Radiation protection has to be considered when CT examinations are being performed. Careful assessment of the X-ray dosage needed for CT examinations is necessary. The International Commission on Radiological Protection (ICRP 1977) went on to stress “justification” of the procedure’s dosage related to the benefits, costs, and risks that are a consequence of CT examination, and that minimum X-ray exposure doses should be used when undertaking tomographical procedures. Undesirable effects that result even from low X-ray doses must be considered, and acceptable dose levels should be established. Radiation risks in relation to clinical benefits have to be carefully assessed. Yoshizawa et al. (1979) estimated the risks for each CT examination of the thoracic and abdominal part of the body for males and females. His research revealed that each examination carried the following probabilities: genetically harmful effects, 4.8 × 10−7; leukemia, 4.8 × 10−6; pulmonary cancer, 1.6 × 10−5; thyroid cancer, 1.8 × 10−7; and mammary cancer, 1.8 × 10−5. Similar studies were carried out by Löhr et al. (1980), and agree that physicians who conduct CT examinations should know and minimize the X-ray doses they intend to use.
KeywordsDose Distribution Exposure Dose Surface Dose Skin Entrance Dose Leakage Radiation
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