Investigation of radiation dose to pediatric patients from computed tomography examinations at Muhimbili national hospital and Mnazi mmoja hospital in Tanzania

The purposes of this study were to determine the magnitude of radiation dose delivered to pediatric patients (0 – 15 years) undergoing CT examinations at MNH and MMH and to assess the influence of CT scanning protocols on the delivered dose. A total of 100 pediatric patients were investigated. The dose indicators (CTDIvol, CTDIw, DLP, ED and Organ dose) were estimated by using CT Expo a computer based program. The mean dose across all age categories were (34.7 – 77.23 mGy) (CTDIvol), (16.7 – 36.35 mGy) (CTDIw), (498.89 – 685.67 mGy cm) (DLP) and (1.62 – 2.49 mSv) (ED) for head CT at MMH. The mean doses for head, chest and abdomen CT at MNH ranged as follows: (25.04 – 33.66 mGy), (1.53 – 4.4 mGy) and (2.5 – 6.36 mGy) (CTDIvol), (653.26 – 946 mGy cm), (39.67 – 219.7 mGy cm) and (91 – 327. 78 mGy cm) (DLP), (6.03 – 9.18 mSv), (1.35 – 1.77 mSv) and (1.55 – 5.17 mSv) (ED), respectively. The mean organ dose (in mSv) per scan series of some radiosensitive organs such as bone marrow, skin, lenses and thyroid were 9, 8.1, 35 and 31.8, respectively. The mean CTDIvol obtained at MNH was comparable to or lower than that reported from South Korea, Portugal, RCH of Australia, Uganda and Belgium while that obtained at MMH was higher than South Korea, Portugal and Uganda. The mean DLP of MMH was similar to or less than that reported for South Korea, Portugal and Belgium while of MNH was high for head CT. Furthermore, kV, mAs and scan length were found to have influence on CTDIvol and DLP. Therefore, there is a potential for optimization and standardization of scanning protocols in both hospitals.