Updated on 2022/10/18

写真a

 
NAKANISHI Kouhei
 
Organization
Graduate School of Medicine Assistant Professor
Graduate School
Graduate School of Medicine
Undergraduate School
School of Health Sciences
Title
Assistant Professor
Contact information
メールアドレス

Degree 1

  1. 博士(医療技術学) ( 2022.3   名古屋大学 ) 

Research Areas 1

  1. Life Science / Radiological sciences  / 医学物理学

Research History 1

  1. Nagoya University   Assistant Professor

    2022.6

Professional Memberships 4

  1. 日本核医学技術学会

  2. 日本放射線技術学会

  3. 日本分子イメージング学会

  4. 日本医学物理学会

 

Papers 19

  1. Optimization of the energy window setting in Ir-192 source imaging for high-dose-rate brachytherapy using a YAP(Ce) gamma camera Reviewed

    Jura Nagata, Kohei Nakanishi, Seiichi Yamamoto, Takuya Yabe, Katsunori Yogo, Yumiko Noguchi, Kuniyasu Okudaira, Kei Kamada, Akira Yoshikawa, Jun Kataoka

    Physica Medica   Vol. 103   page: 66 - 73   2022.11

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    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)   Publisher:Elsevier BV  

    DOI: 10.1016/j.ejmp.2022.09.017

  2. Monte Carlo approach to comparison of parallel-hole collimators of clinical scintillation camera system for imaging astatine-211 (At-211) Reviewed

    Kohei Nakanishi, Seiichi Yamamoto, Jun Kataoka

    Journal of Instrumentation   Vol. 17 ( 10 ) page: T10007 - T10007   2022.10

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    Authorship:Lead author, Corresponding author   Language:English   Publishing type:Research paper (scientific journal)   Publisher:IOP Publishing  

    Abstract

    Astatine-211 (At-211) is a promising alpha particle emitter for targeted radionuclide therapy. Since its daughter isotope (polonium-211(Po-211)) emits characteristic X-rays of about 80 keV, the distribution of At-211 in the body can be imaged by detecting the X-rays with a scintillation camera. However, the isotopes also emit high-energy gamma photons that are collimated with difficulty for a parallel-hole collimator of a clinical scintillation camera system, and thus the selection of a collimator is important. In this study, we compared the performances of low-energy high-resolution (LEHR), low-energy all-purpose (LEAP), medium-energy (ME), and high-energy (HE) parallel-hole collimators for At-211 using Monte Carlo simulation. We simulated a clinical scintillation camera system with the collimators using the Geant4 toolkit. The energy spectra, sensitivities, and spatial resolutions for the point source of At-211 were evaluated. Moreover, we simulated imaging of six sphere sources of At-211 in a 1-cm-thick cylindrical phantom filled with At-211 solution to evaluate image contrast. All of the results in this study are simulation data. The spatial resolution with LEHR was 7.6 mm full width at half maximum (FWHM) and the highest between collimators, while the sensitivity with LEAP was 85 cps/MBq and the highest. The image contrast acquired with the ME collimator was superior to those with the other collimators. We concluded that the LEHR, LEAP, and ME collimators had their advantages, so an optimum collimator should be selected depending on the purpose of imaging of At-211, although there was no advantage in using the HE collimator for the imaging of At-211.

    DOI: 10.1088/1748-0221/17/10/t10007

    Other Link: https://iopscience.iop.org/article/10.1088/1748-0221/17/10/T10007/pdf

  3. Short‐time sequential high‐energy gamma photon imaging using list‐mode data acquisition system for high‐dose‐rate brachytherapy Reviewed

    Jura Nagata, Seiichi Yamamoto, Takuya Yabe, Katsunori Yogo, Kohei Nakanishi, Yumiko Noguchi, Kuniyasu Okudaira, Kei Kamada, Akira Yoshikawa, Jun Kataoka

