Patient dosimetry during chest, abdomen, skull and neck radiography in SW Nigeria

The technique factors and X-ray output from the X-ray units of three Nigerian hospitals were obtained and used to calculate doses delivered to patients during chest, abdomen, skull and neck examinations. DoseCal software was used to calculate the entrance skin dose (ESD) and effective dose (E) based on the values of technique factors employed. The result obtained for inter-hospital comparison showed wide variation of mean hospital ESD, from a factor of 1.3 for chest posteroanterior (PA) in hospital 2 (H2) to a factor of 63 for the same chest X-ray projection in hospital 1 (H1). A comparison of ESD obtained in this work with established reference doses in the United Kingdom (UK 2005 review), International Atomic Energy Agency (IAEA), Community of European Commission (CEC), Ghana and Sudan shows that the values of ESD obtained in H1 for five examinations; namely: chest (PA) and lateral (LAT), abdomen anteroposterior (AP) and skull (PA and LAT) are higher. In H2, the dose value for chest PA is about 50% higher than that of UK but comparable with CEC and less than IAEA and Ghanaian values. The dose values obtained in H3 chest PA are higher than UK, IAEA and CEC values but comparable with that of Ghana. For abdomen AP, the dose is a factor of 1.2 less than IAEA and CEC values but greater than the UK, Ghanaian and Sudanese values by a factor of 2.1, 1.2 and 4.5, respectively. Reference data for abdomen LAT and neck AP were not available for comparison. Higher effective doses are being delivered to patients in chest PA (H1 and H3) and abdomen AP (H1) when compared with the range of values reported in the literature. This trend is an indication that patients examined are at higher health risks.