Application of the new ICRP 2022 recommendations in calculating radiation risks of patients after computed tomography

The highest doses of medical diagnostic radiation exposure to patients in Russia are caused by computed tomography (CT) procedures, so it is for CT that the control of radiation risks is the most relevant. The main methodology of radiation risk assessment used so far was outlined in the recommendations of the International Commission on Radiological Protection (ICRP) in 2007 (Publication 103). New ICRP recommendations for radiation risk assessment were published in 2022 (Publication 152). The aim of this paper is to compare the radiation risks of malignant neoplasms (MNP) calculated with the use of the ICRP Publication 103 and ICRP Publication 152 models for patients who have undergone one or more different CT procedures. Thoracic CT, pelvic CT, and shoulder girdle CT were selected as examples of calculations. For most organs and tissues, the radiation risk estimates for MNP according to the new ICRP 2022 recommendations are higher than those made according to the past ICRP 2007 recommendations. When a patient underwent a single CT (chest) procedure, the differences in radiation risk estimates for solid MNP were almost insignificant and did not exceed 2%. With several different CT procedures during the patient's lifetime, the differences were as high as 10%. Differences in estimates of radiation risks of leukaemia are more significant. In this study, for a single CT procedure, the increase in radiation risk of leukaemia when switching to the new recommendations reached 53%, but for the studied series of different CT procedures, radiation risks of leukaemia decreased by 9% when changing the model. The results obtained should be taken into account when developing new methods for assessing radiation risks of MND caused by diagnostic irradiation of patients.