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Yamaguchi, Mitsutaka; Torikai, Kota*; Kawachi, Naoki; Shimada, Hirofumi*; Sato, Takahiro; Nagao, Yuto; Fujimaki, Shu; Kokubun, Motohide*; Watanabe, Shin*; Takahashi, Tadayuki*; et al.
Physics in Medicine & Biology, 61(9), p.3638 - 3644, 2016/05
Times Cited Count：9 Percentile：100(Engineering, Biomedical)no abstracts in English
Yamaguchi, Mitsutaka; Nagao, Yuto; Kawachi, Naoki; Sato, Takahiro; Fujimaki, Shu; Kamiya, Tomihiro; Torikai, Kota*; Shimada, Hirofumi*; Sugai, Hiroyuki*; Sakai, Makoto*; et al.
International Journal of PIXE, 26(1&2), p.61 - 72, 2016/00
no abstracts in English
-ray simultaneous imaging by using a Si/CdTe Compton cameraSuzuki, Yoshiyuki*; Yamaguchi, Mitsutaka; Odaka, Hirokazu*; Shimada, Hirofumi*; Yoshida, Yukari*; Torikai, Kota*; Sato, Takahiro; Arakawa, Kazuo*; Kawachi, Naoki; Watanabe, Shigeki; et al.
Radiology, 267(3), p.941 - 947, 2013/06
Times Cited Count：23 Percentile：65.03(Radiology, Nuclear Medicine & Medical Imaging)Yamaguchi, Mitsutaka; Nagao, Yuto; Kawachi, Naoki; Fujimaki, Shu; Kamiya, Tomihiro; Odaka, Hirokazu*; Kokubun, Motohide*; Takeda, Shinichiro*; Watanabe, Shin*; Takahashi, Tadayuki*; et al.
Proceedings of 2013 IEEE Nuclear Science Symposium and Medical Imaging Conference Record (NSS/MIC), 3 Pages, 2013/00
Yamaguchi, Mitsutaka; Torikai, Kota*; Kawachi, Naoki; Shimada, Hirofumi*; Sato, Takahiro; Nagao, Yuto; Fujimaki, Shu; Kokubun, Motohide*; Watanabe, Shin*; Takahashi, Tadayuki*; et al.
Proceedings of 2013 IEEE Nuclear Science Symposium and Medical Imaging Conference Record (NSS/MIC), 2 Pages, 2013/00
Yamaguchi, Mitsutaka; Torikai, Kota*; Kawachi, Naoki; Shimada, Hirofumi*; Sato, Takahiro; Nagao, Yuto; Fujimaki, Shu; Kokubun, Motohide*; Watanabe, Shin*; Takahashi, Tadayuki*; et al.
Physics in Medicine & Biology, 57(10), p.2843 - 2856, 2012/05
Times Cited Count：41 Percentile：79.35(Engineering, Biomedical)Yamaguchi, Mitsutaka; Kawachi, Naoki; Kamiya, Tomihiro; Sato, Takahiro; Suzui, Nobuo; Fujimaki, Shu; Odaka, Hirokazu*; Ishikawa, Shinnosuke*; Kokubun, Motohide*; Watanabe, Shin*; et al.
JAEA-Review 2011-043, JAEA Takasaki Annual Report 2010, P. 145, 2012/01
no abstracts in English
Yamaguchi, Mitsutaka; Kawachi, Naoki; Suzui, Nobuo; Fujimaki, Shu; Kamiya, Tomihiro; Odaka, Hirokazu*; Ishikawa, Shinnosuke*; Kokubun, Motohide*; Watanabe, Shin*; Takahashi, Tadayuki*; et al.
Nuclear Instruments and Methods in Physics Research A, 648(Suppl.1), p.S2 - S7, 2011/08
Times Cited Count：2 Percentile：19.86(Instruments & Instrumentation)We are constructing a three-dimensional imaging system for medical and biological applications. The system will allow simultaneous imaging at high spatial and energy resolutions across a wide energy range, from several tens of keV to a few MeV. In this work, one prototype head module have been developed for a multi-head Si/CdTe Compton camera system. The performance of the prototype was evaluated with a sealed Ba-133 radiation source. The experiments confirmed that the imaging results were consistent with actual source position. In addition to the resolution for the parallel directions to the detector surface, the position resolution was evaluated for the depth direction at a point in near region of the head-module. These position resolutions were well reproduced by Monte Carlo simulation results.
