Radiology and Nuclear Medicine

Nuclear Medicine

  • Professor: Hiroki Shirato*
  • Associate Professor: Tohru Shiga
  • Specially Appointed Assistant Professor: Kenji Hirata
  • Specially Appointed Assistant Professor: Osamu Manabe
  • Phone: +81-11-706-5152
  • FAX: +81-11-706-7155
  • *concurrent
What is a nuclear medicine?
Nuclear medicine is a new field in medicine for molecular imaging and a therapy using radioisotopes. It provides functional images with additional information over conventional morphologic images such as ultrasound, CT, and MRI.
Positron emission tomography (PET) is an advanced technology using specific radiolabelled compounds as molecular probes for quantifying physiological and biochemical processes. Since specific radiolabelled compounds accumulate in targeted tissues, nuclear medicine is used for cancer treatments as well using large doses of radioisotopes. This treatment is widely applied for thyroid cancer with I-131. Recently, I-131 MIBG has been used for malignant pheochromcytoma and various neuroendocrine tumors.


We are focusing on development of advanced nuclear imaging techniques using PET. The specific research topics and heads of each research groups are as follows:

Nuclear Oncology: Shozo Okamoto, MD, PhD
“Oncology group” has basic science, clinical diagnosis, and radioisotope therapy. In basic science, we are conducting many experiments and are using a micro PET-CT system. In clinical practice, we have 5000 diagnostic imagings in each year.

Brain Imaging : Tohru Shiga, MD, PhD
Research Topics
·Cerebral metabolism and benzodiazepine receptor density imaging.
·Hypoxia and acid metabolism in brain tumor.
·Cerebral blood flow and metabolism in stroke.

Nuclear Cardiology : Keiichiro Yoshinaga, MD, PhD,FACC
We are focusing on myocardial blood flow (MBF), metabolism, and sympathetic nervous function estimation using cardiac PET.

Drug development : Yuji Kuge, PhD

Nuclear physics : Chietsugu Katoh,MD,
Ongoing research topics
·Performance estimation of Micro PET/SPECT/CT.
·Quantification of MBF using 0.15 water and Rubudium-82
·Basic research with semiconductor PET.


International training program
Ken Herrmann, MD (Department of Nuclear Medicine, Technische Universität München) : Japanese-German Radiological Affiliation, PET in oncology and nuclear cardiology .

Ran Klein, PhD (University of Ottawa Heart Institute) : Natural Sciences and Enginneering Research Council of Canada(NSERC)—Japan Society for the Promotion of Science(JSPS) Summer Programs, Nuclear Cardiology, Physics, engineering.
Our collaboration with the University of Ottawa Heart Institute has been expanded this summer through a visit by Ran Klein, a PhD student that is developing cardiac PET image analysis. Ran participated in the JSPS Summer Program. Ran spent 2 months at Department of Nuclear Medicine conducting a comparative study between different image analysis techniques.
Ran states: “My time in Hokkaido was educational and extremely beneficial to my research. Hokkaido′s unique expertise in nuclear medicine has opened my eyes to water imaging, new approaches for image analysis, and most importantly to a different work culture. I am confident that our collaboration will flourish in the years to come–leading to sharing of ideas and research projects that could not be carried out by each of the centers individually.”

International Activities

We have conducted international symposiums. Many top nuclear scientists around the world have visited Sapporo. They have given many lectures and have had intensive discussions with our research groups.
A list of recent guests and the topics:
1.International Nuclear Medicine Special Seminar, 2007
·PA Kaufmann, MD (Zurich University Hospital).
·H Kobayashi, MD (National Cancer Insitute, USA).
·R Pettigrew, MD (National Institute of Biomedical Imaging and Bioengineering, USA).
3.International Nuclear Medicine Special Seminar, 2006
·C Cousins, MD (Addenbrooke's Hospital, UK).
·D Dutka, MD (Addenbrooke's Hospital, UK).
4.Sapporo city Nuclear Cardiology Research Meeting. 2006
·RSB Beanlanlds, MD (University of Ottawa Heart Institute)
1 Lab members at pancake party with Prof. Tamaki.
2 Positron emission tomography scanner
3 Looking into nuclear images at nuclear reporting room

Selected Publications

1. Magota K, Kubo N, Kuge Y, Nishijima K, Zhao S, Tamaki N: Performance characterization of the Inveon preclinical small-animal PET/SPECT/CT system for multimodality imaging.Eur J Nucl Med Mol Imaging 38(4):742-752,2011
2. Hirata K, Kuge Y, Yokota C, Harada A, Kokame K, Inoue H, Kawashima H, Hanzawa H, Shono Y, Saji H, Minematsu K, Tamaki N: Gene and protein analysis of brain derived neurotrophic factor expression in relation to neurological recovery induced by an enriched environment in a rat stroke model.Neuroscience Letters 495(3):210-215,2011
3. Yoshinaga K, Manabe O, Katoh C, Chen L, Klein R, Naya M, Dekemp RA, Williams K, Beanlands RS, Tamaki N: Quantitative analysis of coronary endothelial function with generator-produced 82Rb PET: comparison with 15O-labelled water PET.Eur J Nucl Med Mol Imaging 37(12): 2233-2241, 2010
4. Manabe O, Yoshinaga K, Katoh C, Naya M, deKemp RA, Tamaki N: Repeatability of rest and hyperemic myocardial blood flow measurements with 82Rb dynamic PET. J Nucl Med 50(1): 68-71, 2009
5. Shiga T, Morimoto Y, Kubo N, Katoh N, Katoh C, Takeuchi W, Usui R, Hirata K, Kojima S, Umegaki K, Shirato H, Tamaki N: A new PET scanner with semiconductor detectors enables better indentification of intratumoral ihomogeneity. J Nucl Med 50(1): 148-155, 2009
6. Naya M, Tsukamoto T, Morita K, Katoh C, Nishijima K, Komatsu H, Yamada S, Kuge Y, Tamaki N, Tsutsui H: Myocardial beta-adrenergic receptor density assessed by 11C-CGP12177 PET predicts improvement of cardiac function after carvedilol treatment in patients with idiopathic dilated cardiomyopathy. J Nucl Med 50(2): 220-225, 2009