What can be done to reduce radiation risk during the performance of a diagnostic procedure?
The most powerful tool for minimising the risk is appropriate performance of the test and optimisation of radiological protection of the patient. These are the responsibility of the radiologist or nuclear medicine physician and medical physicist The basic principle of patients’ protection in radiological X-ray investigations and nuclear medicine diagnostics is that necessary diagnostic information of clinically satisfactory quality should be obtained at the expense of a dose as low as reasonably achievable, taking into account social and financial factors. Evidence obtained in numerous countries indicates that the range of entrance doses (i.e. doses measured at surface of the body at the site where X-ray beam is entering the body) for a given type of radiographic examination is very wide. Sometimes the lowest and highest doses, measured in individual radiological installations, vary by a factor of ~ 100. As most measured doses tend to group at the lower end of the distribution (fig. 4
