Is it necessary to define new diagnostic reference levels during pandemics like the Covid19-?. (April 2023)

• Record Type: Journal Article
• Authors: Zeinali-Rafsanjani, Banafsheh; Alavi, Azamalsadat; Lotfi, Mehrzad; Haseli, Sara; Saeedi-Moghadam, Mahdi; Moradpour, Moein
• Is Part Of: Radiation physics and chemistry. Volume 205(2023)
• Publication Date: 2023-04
• Subjects: Cumulative effective dose -- Chest CT scan -- Additional cancer risk -- Diagnostic reference level; Radiation chemistry -- Periodicals; Radiometry -- Periodicals; Radiation -- Periodicals; Chimie sous rayonnement -- Périodiques; 539.2
• DOI: 10.1016/j.radphyschem.2022.110739
• Languages: English
• ISSNs: 0969-806X

Abstract

Abstract: Introduction: This study intended to assess the dose length product (DLP), effective cumulative radiation dose (E.D.), and additional cancer risk (ACR) due to a chest CT scan to detect or follow up the Covid-19 disease in four university-affiliated hospitals that used different imaging protocols. Indeed, this study aimed to examine the differences in decision-making between different imaging centers in choosing chest CT imaging protocols during the pandemic, and to assess whether a new diagnostic reference level (DRL) is needed in pandemic situations. Methods: This retrospective study assessed the E.D. of all chest imagings for Covid-19 for six months in four different hospitals in our country. Imaging parameters and DLP (mGy.cm) were recorded. The E.D.s and ACRs from chest CT scans were calculated using an online calculator. Results: Thousand-six hundred patients were included in the study. The mean cumulative dose due to chest CT was 3.97 mSv which might cause 2.59 × 10 −2 ACR. The mean cumulative E.D. in different hospitals was in the range of 1.96–9.51 mSv. Conclusions: The variety of mean E.D.s shows that different hospitals used different imaging protocols. Since there is no defined DRL in the pandemic, some centers use routine protocols, and others try to reduce the dose but insufficiently. In pandemics such as Covid-19, when CT scan is used for screening or follow-up, DLPs can be significantly lower than in normal situations. Therefore, international regularized organizations such as the international atomic energy agency (IAEA) or the international commission on radiological protection (IRCP) should provide new DRL ranges. Highlights: During Covid-19, CT scan has a significant role in screening and follow-up. The mean cumulative dose (ED) of chest CT for Covid-19 patients was 3.969 mSv. 3.969 mSv (range 1.96–9.51 mSv) might cause 2.59 × 10 −2 additional cancer risk. The variety of mean EDs shows different policies in determining imaging protocols. In pandemics, DLPs can be set significantly lower than in normal situations.