushi*; Matsumura, Akira*; Yamamoto, Tetsuya*; Akutsu, Hiroyoshi*; Yasuda, Susumu*; Nakai, Kei*; Nose, Tadao*; Yamamoto, Kazuyoshi; Kumada, Hiroaki; Hori, Naohiko; et al.

Research and Development in Neutron Capture Therapy, p.1055 - 1060, 2002/09

We prospectively investigated the predictability of blood boron concentrations using the data obtained at the first craniotomy after infusion of a low dose of sodium undecahydroclosododecaborate (BSH). Nine patients with malignant glial tumors underwent Boron neutron capture therapy (BNCT) at the Japan Atomic Energy Research Institute (JAERI) between 1995 and 2001. In 7 patients, 1g of BSH was infused before the first tumor removal and boron concentrations were determined using prompt gamma ray analysis (PGA). Then, 12 hours before BNCT, patients were infused at a dose of 100mg/kg BSH, and the boron concentrations were determined again. The boron biodistribution data showed a biexponential pharmacokinetic profile. If the final boron concentration at 6 or 9 hours after the end of the infusion is within the 95% confidence interval of the prediction, direct prediction from biexponential fit will reduce the error of blood boron concentrations during irradiation to around 6%.

Journal Articles

Intraoperative boron neutron capture therapy using thermal/epithermal mixed beam

Matsumura, Akira*; Yamamoto, Tetsuya*; Shibata, Yasushi*; Nakai, Kei*; Zhang, T.*; Matsushita, Akira*; Takano, Shingo*; Endo, Kiyoshi*; Akutsu, Hiroyoshi*; Yamamoto, Kazuyoshi; et al.

Research and Development in Neutron Capture Therapy, p.1073 - 1078, 2002/09

Since 1998 to 2002, a new clinical trial of an intraoperative boron neutron capture therapy (IOBNCT) at JRR-4 of Japan Atomic Energy Institute (JAERI) using BSH with mixed thermal/epithermal neutron beam has been accomplished. There have been 9 patients included in this study. The median survival time (MST) in GBM was 19.8 months and 16.8 months in AA. IOBNCT with mixed thermal/epithermal neutron beam provide better primary radiation effect than conventional therapy in selected cases. Our phase I/II clinical trial was effective in local tumor control. Further clinical trial with new design should be performed to prove the efficacy of IOBNCT.

Journal Articles

Comparison of dosimetry by the realistic patient head phantom and by the patient's brain, and the JCDS calculation; A Clinical dosimetry study

Endo, Kiyoshi*; Matsumura, Akira*; Yamamoto, Tetsuya*; Nose, Tadao*; Yamamoto, Kazuyoshi; Kumada, Hiroaki; Kishi, Toshiaki; Torii, Yoshiya; Kashimura, Takanori*; Otake, Shinichi*

Research and Development in Neutron Capture Therapy, p.425 - 430, 2002/09

Using the Rapid Prototyping Technique, we produced a realistic phantom as a formative model of a patient head. This realistic phantom will contribute to verification of our planning system. However, cross-correlation among the calculations using the JAERI Computational Dosimetry System (JCDS), the realistic phantom, and the in vivo measurements were not fully completed because of the difficulty involved in modeling a post-surgical brain and a thermal neutron shield. The experimental simulation technique using the realistic phantom is a useful tool for more reliable dose planning for the intraoperative BNCT.

Journal Articles

An Application to Intraoperative BNCT using epithermal neutron of new JRR-4 mode "Epi-12"

Matsushita, Akira*; Yamamoto, Tetsuya*; Matsumura, Akira*; Nose, Tadao*; Yamamoto, Kazuyoshi; Kumada, Hiroaki; Torii, Yoshiya; Kashimura, Takanori*; Otake, Shinichi*

Research and Development in Neutron Capture Therapy, p.141 - 143, 2002/09

A thermal-epithermal mixed beam "Thermal Neutron Beam Mode I" was used in the eleven sessions of boron neutron capture therapy which have been performed at JRR-4 from 1998. We are planning to use an epithermal beam for the treatment of deeper tumors in the next trial of the intraoperative BNCT. In this study, "Epi-12" which was made by putting up a cadmium shutter of "Thermal Neutron Beam Mode I" was investigated for the clinical benefits and safety by epithermal beams. Decrease of fast neutron contamination ratio in Epi-12 mode is the advantage for BNCT, particular in the intraoperative BNCT. Because fast neutron on the brain surface is one of the critical factors in the intraoperative BNCT in which the plain beam directly interacts the normal structures. Furthermore a mixture of mode Epi-12 and Th-12 will provide various dose distribution designs. It may be used as a new method to control the best distribution for individual tumors.

