We developed the pinhole camera system which can image pick-up both radiations and visible light simultaneously. Using the system, we can image pick-up both scattered X-rays from the fluoroscopy equipment directly on an imaging plate. It also enables to image pick-up visible light on printing paper simultaneously. By the superimposed image with these scattered X-rays and visible light, we can get the information about both the source and the direction of scattered X-rays that could not be measured by the conventional methods.
In parallel with the increase in the number of institutions having PET facilities, the number of nurse working in these facilities has also increased, and the issue of occupational radiation exposure has assumed ever greater importance. In our clinic, since nurses have started to administer FDG intravenous injections, their annual radiation exposure has amounted to 4.8-7.1 mSv. To reduce their annual radiation exposure to less than 5 mSv, we identified sources of increased exposure and considered countermeasures based on this information. By implementing countermeasures such as improvements in daily working conditions and ways to avoid various troubles, it was possible to reduce the annual radiation exposure of all nurses to less than 5 mSv. Our experience demonstrates that to provide a working environment with a minimum of occupational radiation exposure, educational training and enhancement of knowledge and technical skills are vital.