    Medical Physics     2022.9

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:Wiley  

    DOI: 10.1002/mp.15957

  4. Trials of transmission imaging using clinically used Ir-192 source for high-dose-rate brachytherapy Reviewed

    J. Nagata, S. Yamamoto, K. Nakanishi, Y. Noguchi, K. Okudaira, J. Kataoka

    Journal of Instrumentation   Vol. 17 ( 06 ) page: T06009 - T06009   2022.6

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:IOP Publishing  

    Abstract

    In high-dose-rate (HDR) brachytherapy, verification of an Ir-192 source's position during treatment is required. One of the methods for this used a high-energy pinhole gamma camera to image the position of the source, but the absolute position of the source cannot be measured. To confirm the absolute position, it will be useful to acquire the transmission image of a subject in addition to the gamma photon image at the same time without using an additional X-ray system. To measure the transmission images, we tried to use the high-energy gamma photons emitted from the Ir-192 source used for the therapy. We developed a high-energy gamma photon imaging system composed of 1-mm-thick Pr doped Gd<sub>2</sub>O<sub>2</sub>S (GOS), a surface mirror, and a cooled charge-coupled device (CCD) camera. The developed imaging system achieved transmission imaging of high-energy gamma photons by transporting the Ir-192 source in front of the imaging system. The spatial resolution of the imaging system was better than 2.4 mm FWHM with and without a 10-cm-thick acrylic block set between the imaging system and the source. Moderate spatial resolution and contrast images of phantoms were obtained with the system. For the dynamic imaging mode, continuous images of the phantoms were measured with 1-sec intervals. There was no observable difference in the transmission images by the movement of the Ir-192 source. Transmission imaging of subjects using an Ir-192 source for HDR brachytherapy could be achieved using our developed imaging system. The system offers a new method to measure the real-time transmission images of the subject during HDR brachytherapy.

    DOI: 10.1088/1748-0221/17/06/t06009

    Other Link: https://iopscience.iop.org/article/10.1088/1748-0221/17/06/T06009/pdf

  5. In-vivo imaging of a mouse by detecting bremsstrahlung X-rays from 14C using a La-GPS imaging system Reviewed

    Seiichi Yamamoto, Hideki Tomita, Ryohei Terabayashi, Kenji Yoshida, Kouhei Nakanishi, Takako Furukawa, Kei Kamada, Akira Yoshikawa

    Journal of Nuclear Science and Technology     page: 1 - 12   2022.3

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:Informa {UK} Limited  

    DOI: 10.1080/00223131.2022.2050319

    Web of Science

    Scopus

  6. Prediction of CT Images from PET Images Using Deep Learning Approach for Small Animal Systems

    Kouhei Nakanishi, Seiichi Yamamoto, Tadashi Watabe

    2021 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC)     2021.10

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    Authorship:Lead author   Language:English   Publishing type:Research paper (international conference proceedings)   Publisher:IEEE  

    DOI: 10.1109/nss/mic44867.2021.9875591

  7. Comparison of the distributions of bremsstrahlung X-rays, Cerenkov light, and annihilation radiations for positron emitters Reviewed

    Kouhei Nakanishi, Seiichi Yamamoto

    Applied Radiation and Isotopes   Vol. 176   page: 109861 - 109861   2021.10

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    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)   Publisher:Elsevier {BV}  

    DOI: 10.1016/j.apradiso.2021.109861

    Web of Science

    Scopus

    PubMed

  8. Monte Carlo study of a small field of view YAlO3:Ce pinhole camera for imaging with Rb-82 by detection of bremsstrahlung X-rays Reviewed

    K. Nakanishi, S. Yamamoto

    Journal of Instrumentation   Vol. 16 ( 08 )   2021.8

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    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)   Publisher:{IOP} Publishing  

    DOI: 10.1088/1748-0221/16/08/t08005

    Web of Science

    Scopus

  9. Performance evaluation of YAlO3 scintillator plates with different Ce concentrations Reviewed

    Kohei Nakanishi, Seiichi Yamamoto, Kei Kamada, Akira Yoshikawa

    Applied Radiation and Isotopes   Vol. 168   page: 109483 - 109483   2021.2

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    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)   Publisher:Elsevier {BV}  

    DOI: 10.1016/j.apradiso.2020.109483

    Scopus

  10. Development of high‐resolution YAP(Ce) x‐ray camera for the imaging of astatine‐211(At‐211) in small animals Reviewed

    Kouhei Nakanishi, Seiichi Yamamoto, Tadashi Watabe, Kazuko Kaneda-Nakashima, Yoshifumi Shirakami, Kazuhiro Ooe, Atsushi Toyoshima, Atsushi Shinohara, Takahiro Teramoto, Jun Hatazawa, Kei Kamada, Akira Yoshikawa

    Medical Physics   Vol. 47 ( 11 ) page: 5739 - 5748   2020.11

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    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)   Publisher:Wiley  

    DOI: 10.1002/mp.14455

    Web of Science

    PubMed

  11. Monte Carlo simulation of the bremsstrahlung X-rays emitted from H-3 and C-14 for the in-vivo imaging of small animals Reviewed

    Kouhei Nakanishi, Seiichi Yamamoto

    Applied Radiation and Isotopes   Vol. 160   page: 109136 - 109136   2020.6

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    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)   Publisher:Elsevier {BV}  

    DOI: 10.1016/j.apradiso.2020.109136

    Web of Science

    PubMed

  12. Imaging of bremsstrahlung X-rays from tritium water in a plastic bag using a LaGPS radiation imaging system Reviewed

    S. Yamamoto, K. Nakanishi, T. Furukawa, H. Tomita, K. Kamada, A. Yoshikawa

    Journal of Instrumentation   Vol. 15 ( 04 ) page: P04006 - P04006   2020.4

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:{IOP} Publishing  

    DOI: 10.1088/1748-0221/15/04/p04006

  13. Feasibility evaluation of a direct detection method of alpha particles in water using YGAG plate with pulse shape analysis Reviewed

