Department of Medical Equipment Engineering, Clinical Collaboration Unit,
Faculty of Radiological Technology, Fujita Health University


The "Department of Medical Equipment Engineering", which belongs to the Clinical Collaboration Unit of the Faculty of Medical Science, promotes clinical research and education in collaboration with the Department of Radiology, University Hospital. Through this collaboration, we will teach real-time medical care in university education. In this field, we aim to develop radiological technologists who have acquired research capabilities by conducting basics of medical imaging equipment (Monte Carlo simulation) and clinical research.


Faculty members

Radiological Technology

Research Theme

1. Nonuniform sampling pitch acquisition method in myocardial single-photon emission computed tomography
2. Development of a Noise Removal Method Using Deep Learning for SPECT Projection Images

Single photon emission computed tomography (SPECT) affects image quality due to attenuation, scattered radiation, resolution degradation, statistical noise, etc. We are developing a method to correct attenuation, scattered radiation, and resolution deterioration at the same time as image reconstruction by incorporating Monte Carlo simulation into the successive approximation image reconstruction method. We will also pursue faster processing time and aim for clinical use. On the other hand, for statistical noise removal, we have developed a method using deep learning. In the future, we will work on further research on its clinical application and image generation by deep learning. (Seiji Shirakawa)

(A) is an ideal image (no noise) with sufficient counts collected, and an image in which the effect of resolution deterioration (b), the effect of attenuation (c), and the effect of scattered radiation (d) are added to this image.

1. Research on medical exposure and radiation protection
2. Development of digital teaching materials and digital phantoms

Exposure to radiation cannot be avoided during diagnostic imaging. The International Commission on Radiological Protection (ICRP) has reported that there is room for reduction of medical exposure doses. In order to create a safe environment for diagnostic radiological imaging, we are planning and carrying out a wide range of research themes, such as proposing methods for evaluating and reducing medical exposure using actual measurements and Monte Carlo simulations, and developing dosimetry software and digital phantoms. In recent years, we have also been actively pursuing challenging research that meets the needs of the times, such as the development of educational materials using digital devices such as projection mapping, computer graphics, virtual reality, and motion capture.(Masanao Kobayashi)

Academic Activities



  • Masakazu Tsujimoto, Seiji Shirakawa, Masanori Watanabe, Atsushi Teramoto, Masaki Uno, Seiichiro Ota, Ryo Matsukiyo, Taro Okui, Yoshikazu Kobayashi, Hiroshi Toyama Two-versus three-dimensional regions of interest for quantifying SPECT-CT images Physical and Engineering Sciences in Medicine. 44(2): 365-375, 2021
  • Koichi Okuda, Hiroki Nosaka, Toshimune Ito, Norikazu Matsutomo, Hajime Ichikawa, Seiji Shirakawa, Noriyasu Yamaki, Akihiro Kikuchi, Hiroyuki Tsushima, Michael Ljungberg Validation of Simulation Codes for Nuclear Imaging Using Digital Phantoms. Nihon Hoshasen Gijutsu Gakkai Zasshi. 77(1):41-47, 2021
  • Yuta Matsunaga, Tomonobu Haba, Masanao Kobayashi, Shoichi Suzuki, Yasuki Asada, Koichi Chida. Novel pregnant model phantoms for measurement of foetal radiation dose in x-ray examinations. Journal of Radiological Protection 41(3) N12-N21 2021.
  • Yoshikazu Kobayashi, Masanao Kobayashi, Daisuke Kanamori, Naoko Fujii, Yumi Kataoka, Koji Satoh, Yoshimi Sano, Satoshi Yoshioka, Ichiro Tateya, Hiroshi Toyama, Koichiro Matsuo. Evaluation of Velopharyngeal Closure Function With 4-Dimensional Computed Tomography and Assessment of Radiation Exposure in Pediatric Patients: A Cross-Sectional Study. The Cleft palate-craniofacial journal : official publication of the American Cleft Palate Craiofacial Association 10556656211001732-10556656211001732 2021.
  • Yuta Matsunaga, Tomonobu Haba, Masanao Kobayashi, Shoichi Suzuki, Yasuki Asada, Koichi Chida. Fetal radiation dose of four tube voltages in abdominal CT examinations during pregnancy: A phantom study. Journal of applied clinical medical physics 22(2) 178-184 2021.
  • Tomonobu Haba, Keisuke Yasui, Yasunori Saito, Masanao Kobayashi, Shuji Koyama. A new cone-beam computed tomography dosimetry method providing optimal measurement positions: A Monte Carlo study. European Journal of Medical Physics 81 130-140 2021.


