Establishing Diagnostic Reference Levels and Radiation Dose for Pediatric Head Age-Based Using Computed Tomography in Khartoum State

Abstract

Computed tomography (CT) is a powerful clinical tool for the diagnosis and management of patients, enabling faster and more accurate diagnosis and the avoidance of interventional surgical techniques. A diagnostic reference level (DRL) is a tool used to aid in optimization of protection in the medical exposure of patients for diagnostic and interventional procedures. It is used in medical imaging with ionizing radiation to indicate whether, in routine conditions, the patient dose or administered activity (amount of radioactive material) from a specified procedure is unusually high or low for that procedure. Radiation dosage variance is one of the topics that arise when dealing with CT devices within medical imaging centers. Diagnostic reference levels have not been established in Sudan. The aim of this study is to propose DRLs for CT of the head for 4 pediatric age groups. The 2 levels that this study covers are volume CT dose index based on a 16-cm phantom (CTDIvol [mGy]) and the dose-length products (DLPs [mGy • cm]). These levels were investigated by conducting a survey to 6 healthcare facilities. The survey consists of questions focused on pediatric exposure parameters, CT protocols, and radiation doses for pediatric age groups <1, 1-5, 5-10, and 10-16 years. For the 4 age groups in the 6 facilities that responded, the mean, 25th, 50th, and 75th percentile values of CTDIvol (mGy) for head CT were for infants (<1 year), 21.2, 14.4, 17.6, and 27.0, respectively; for 1-5 years, 36.5, 15.7, 34.5, and 38.1, respectively; for 5- to 10-year group, the CTDIvol was found to be 40, 15.7, 33.5, and 47.6, respectively, and for the last group of 10-16 years, 41.6, 15.7, 37.4, and 58.3, respectively. The corresponding DLP (mGy • cm) for head CT, the mean, 25th, 50th, and 75th percentile values were as follows: for infants (<1 year), 472.9, 326.9, 385.3, and 545.5, respectively; for 1-5 years, 742.9, 509.1, 689.3, and 902.9, respectively; for 5-10 years, 1,130.4, 501.7, 924.2, and 1,667.4, respectively; for 10-16 years, 1,226.4, 595.4, 870.1, and 1,255.3, respectively. The total mean CTDIvol (mGy) was 38.0, and the total mean DLP (mGy · cm) was 1,001.6. These values have been compared with other values from other similar studies; the summary for these comparisons concluded that the majority of CTDIvol 16-cm phantom and DLP 16-cm phantom values for the head were higher than DRLs reported from other studies in other countries. Therefore, for risk reduction, it is necessary to establish DRLs for pediatric CT in Sudan.