Yamaguchi, Mitsutaka; Kawachi, Naoki; Kamiya, Tomihiro; Suzui, Nobuo; Fujimaki, Shu; Odaka, Hirokazu*; Ishikawa, Shinnosuke*; Kokubun, Motohide*; Watanabe, Shin*; Takahashi, Tadayuki*; et al.
2010 IEEE Nuclear Science Symposium Conference Record (CD-ROM), p.2004 - 2007, 2010/10
Yamaguchi, Mitsutaka; Kamiya, Tomihiro; Kawachi, Naoki; Suzui, Nobuo; Fujimaki, Shu; Ishioka, Noriko; Watanabe, Shin*; Ishikawa, Shinnosuke*; Odaka, Hirokazu*; Kokubun, Motohide*; et al.
no journal, ,
We have developed a prototype of Si/CdTe medical Compton camera. To overcome low spatial resolution of one head camera, we have proposed multi-head Compton camera. In this work, we studied the spatial resolution by comparing the measured resolution with Monte Carlo simulation. The head of the Compton camera consist of two layers of Si strip detector and two layers of CdTe strip detector. Monte Carlo simulations were performed by using a camera simulator Geant4 toolkit. After the Monte Carlo simulations, imaging process using LM-ML-EM, algorithm was performed in a 3D-space. The measured result was well agree with the simulation result. The spatial resolution is about 6 mm for double-head case while the spatial resolution of depth direction is about 15 mm for single-head case. These results indicate that the spatial resolution is improved and clear 3D-image is taken by using multi-head Compton camera.
ray under the carbon-ion beam therapyYamaguchi, Mitsutaka; Torikai, Kota*; Shimada, Hirofumi*; Kawachi, Naoki; Kamiya, Tomihiro; Suzuki, Yoshiyuki*; Yoshida, Yukari*; Sato, Takahiro; Suzui, Nobuo; Fujimaki, Shu; et al.
no journal, ,
Measurement of the energy distribution of ray under the Carbon-Ion Beam Therapy environment was carried out in order to measure the background for positron annihilation ray peak in the use of in-beam monitoring. In this fiscal year, we studied the effect of the thermal neutron in the irradiation room against a CdTe semiconductor detector. Carbon-ion beam was irradiated on a water phantom and the energy spectrum of ray was measured. The 559 keV ray peak which is emitted from the neutron absorption reaction of Cd-133 are observed in the spectrum. For the case using the boron-paraffin block, the peak is clearly disappeared and the continuous component of the spectrum under the 511 keV annihilation peak decreased and the S/N ratio was refined. Neutron damage of the detector was not observed after the 20 hours use in the 108 pps beam environment.
Yamaguchi, Mitsutaka; Kamiya, Tomihiro; Kawachi, Naoki; Suzui, Nobuo; Fujimaki, Shu; Odaka, Hirokazu*; Ishikawa, Shinnosuke*; Kokubun, Motohide*; Watanabe, Shin*; Takahashi, Tadayuki*; et al.
no journal, ,
We are constructing a three-dimensional imaging system for medical and biological applications as a device that can provide simultaneous imaging, having high spatial and energy resolutions and wide energy range from several tens keV to a few MeV, by diverting the most advanced space-observation technology, Si/CdTe semiconductor Compton camera, developed in ISAS/JAXA. The Si/CdTe Compton camera was developed under the assumption that the use of moderate temperature and the Analog ASIC for signal processing. Moreover, because the solid and thin scattering layer allows close placement of the measured object, good angular resolution corresponds to good spatial resolution directly. These aspects allow construction of compact medical system. In contrast to space-observation use, three-dimensional imaging ability becomes important for life science research. In order to achieve a good three-dimensional spatial resolution, modularizing the Compton camera into a small camera head and allowing multi-angle imaging with multi-head structure is required. In this work, a head module has been developed as a prototype module of the multi-head system. Sensor and circuit modules are closely arranged and put in a compact vacuum-insulating cylindrical housing. Each of camera heads will be fixed on robot arms and be able to adjust the positions and the directions. Performance evaluation test was made for the prototype module with a sealed Ba-133 radiation source. We confirmed that the imaging result is consistent with the source positioning. The angular resolution measure, abbreviated as ARM, was estimated to be 4.5 degree. The result of the test was compared with a Monte Carlo simulation study. We will report the details of the prototype module and the result of the performance evaluation test. The expecting three-dimensional performance will also be reported.