Journal Articles

A Combination use of boron and gadolinium compounds in ${it In vitro}$ NCT trial

Zhang, T.*; Matsumura, Akira*; Yamamoto, Tetsuya*; Yoshida, Fumiyo*; Sakurai, Yoshinori*; Kumada, Hiroaki; Yamamoto, Kazuyoshi; Nose, Tadao*

Research and Development in Neutron Capture Therapy, p.819 - 824, 2002/09

From present study, the irradiation effect by using combination of Boron and Gd, showed various irradiation effects (additive effect, less than additive effect, non additive effect), which depend on Gd concentration. The additive effect will be occurred when using a combination of Gd and Boron with low concentration, however, adding Gd to high concentration will reduce additive effect resulting in less than additive to finally non-additive effect. This result indicate that achieving suitable concentrations of Gd and Boron together in tumors may increase the therapy effect, but achieving excess concentration of Gd with Boron together in tumor may cause negative therapeuitic effect.

Journal Articles

In-phantom two-dimensinal thermal neutron distribution for intraoperative boron neutron capture therapy of brain tumours

Yamamoto, Tetsuya*; Matsumura, Akira*; Yamamoto, Kazuyoshi; Kumada, Hiroaki; Shibata, Yasushi*; Nose, Tadao*

Physics in Medicine & Biology, 47(14), p.2387 - 2396, 2002/07

 Times Cited Count:17 Percentile:52.61(Engineering, Biomedical)

The aim of this study was to determine the in-phantom thermal distribution derived from neutron beams for intraoperative boron neutron capture therapy (IOBNCT). Gold activation wires arranged in a cylindrical water phantom with (void-in phantom) or without (standard phantom) a cylinder styrene form placed inside were irradiated by using the epithermal beam (ENB) and the mixed thermal-epithermal beam (TNB-1) at the JRR-4. The thermal neutron distribution derived from both the ENB and TNB-1 was significantly improved in the void-in-phantom, and a double high dose area was formed lateral to the void. The flattened distribution in the circumference of the void was observed with the combination of ENB and the void-in-phantom. The measurement data suggest that the ENB may provide a clinical advantage in the form of an enhanced and flattened dose delivery to the marginal tissue in which residual and/or microscopically infiltrating tumor.

JAEA Reports

${it In vitro}$ biological effectiveness of JRR-4 epithermal neutron beam; Experiment under free air beam and in water phantom (Cooperative research)

Yamamoto, Tetsuya*; Yamamoto, Kazuyoshi; Matsumura, Akira*; Kumada, Hiroaki; Kishi, Toshiaki; Hori, Naohiko; Torii, Yoshiya; Horiguchi, Yoji; Nose, Tadao*

JAERI-Research 2002-011, 56 Pages, 2002/05

JAERI-Research-2002-011.pdf:3.17MB

The surviving curve and RBE of dose components generated in boron neutron capture therapy (BNCT) were separately determined in neutron beams at JRR-4. Surviving fraction of V79 cell with or without $$_{10}$$B was obtained using an epithermal neutron beam (ENB), a mixed thermal-epithermal neutron beam (TNB-1), and a thermal neutron beam(TNB-2), which were used or planned to use for clinical trial. The cell killing effect of these beams depended highly on the neutron beam used, according to the epithermal and fast neutron content in the beam. RBE of the boron capture were 3.99$$pm$$0.24, 3.04$$pm$$0.19 and 1.43$$pm$$0.08, RBE of the high-LET dose components based were 2.50$$pm$$0.32, 2.34$$pm$$0.30 and 2.17$$pm$$0.28 for ENB, TNB-1 and TNB-2, respectively. The experimental determination of biological effectiveness factor outlined in this paper is applicable to the dose calculation for each dose component of the neutron beams and contribute to an accurate RBE as comparison with a neutron beam at a different facility employed in ongoing and planned BNCT clinical trials.

JAEA Reports

Evaluation of JRR-4 neutron beam using tomor cells (Cooperative research)

Yamamoto, Kazuyoshi; Yamamoto, Tetsuya*; Kumada, Hiroaki; Torii, Yoshiya; Kishi, Toshiaki; Matsumura, Akira*; Nose, Tadao*; Horiguchi, Yoji

JAERI-Tech 2001-017, 38 Pages, 2001/03

JAERI-Tech-2001-017.pdf:2.5MB

no abstracts in English

JAEA Reports

Inverstigation of current status in Europe and USA on boron neutron capture therapy (Contract research)

Research Reactor Utilization Division

JAERI-Tech 2000-064, 76 Pages, 2000/11

JAERI-Tech-2000-064.pdf:6.61MB

no abstracts in English

JAEA Reports

Proceedings of Neutron Irradiation Technical Meeting on BNCT; March 13, 2000, at JAERI Tokai Research Establishment

Department of Research Reactor

JAERI-Conf 2000-013, 69 Pages, 2000/10

JAERI-Conf-2000-013.pdf:14.75MB

no abstracts in English

19 (Records 1-19 displayed on this page)
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