採用情報
ラボラトリー
【統合腫瘍学研究部門】
【内分泌代謝・シグナル学研究部門】
【元素科学研究部門】
【海外ラボラトリー】
国立大学法人 群馬大学
JREC-IN

統合腫瘍学研究部門

Parajuli研究員

Raj Kumar PARAJULI
Raj Kumar PARAJULI
職名:ポスドク

研究テーマ

Development of Compton Imaging System

Characterization of cancer with respect to its surroundings tissue is a very important aspect of current medical imaging systems, which can ease the medical diagnosis and treatment strategy. Even with the current imaging techniques like PET and SPECT, the problems remain unsolved because of the imaging principles; requirement of a mechanical collimator or coincident detection of annihilation gamma rays. Effective use of Compton cameras, which were originally developed for astronomy, could be a great innovation to overcome the current problems in diagnostic imaging because of its simultaneous imaging ability against wide energy range. Currently we are developing a 3-dimentional nuclear imaging system based on the high-tech Si/CdTe semiconductor cameras developed by Japan Aerospace Exploration Agency (JAXA). In the meanwhile we are also implementing our immense effort in enhancing the resolution and accuracy of current imaging technique followed by developing high speed imaging mechanism.
Yet another research, we are implementing our Compton camera (ASTROCAM 7000HS) for the real-time beam monitoring in carbon ion radiotherapy facility. We perform measurement and imaging of 511 keV annihilation gammas and 718 keV prompt gammas emissions due to interaction of particle beams with target, for a precise verification of dose distribution.

Radiation Measurement using RPL glass Micro-dosimeter

Heavy Ion Cancer therapy has been increasing worldwide due to its high linear transfer (LET) and unique dose distribution at Bragg peak with sharp increase of dose in well-defined depth and rapid fall-off beyond that maximum. In this research, we attempt to enhance the current system by developing a precise dose distribution measurement tool so called the micro-dosimeter, which is necessary to treat cancer with high accuracy minimizing the side effects. If we can develop and implement highly reliable radio-photoluminescence (RPL) glass dosimeter with size less than millimeters, it could be possible to visualize three-dimensional dose distribution. Therefore in this research we aim to develop micrometer sized radiation dosimeter for realizing convenient three-dimensional dose distribution evaluation method for radiation therapy.

主要業績

論文

*R. K. Parajuli, M. Sakai, W. Kada, K. Torikai, M. Kikuchi, K. Arakawa, M. Torikoshi, and T. Nakano, “Annihilation Gamma Imaging for Carbon Ion Beam Range Monitoring using Si/CdTe Compton Camera”, Phys. Med. Biol., 64 (2019) 055003. (Peer Review)

*Sakai, R. K. Parajuli, M. Kikuchi, M. Yamaguchi, Y. Nagao, N. Kawachi, K. Arakawa, and T. Nakano, “Effect of Number of Views on Cross-sectional Compton Imaging: A Fundamental Study with Backprojection”, Physica Medica, 56 (2018). (Peer-Review)

*W. Kada, I. Sudic, N. Skukan, S. Kawabata, T. Satoh, J. Susaki, S. Yamada, T. Sekine, R. K. Parajuli, M. Sakai, K. Miura, M. Koka, N. Yamada, T. Kamiya, M. Jaksic, and O. Hanaizumi, “Evaluation of Scintillation Properties of α- and β-SiAlON phosphors under focused microbeam irradiation using ion-beam-induced luminescence analysis”, Nucl. Instr. Meth. B., (In Press, Peer Review)

*M. Yamaguchi, Y. Nagao, K. Ando, S. Yamamoto, M. Sakai, R. K. Parajuli, K. Arakawa, and N. Kawachi, “Imaging of Monochromatic Beams by Measuring Secondary Bremsstrahlung for Carbon-ion Therapy using a Pinhole X-ray Camera”, Phys. Med. Biol., 63 (2018) 045016. (Peer Review)

*W. Kada, S. Kawabata, T. Satoh, M. Sakai, R. K. Parajuli, N. Yamada, M. Koka, K. Miura, O. Hanaizumi, and T. Kamiya, “Observation of Changes in Ion Beam Induced Luminescence Spectra from Organics during Focused Microbeam Irradiation”, Nucl. Instr. Meth. B., 404 (2017) 100-105. (Peer Review)

*W. Kada, S. Kawabata, T. Satoh, R. K. Parajuli, N. Yamada, M. Koka, K. Miura, O. Hanaizumi, and T. Kamiya, “Development of High-speed Wavelength-dispersive IBIL Analysis and Imaging System Using a Multi-channel Photon-counting Spectrometer”, Nucl. Instr. Meth. B., 406 (2017) 124-129. (Peer Review)

