Entrance Surface Dose from Pediatric Diagnostic X-ray Examinations in a Developing World Setting: Are We ‘ALARA Principle’ Compliant?

Background: Radiation protection in paediatric radiology requires special attention than in adult because children are more sensitive to radiation and at higher risk. This risk is explained by the longer life expectancy in children which allows for harmful effects of radiation to manifest and their developing organs and tissues being more sensitive to radiation. Hence, the need for determination of appropriate radiation dose for paediatric patients.
Aims: To estimate entrance skin dose (ESD) received by paediatric patients during diagnostic x-ray examinations.
Materials and Methods: A total of 253 paediatric patients undergoing various x-ray examinations between June 2011 and December, 2012 in a teaching hospital in the South West Nigeria were considered in this study. This hospital has no dedicated x-ray unit for paediatric radiology. The ESD received during x-ray examination was calculated using mathematical formula that incorporated the use of x-ray beam output and exposure parameters selected for the examination. Correlation coefficient (r) analysis was used to test the relationship between ESD, patient size (age and weight) and exposure parameters (kVp, mAs).
Results: The ESD and ED received by paediatric patients from all the x-ray examinations considered in this study ranged from 10.29 ± 3.80 - 880.04 ± 89.44 µGy and 1.44 ± 0.53 - 66.74 ± 30.84 µSv respectively. The correlation coefficient analysis at 0.01 level of significant showed that there is a correlation between patient dose and exposure factors but there is no correlation between ESD, age and weight of patients.
Conclusion: The ESD received by paediatric patients is higher than the internationally recommended reference dose. This is attributed to lack of dedicated x-ray unit and personnel for paediatric radiology.