Celebrate the Power of Imaging: the European Day of Radiology

examinations are performed every year in Belgium. With a mean dose 0,5 mSv, the annual collective dose from CT could induce up to 450 cancer. This number has to be compared to the 45 000 observed new cancers yearly. The deleterious effect of scanner radiation is thus undetectable among cancers induced by smoking, alcohol, and western diet. Risk from radiation is based on cancer mortality rates observed among atomic bomb survivors who underwent high level radiation. Overestimation of collective radiation risks in the filed of low level radiation (below 0,2 Sv) as used for CT is suspected first because a majority of patients undergoing CT are aged 60 years or more, and second because the numerous defense mechanisms that prevent cancer induction at lowdoses in human bodies are not taken into account by the linear no threshold model of carcinogenesis used as legal rule for risk calculations. On the other hand, CTis a rapid and efficient technique that providesaccurate diagnosis of various disorders such as acute appendicitis complete staging of severely injured patients, reliable monitoring of tumors and therapy guidance or planning. CT yields very high confidence in diagnosis that is required for treatment. The balance between radiation risk from CT and clinical benefit is thus almost always very high. However, because of its success and performance, overuse of CT is suspected. This overuse has been addressed by RIZIV / INAMI When a CT is performed, according to guidelines, radiologists are in duty of limiting the delivered radiation dose by optimizing the CT technique. This is the practical application of the ALARA principle (As Low As Reasonably Achievable). The process of optimization is under the control of the Federal Agency for Nuclear Control (FANC/AFCN). The method for dose limitation is based on surveys. With the collaboration in collabo ration with the Consilium Radiologicum. Objective is to promote guidelines for an appropriate use of medical imaging tests and to reduce the rate of unjustified examinations. The expected effect should be a collective dose reduction but also financial. JBR–BTR, 2011, 94: 100-102.