*S. Kawabata, W. Kada, Y. Matsubara, T. Satoh, M. Sakai, R. K. Parajuli, N. Yamada, M. Koka, K. Miura, O. Hanaizumi, and T. Kamiya, “Micro-PIXE Analysis and Imaging of Radio-photoluminescence Glass Bead Microdosimeters”, Nucl. Instr. Meth. B., 406 (2017) 139-143. (Peer Review)

*R. K. Parajuli, R. Saruya, N. Akutzu, S. Miura, W. Kada, S. Kawabata, Y. Matsubara, T. Satoh, M. Koka, N. Yamada, T. Kamiya, K. Miura, and O. Hanaizumi, “Fabrication and Evaluation of Flexible Mach-Zehnder Waveguide Structure Embedded in a Poly(dimethylsiloxane) Thin Film using a Proton Microbeam”, Jpn. J. Appl. Phys., 55 (2016) 06GD01. (Peer Review)

*R. K. Parajuli, W. Kada, S. Kawabata, Y. Matsubara, K. Miura, A. Yokoyama, M. Haruyama, M. Sakai, and O. Hanaizumi, “Evaluation of Radio-photoluminescence Spectra of Copper-doped Phosphate Glass Dosimeter Irradiated with Ionized Particles”, Key. Eng. Mat., 698 (2016) 163-170. (Peer Review)

*R. K. Parajuli, W. Kada, S. Kawabata, Y. Matsubara, M. Sakai, K. Miura, T. Satoh, M. Koka, N. Yamada, T. Kamiya, and O. Hanaizumi, “Ion Beam Induced Luminescence (IBIL) Analysis for β-SiAlON:Eu Scintillator under Focused Micro-beam Irradiation”, Sen. Mat., 28 (2016) 837-844. (Peer Review)

*S. Kawabata, W. kada, R. K. Parajuli, Y. Matsubara, K. Miura, T. Satoh, M. Koka, N. Yamada, T. Kamiya and O. Hanaizumi, “ Complex system of Proton Beam Writing (PBW) and In-situ Ion Beam Induced Luminescence (IBIL) Analysis using Proton Microbeam Probe for the Evaluation of Micrometer-sized RPL Glass Dosimeter”, Jpn. J. Appl. Phys., 55 (2016) 06GD03. (Peer Review)

*R. K. Parajuli, N. Sunaguchi, R. Tei, T. Iijima, and Y. Yamakoshi, “Characterization of nonlinearity of shear elasticity using local velocity mapping”, Jpn. J. Appl. Phys. 53 (2014) 07KF30. (Peer Review)

*R. K. Parajuli, R. Tei, D. Nakai, and Y. Yamakoshi, “Share wave imaging using phase modulation component of harmonic distortion in continuous shear wave excitation”, Jpn. J. Appl. Phys. 52 (2013) 07HF22. (Peer Review)

*T. Miwa, Y. Yoshihara, K. Kanzawa, R. K. Parajuli, and Y. Yamakoshi, “Tissue viscoelasticity measurement system by simultaneous multiple-frequency excitation”, Jpn. J. Appl. Phys. 51 (2012) 07GF13. (Peer Review)

*T. Miwa, R. K. Parajuli, R. Tomizawa, and Y. Yamakoshi, “Shear wave velocity estimation by virtual sensing array spectrum analysis”, Jpn. J. Appl. Phys. 50 (2011) 07HF07. (Peer Review)

学会発表

R. K. Parajuli, M. Sakai, W. Kada, K. Torikai, M. Kikuchi, K. Arakawa, M. Torikoshi, and T. Nakano, “Annihilation Gamma Imaging for Carbon Ion Beam Range Monitoring using Si/CdTe Compton Camera”, 2018 IEEE Nuclear Science Symposium and Medical Imaging Conference: 16th November 2018, Sydney, Australia.

M. Yamaguchi, Y. Nagao, K. Ando, S. Yamamoto, M. Sakai, R. K. Parajuli, K. Arakawa, and N. Kawachi, “Simulation Study on Imaging of a Monochromatic Carbon Beam by Measuring Secondary Electron Bremsstrahlung”, Micro-Mini & Nano Dosimetry (MMND) Workshop 2018: 8th February 2018, Queensland, Australia.

M. Yamaguchi, Y. Nagao, K. Ando, S. Yamamoto, M. Sakai, R. K. Parajuli, K. Arakawa, and N. Kawachi, “Imaging of Monochromatic Beam by Measuring Secondary Electron Bremsstrahlung for Carbon-ion Therapy”, 2017 IEEE Nuclear Science Symposium and Medical Imaging Conference: 27th October 2017, Georgia, USA.

