Mika Kortesniemi’s research while affiliated with Helsinki University Central Hospital and other places

As in any medical intervention, there is either a known or an anticipated benefit to the patient from undergoing a medical imaging procedure. This benefit is generally significant as demonstrated by the manner in which medical imaging has transformed clinical medicine. At the same time, when it comes to imaging that deploys ionizing radiation, there is a potential associated risk from radiation. Radiation risk has been recognized as a key liability in the practice of medical imaging, creating a motivation for radiation dose optimization. The level of radiation dose and risk in imaging is varied but is generally low. Thus, from epidemiological perspective, this makes the estimation of the precise level of associated risk highly uncertain. However, in spite of the low magnitude and high uncertainty of this risk, its possibility cannot be easily refuted. Therefore, given the moral obligation of healthcare providers, "first do no harm," there is an ethical obligation to mitigate this risk. How to precisely achieve this goal scientifically and practically within a coherent system has been lacking. To address this need, in 2016, the International Atomic Energy Agency (IAEA) organized a summit to clarify the role of Diagnostic Reference Levels to optimize imaging dose [1,2], summarized into an initial report [3]. Through a consensus building exercise, the summit further concluded that the imaging optimization goal goes beyond dose alone, and should include image quality as a means to include both the benefit and the safety of the exam. The present, second report details the deliberation of the summit on imaging optimization.