Blein Mulugeta¹, Wondemu Geteye¹, Efrem Mengistu², Yenuse Molla¹, and Ali Beyene¹
¹Department of Medical Radiologic Technology, Addis Ababa University, Ethiopia
²Department of Physics, Dire-Dewa University, Ethiopia

Part of the book: Advances in Health and Disease. Volume 63

Abstract

Computed tomography (CT) has become the most commonly used medical imaging modality and a powerful clinical tool for the diagnosis and management of patients. However, CT is associated with relatively high radiation doses with a corresponding increased risk of carcinogenesis. The optimization of patient protection in CT requires the application of examination-specific scan protocols. A diagnostic reference level (DRL) is a form of investigation level used as a tool to aid in the optimization of protection in the medical exposure of patients for diagnostic and interventional procedures. There are no studies conducted regarding the establishment of DRL on CT in Addis Ababa, Ethiopia. As a result, the purpose of this study was to establish a local diagnostic reference level and estimation of an effective dose for adult CT in Addis Ababa, Ethiopia. A cross-sectional facility-based study design was used to conduct this prospective study. Common adult CT examinations of the head, chest, and abdomen-pelvic without contrast in five CT centers from December 20, 2019, to March 10, 2020, were studied. A total of 430 patient data was collected. Obtained data were analyzed by descriptive statistics using SPSS version 21.0. The established local diagnostic reference level (LDRL) of the head, chest, and abdominopelvic in dose quantities of Volume Weighted Computed Tomography Dose Index (CTDIvol)(mGy) and dose length product (DLP) (mGy.cm) were 51mGy, 1246 mGy.cm; 11.18mGy, 400mGy.cm and 11.96mGy, 612.59 mGy.cm respectively. The estimated effective dose for head, chest, and abdomen pelvic were 2.6mSv, 5.6mSv, and 9.2mSv respectively. The head DLP and effective dose value were above the recommended value. The scan length and scan protocol used for head scan in the surveyed center was high.

Keywords: CT, CTDIvol (mGy), DLP (mGy.cm), LDRLs

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