M. Sakai, R. K. Parajuli, M. Kikuchi, K. Arakawa, M. Yamaguchi, Y. Nagao, N. Kawachi, and T. Nakano, “The Impact of Number of Views on Cross-sectional Compton Imaging”, 114th Japan Society of Medical Physics (JSMP 2017): 15th September 2017, Osaka, Japan.

M. Sakai, R. K. Parajuli, M. Kikuchi, K. Arakawa, M. Yamaguchi, Y. Nagao, N. Kawachi, S. Takeda, T. Takahashi, and T. Nakano, “Comparison of Yttrium-90 Compton Image, SPECT, and PET”, 113th Japan Society of Medical Physics (JSMP 2017): 13th April 2017, Yokohama, Japan.

R. K. Parajuli, W. Kada, M. Sakai, S. Kawabata, Y. Matsubara, T. Kamiya, T. Satoh, K. Miura, and O. Hanaizumi, “Evaluation of Radio-photoluminescence Glass Beads Dosimeter using Micro-PIXE Analysis and Imaging”, 77th Japan Society of applied Physics Autumn Meeting (JSAP 2016): 15th September 2016, Niigata, Japan.

R. K. Parajuli, R. Saruya, K. Miura, W. Kada, S. Kawabata, Y. Matsubara, H. Kato, A. Yokoyama, M. Koka, T. Satoh, Y. Ishii, T. Kamiya, H. Nishikawa and O. Hanaizumi, “Fabrication and In-situ Evaluation of Completely-Flexible MZ Waveguide Structure Embedded in PDMS Thin Film using Focused Proton Microbeam”, 28th International Microprocesses and Nanotechnology Conference (MNC 2015): 11th Nov. 2015, Toyama, Japan. (12P-7-5).

R. K. Parajuli, S. Kawabata, Y. Matsubara, W. Kada, M. Sakai, K. Miura, T.Satoh, M. Koka, N. Yamada, T. Kamiya, and O. Hanaizumi, “Radiation Tolerability Evaluation of SiAlON Scintillator using Ion Beam Induced Luminescence (IBIL) Analysis”, 76th Japan Society of applied Physics Autumn Meeting (JSAP 2015): 13th Sep. 2015, Nagoya, Japan. (13p-PA7-44).

R. K. Parajuli, and Y. Yamakoshi, “Impact of Odd-Even Phase Modulated Harmonic Components in Nonlinearity of Shear Elasticity”, The 35th Symposium on Ultrasonic Electronics (USE 2014): 4th Dec. 2014, Tokyo, Japan. (2P2-8).

R. K. Parajuli, N. Sunaguchi, R. Tei, T. Iijima and Y. Yamakoshi, “Evaluation of Local Velocity Mapping for Nonlinearity of Shear Elasticity”, The 34th Symposium on Ultrasonic Electronics (USE 2013): 21st Nov. 2013, Kyoto, Japan. (2E5-2).

R. K. Parajuli, N. Sunaguchi, R. Tei, T. Iijima and Y. Yamakoshi, “Analysis of Nonlinearity of Shear Elasticity in Continuous Shear Wave Imaging System”, 5th International Symposium Conference on Advanced Micro Device Engineering (AMDE 2013): 19th Dec. 2013, Gunma, Japan. (P12).

R. K. Parajuli, R. Tei, D. Nakai, and Y. Yamakoshi, “Shear Wave Imaging using Phase Modulation Component of Harmonic Distortion in Continuous Shear Wave Excitation”, The 33rd Symposium on Ultrasonic Electronics (USE2012): 14th Nov. 2012, Chiba, Japan. (2P5-5).

R. K. Parajuli, D. Nakai, R. Tei and Y. Yamakoshi, “Local Velocity Mapping to Reconstruct the Phase Modulation Component in Continuous Shear Wave Excitation”, 4th International Conference on Advanced Micro Device Engineering (AMDE 2012): 7th Dec. 2012, Kiryu, Japan. (P03).

Y. Yamakoshi, R.K. Parajuli, R. Tei, and D. Nakai, “Shear Wave Imaging using Harmonic Distortion of Sinusoidal Excitation”, 11th International Tissue Elasticity Conference (ITEC 2012): 5th Oct.2012, Normandy, France. (004, Pg. 93).

Takashi Miwa, R.K. Parajuli, and Y. Yamakoshi, “Novel Tissue Elasticity Imaging by 3-D low Frequency Vibration Wave Measurement”, 13th World Congress of Ultrasound in Medicine and Biology (WFUMB 2011): 26th Aug. 2011, Vienna, Austria.

受賞

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