Estimation Risk of Exposure-induced Death Associated with Common Computed Tomography Procedures During the COVID-19 in Yazd Province


1 Department of Medical Physics School of Medicine, Tabriz University of Medical Science, Tabriz, Iran

2 Department of Medical Physics Faculty of Medicine, Shahid Sadoughi University of Medical Sciences, Yazd, Iran

3 Tabriz University of Medical Sciences

4 Department of Medical Physics School of Medicine Tabriz University of Medical Science, Tabriz, Iran*



During the last decade, the increasing frequency of CT scans for a range of purposes, particularly pediatrics, has raised concerns regarding the population radiation exposure and subsequent chances of cancers. This study aimed to estimate the pediatrics radiation exposure from the five most common CT scans during the COVID-19 whitten three recent years in Yazd Province and to present a more tangible form of the doses by giving the risk of exposure-induced cancer death (REID) due to the performed CT scans. Methods: The risk of exposure-induced death (REID) was calculated by coupling the BEIR VII model and ICRP 103 data for the Asian population. Results. Data of patients younger than 15 years of age and adult age group were retrospectively collected from 6 educational institutions located in diverse areas of Yazd Province.
The median effective doses for the five most common procedures, in adult group, were as follows: 5.20 mSv for abdomen-pelvis, 3.31 mSv for routine chest, 3.00 mSv for chest HRCT, 0.76 mSv for Brain and 0.48 mSv for sinus. The highest associated risk was tied to high-resolution CT scans for women which was estimated to be 1 exposure-induced death related to 2097 scans performed on a 20-year old patient. The highest mean effective dose for younger than 15 years was estimated for the scan of abdomen-pelvis (average, 5.24 mSv) followed by chest (average, 3.66 mSv), brain (average, 1.27 mSv), and sinus (average, 0.65 mSv) scan. Moreover, the highest REID was documented for chest scan (average, 490 excess deaths in a million scans) followed by abdomen-pelvis procedure (average, 404).
Although theeffectivedoseofCTprocedures in Yazd Province increased continuously, they were comparably lower than those reported for other countries. The radiation doses and cancer risks arising from pediatric CT scans are comparable with analogous studies, yet occurrence of high variation among patients of specific subcategorization which indicates the need for further optimization. Nevertheles, findings can represent an estimation of the hazards from CT scans for the purpose of extending the knowledge of physicians as well as those who are in charge of such procedures. Keywords: computed tomography; Cancer risk estimation; Radiation Exposure; COVID-19 FUNDING
This work was supported by Shahid Sadoughi University of Medical Sciences and Health Services. (grant number: 6627 and ethical committee consent number: IR.SSU. REC.1399.067)