Abstract
Medical use of radiation is firmly established as an essential tool for diagnosis and therapy. On the other hand, it has accounted for the biggest rate in radiation exposure of the human beings by the source of artificial radiation. It is approved that the overwhelming benefit accruing to patients from general medical use of radiation compared with a risk. However, it is also a fact that it occasionally has the difference in one 10 the dose of this by the irradiation part, conditions, and the model of equipment even if the same purpose irradiation. In many cases, individual dose of patient by X ray examination is performed below with a few mGy. However CT bring about a high dose more in individual dose and collective doses. And, the skin dose of the individual by IVR to which diagnosis and medical treatment are performed simultaneously exceeds several Gy. Even if it is medical exposure, unnecessary exposure should avoid and judgment of justification and optimization is desired for every case. Moreover, rapid introduction of a reference dose is required to examination that almost fixed method.