    S. Yamamoto, K. Nakanishi, S. Terazawa

    Journal of Instrumentation   Vol. 14 ( 10 ) page: P10013 - P10013   2019.10

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:{IOP} Publishing  

    DOI: 10.1088/1748-0221/14/10/p10013

  14. Comparison of Noise Equivalent Count Rates (NECRs) for the PET Systems With Different Ring Diameter and Electronics Reviewed

    Kouhei Nakanishi, Yoshiyuki Hirano, Seiichi Yamamoto

    IEEE Transactions on Radiation and Plasma Medical Sciences   Vol. 3 ( 3 ) page: 371 - 376   2019.5

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    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)   Publisher:Institute of Electrical and Electronics Engineers ({IEEE})  

    DOI: 10.1109/trpms.2018.2876410

    Web of Science

  15. Possibility analysis of bremsstrahlung x-ray imaging of C-14 radionuclide using a LaGPS radiation imaging system Reviewed

    Seiichi Yamamoto, Kouhei Nakanishi, Takako Furukawa, Hideki Tomita

    Biomedical Physics & Engineering Express   Vol. 5 ( 3 ) page: 035024 - 035024   2019.4

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:{IOP} Publishing  

    DOI: 10.1088/2057-1976/ab12bd

    Web of Science

  16. Development of a circular shape Si-PM-based detector ring for breast-dedicated PET system Reviewed

    Nakanishi, K., Yamamoto, S., Watabe, H., Abe, S., Fujita, N., Kato, K.

    Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment   Vol. 880   page: 118 - 124   2018

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    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1016/j.nima.2017.10.052

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    Scopus

  17. Estimation of optimum scintillator thickness of Si-PM detectors for time-of-flight (TOF)-PET Reviewed International coauthorship

    Kouhei Nakanishi, Kanako Kodani, Jung Yeol Yeom, Seiichi Yamamoto

    Biomedical Physics &amp; Engineering Express   Vol. 3 ( 2 ) page: 027002 - 027002   2017.3

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    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)   Publisher:{IOP} Publishing  

    DOI: 10.1088/2057-1976/aa635e

    Web of Science

  18. Performance comparison of finely pixelated LYSO- and GAGG-based Si-PM gamma cameras for high resolution SPECT Reviewed

    Nakanishi, K., Yamamoto, S., Kataoka, J.

    Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment   Vol. 872   page: 107 - 111   2017

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    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

    Although Lu-based scintillators, including Ce-doped Lu1.8Y0.2SiO5 (LYSO) scintillators, are often used for positron emission tomography (PET) detectors, they are not commonly used in gamma cameras for single-photon emission computed tomography (SPECT) because background counts due to contamination of the natural radioisotope in Lu are detected. However, several studies report that deterioration in image contrast due to background counts of the natural radioisotope is not critical and thus LYSO is promising for use in SPECT detectors. Meanwhile, a new scintillator, the Ce-doped Gd3Al2Ga3O12 (GAGG) with a high light yield and no natural radioisotope, has been developed and is also thought to be a promising scintillator. Thus, we compared the performance of LYSO with that of GAGG to determine which is more appropriate for a silicon photomultiplier (Si-PM)-based high-resolution small field-of-view (FOV) gamma camera for SPECT. We used finely pixelated LYSO and GAGG plates that were optically coupled to Si-PM arrays to form gamma cameras and measured the basic performance for 122-keV gamma photons. The energy resolutions of the LYSO- and GAGG-based Si-PM gamma cameras were 30% and 23% full width at half maximum (FWHM), respectively. The intrinsic spatial resolution of the GAGG (∼0.5mm FWHM) based gamma camera was better than that of the LYSO (∼0.6mm FWHM). The background counts of the LYSO-based gamma camera were 28 times larger than that of the GAGG. Based on these results, we conclude that GAGG is more appropriate than LYSO for the development of a Si-PM based gamma camera for high resolution SPECT.

    DOI: 10.1016/j.nima.2017.08.013

    Web of Science

    Scopus

  19. Development of an angled Si-PM-based detector unit for positron emission mammography (PEM) system Reviewed

    Nakanishi, K., Yamamoto, S.

    Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment   Vol. 837   page: 171 - 177   2016

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    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1016/j.nima.2016.09.014

    Web of Science

    Scopus

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MISC 1

  1. 鉛玉を用いたMRI用不均一磁場補正padの有用性評価—Evaluation of usefulness of pad filled with lead sphere to correct inhomogeneous magnetic field for MRI Reviewed

      Vol. 69 ( 2 ) page: 142 - 149   2022.2

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    Authorship:Lead author, Corresponding author   Language:Japanese   Publishing type:Rapid communication, short report, research note, etc. (scientific journal)  

    CiNii Books