  • Kosuke Matsubara, Hiroki Kawashima, Masanao Kobayashi, Atsushi Fukuda. Performance evaluation of near-real time angular tube current modulation in X-ray computed tomography using real-time dosimeter: a phantom study. Health and Technology 10(6) 1437-1443 2020.
  • Yoshikazu Kobayashi, Masanao Kobayashi, Daisuke Kanamori, Naoko Fujii, Yumi Kataoka, Koji Satoh, Yoshimi Sano, Satoshi Yoshioka, Ichiro Tateya, Hiroshi Toyama, Koichiro Matsuo. Early experience with four-dimensional computed tomography for observing velopharyngeal closure function in pediatric patients and the evaluation of the exposure dose. Research Square 2020.
  • Yasuki Asada, Yuya Kondo, Masanao Kobayashi, Kenichi Kobayashi, Takuma Ichikawa, Yuta Matsunaga. Proposed diagnostic reference levels for general radiography and mammography in Japan. Journal of radiological protection : official journal of the Society for Radiological Protection 40(3) 867-876 2020.
  • Yuta Matsunaga, Yuya Kondo, Kenichi Kobayashi, Masanao Kobayashi, Kazuyuki Minami, Shoichi Suzuki, Koichi Chida, Yasuki Asada. VOLUME CT DOSE INDEX AND DOSE-LENGTH PRODUCT VALUES ACCORDING TO FACILITY SIZE IN JAPAN. Radiation protection dosimetry 188(2) 261-269 2020.
  • Tokiko Nakamura, Suzuki Shoichi, Yasutaka Takei, Masanao Kobayashi, Vergil Cruz, Ikuo Kobayashi, Satoshi Asegawa, Kyoichi Kato. A more accurate and safer method for the measurement of scattered radiation in X-ray examination rooms. Radiological physics and technology 13(1) 69-75 2020.
  • Masanao Kobayashi, Tomonobu Haba, Sayaka Suzuki, Yusei Nishihara, Yasuki Asada, Kazuyuki Minami. Evaluation of Exposure Dose in Fetal Computed Tomography Using Organ-Effective Modulation. Physical and Engineering Sciences in Medicine 43(4) 1195-1206 2020.


  • Seiji Shirakawa, Kei Tsukamoto, Hiroyuki Azuma, Kazutaka Nakashima, Masakazu Tsujimoto, Kazuki Takano, Masayuki Yamada. Nonuniform Sampling Pitch Acquisition Method in Myocardial Single-Photon Emission Computed Tomography. Nuclear Medicine Communications. 40(8): 792-801, 2019
  • Masanao Kobayashi, Yasuki Asada, Tomonobu Haba, Yuta Matsunaga, Kosuke Matsubara, Kazuyuki Minami. OPTIMISATION OF SWALLOWING CT EXAMINATION: DOSE REDUCTION AND IMAGE QUALITY. Radiation protection dosimetry 185(4) 421-431 2019.
  • Tomonobu Haba, Masanao Kobayashi, Shuji Koyama. Size-specific dose estimates for various weighting factors of CTDI equation. Australasian physical & engineering sciences in medicine 2019 Dec 6. doi: 10.1007/s13246-019-00830-w. Online ahead of print.
  • Kazuyuki Minami, Toshiyuki Ishida, Yasuki Asada, Seiji Shirakawa, Masanao Kobayashi, Shoichi Suzuki, Tomimasa Konishi, Hidenori Mimura. Development of a small X-ray source using an ultraviolet laser and pyroelectric crystal. Wiley Online Library 2019 DOI: 10.1002/xrs.3104.
  • Yuta Matsunaga, Koichi Chida, Yuya Kondo, Kenichi Kobayashi, Masanao Kobayashi, Kazuyuki Minami, Shoichi Suzuki, Yasuki Asada. Diagnostic reference levels and achievable doses for common computed tomography examinations: Results from the Japanese nationwide dose survey. The British journal of radiology 92(1094) 20180290-20180290 2019.


  • Seiji Shirakawa : Programming in the Field of Nuclear Medicine. Nihon Hoshasen Gijutsu Gakkai Zasshi. 77(1): 51-58,2021


  • Access to Medical Equipment Engineering
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