Hokkaido University Research Profiles

Life Sciences

Development of a Compact Dosimeter Using an Optical Fiber

Application of ultra-small dosimeters to radiotherapy and diagnostic fields by combining an ultra-small scintillator and an optical fiber

In recent years, there has been increasing interest in radiation protection against serious skin damage caused by X-ray fluoroscopy. Through this research, we developed a plain ultra-small plastic scintillator dosimeter that does not show up on X-ray fluoroscopic images attached to the end of the optical fiber to prevent late-onset radiation injury.

Content of research

For endovascular treatment with X-ray fluoroscopy (IVR; Interventional Radiology), the patient is subjected to prolonged X-ray fluoroscopy. Repeated procedures for myocardial infarction and other conditions may cause ulcers and other serious skin disorders. Conventional dosimeters have the problem that they cause a shadow in the fluoroscopy detection area. In particular, since energy dependence affects the accuracy of measurements, there have been no dosimeters that are compact, have little energy dependence, and do not cause shadows on fluoroscopy. However, the SOF dosimeter developed in this study is characterized by not showing up under X-ray fluoroscopy because the density of the sensor part is close to that of the living body. At present, the SOF dosimeter has achieved sensitivity variation of 5% or less in a range of 60 to 150 kV, and we are working with a company to improve the sensor material to further reduce the sensitivity variation.

Potential for social implementation

  • ・Angiography equipment
  • ・X-ray tomography system (CT system)
  • ・General radiography equipment (e.g., chest radiography, continuous abdominal radiography)
  • ・Sealed small source therapy

Appealing points to industry and local governments

For medical applications such as diagnostic X-rays, the product is already sold under the name MIDSOF, and its basic technology has been established. Since it is compact and does not show up on fluoroscopy, we believe that it has a very wide range of applications. We would like to actively conduct joint research on the development of applied products using this technology.

Intellectual property related to this research

PCT/JP 2007/68675 「放射線線量計および放射線線量計算プログラム
(日本:特許第4766407号  米国:特許8,044,357号  欧州:07807890.4)