Yamaguchi, Mitsutaka; Kamiya, Tomihiro; Kawachi, Naoki; Suzui, Nobuo; Ishioka, Noriko; Fujimaki, Shu; Watanabe, Shin*; Ishikawa, Shinnosuke*; Odaka, Hirokazu*; Kokubun, Motohide*; et al.
no journal, ,
no abstracts in English
Yamaguchi, Mitsutaka; Kawachi, Naoki; Suzui, Nobuo; Fujimaki, Shu; Kamiya, Tomihiro; Odaka, Hirokazu*; Ishikawa, Shinnosuke*; Kokubun, Motohide*; Watanabe, Shin*; Takahashi, Tadayuki*; et al.
no journal, ,
no abstracts in English
Yamaguchi, Mitsutaka; Kawachi, Naoki; Suzui, Nobuo; Fujimaki, Shu; Kamiya, Tomihiro; Odaka, Hirokazu*; Kokubun, Motohide*; Takeda, Shinichiro*; Ishikawa, Shinnosuke*; Watanabe, Shin*; et al.
no journal, ,
no abstracts in English
Kawachi, Naoki; Yamaguchi, Mitsutaka; Nagao, Yuto; Suzui, Nobuo; Fujimaki, Shu; Kamiya, Tomihiro; Odaka, Hirokazu*; Kokubun, Motohide*; Takeda, Shinichiro*; Ishikawa, Shinnosuke*; et al.
no journal, ,
-ray sources at close range using Si/CdTe Compton cameraNagao, Yuto; Yamaguchi, Mitsutaka; Kawachi, Naoki; Fujimaki, Shu; Kamiya, Tomihiro; Takeda, Shinichiro*; Odaka, Hirokazu*; Watanabe, Shin*; Kokubun, Motohide*; Takahashi, Tadayuki*; et al.
no journal, ,
A conventional -ray imaging system such as a gamma camera and SPECT has a fundamental problem that imposes a tradeoff between sensitivity and spatial resolution and restricts -ray energy to low because of the physical constraints resulting from the mechanical collimation. On the other hand, a Compton camera, which applies kinematics of Compton scattering to the electronic collimation, is a next generation -ray imaging system which decouples the tradeoff between sensitivity and spatial resolution and covers a wide range of energy. We study an application of a Si/CdTe semiconductor Compton camera being developed for space observation to in vivo tracer imaging in medicine and biology. Particularly, it is essential for a medical and biological application to estimate quantitative distribution of tracers in a field close to the camera. We developed an image reconstruction method to realize quantitative profiling of -ray emitting sources.
Nagao, Yuto; Yamaguchi, Mitsutaka; Kawachi, Naoki; Fujimaki, Shu; Kamiya, Tomihiro; Takeda, Shinichiro*; Watanabe, Shin*; Takahashi, Tadayuki*; Torikai, Kota*; Arakawa, Kazuo*; et al.
no journal, ,
no abstracts in English
Yamaguchi, Mitsutaka; Nagao, Yuto; Kawachi, Naoki; Fujimaki, Shu; Arakawa, Kazuo*; Kamiya, Tomihiro; Odaka, Hirokazu*; Kokubun, Motohide*; Takeda, Shinichiro*; Watanabe, Shin*; et al.
no journal, ,
no abstracts in English
Nagao, Yuto; Yamaguchi, Mitsutaka; Kawachi, Naoki; Fujimaki, Shu; Kamiya, Tomihiro; Takeda, Shinichiro*; Watanabe, Shin*; Takahashi, Tadayuki*; Torikai, Kota*; Arakawa, Kazuo*; et al.
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