If you are exposed for the purpose of medical care, limit the amount of exposure is not legally defined. This is because it is judged to outweigh the disadvantages benefit from diagnosis and treatment to exposure. However, it is necessary to be performed exposure becomes a minimum. Radiotherapy is intended to be made for the treatment of illness and specific, it means side effects that medical exposure is associated with it.
Radiotherapy should not be compared on the same level and exposure of other, as it is to consider the benefits of obtaining the disease's treatment-harm (risk), is subjected to medical personnel is determined to benefit. However it is in hindsight, only that it is safe and health damage that is exposed when it is diagnosed health diagnostic radiation is left. In diagnostic radiology in Prevention and Screening, guidelines that takes into account the risk of exposure is set.
Effective dose of medical exposure is greater than exposure from natural radiation in the medical some developed countries, including Japan with the spread progress and diagnostic radiation, the radiation therapy. According to the report of 2008 on the effects of Atomic Radiation United Nations Scientific Committee (UNSCEAR), 13.8 million times in 1988, radiation diagnosis in all the world was 0.35mSv average dose http://marklester.co.uk/ear-defenders-for-babies-baby-protection/ per person, but in 2008 to 31 million times, average dose became 0.62mSv.
The average medical developed countries has become a 1.92mSv but 2.3mSv [5], the United States has been estimated 3.0mSv [6] in Japan. During the 1991-1996 year was 4.7 million times per year with respect to radiation therapy, but it has increased to 5.1 million times between 1997 and 2007. Treatment with a linear accelerator also has been increasing. Radiation therapy has become (the world average is 0.8 times) and 2.4 times per year one thousand people per medical developed countries, the frequency continues to increase.
Penetration of CT equipment protrudes from other countries in Japan, 92.6 units per one million people population (2002), in Australia 45.3 units (2004), 32.3 units 3rd America 2 position met (2004) were. There is a medical exposure of 0.6-2.7mSv in X-ray inspection 6.9mSv, the stomach just receive once the CT is possible with the height of this penetration, be examined easily speaking bad easily.
Chest 0.04mSv, abdominal 1.2mSv, upper gastrointestinal tract 8.7mSv, chest CT 7.8mSv, exposure dose of X-ray inspection typical in Radiology is a abdominal CT 7.6mSv. It should be noted that the dose of a single whole body irradiation, which is performed for bone marrow transplantation in 2,000mSv, conducted three days of irradiation twice a day, I is irradiated with 12,000mSv in total. In stereotactic radiation therapy for lung cancer have to end in a week was irradiated five times from 4 times a large dose of once 10,000mSv or more