Sara Khosravi - School of Allied Medical Sciences, Shahroud University of Medical Sciences, Shahrood, Iran
Mahsa Sadeghi - School of Allied Medical Sciences, Shahroud University of Medical Sciences, Shahrood, Iran
Golshan Mahmoudi - School of Allied Medical Sciences, Shahroud University of Medical Sciences, Shahrood, Iran

Abstract: Introduction: COVID-۱۹ is a severe acute respiratory syndrome that has rapidly spread with a significant global outbreak. The gold standard for the diagnosis of COVID-۱۹ is RT-PCR tests that have a varied sensitivity within the range of ۶۰-۹۵%. Several studies showed that the chest CT scan plays an important role in detecting COVID-۱۹ with a sensitivity of around ۹۷%. However, several international institutes stated that a CT scan should not be used as a first-line test to diagnose COVID-۱۹ due to its harmful side effects, especially cancer risk. We aimed to evaluate the rate of normal chest CT scans for COVID-۱۹ detection in Shahroud and estimate the cancer incidence risk associated with these normal CT scans .Materials and Methods: In total, the data of ۵۶۴ patients referred to the radiology center of two hospitals in Shahroud were collected. CT scan reports were categorized into three groups according to the interpretation of the radiologist: score ۰, had no pathological findings representing normal CT scans; score ۱, had suspicious findings representing potentially abnormal CT scans, and score ۲, had confirmed pathological findings representing abnormal CT scans. The BEIR VII model was used to estimate the radiation cancer risk .Results: Among the ۵۶۴ patients, ۳۰۱ (۵۳.۳۷%) were males and the average age of the patients was ۴۹.۶۲ ± ۱۸.۶۹ years. CT scans in ۴۰۸ (۷۲.۷۳%) cases were reported normal. The average age of the patients with normal, abnormal, and potentially abnormal CT scans was ۴۷.۵۷±۱۹.۰۶, ۵۴.۸۰±۱۶.۷۰, and ۵۸.۱۴±۱۶.۶۰ years, respectively, and the differences were statistically significant (p-value <۰.۰۰۱). The average effective dose was obtained ۱.۵۶±۰.۷ for age groups of >۱۰-year-old. The average risk of lung cancer was۱.۴۹±۰.۷۸ and ۳.۳۰±۱.۲۰ per ۱۰۰,۰۰۰ patients for males and females, respectively. Cancer risk for all types of cancers was ۹.۱۱±۵.۱۰ and ۱۲.۳۲±۹.۰۱ for males and females, respectively

COVID-۱۹, radiation cancer risk, CT scan