PATIENT X-RAY ENTRANCE SURFACE DOSE AT A TERTIARY HOSPITAL IN SOKOTO, NORTH-WEST NIGERIA

Background: The entrance surface dose (ESD) has been used to determine the diagnostic reference levels (DRL) by regulatory bodies to help medical radiation workers to checkmate excessive dose to patients. Objective: To peer review practice in our centre using recommended diagnostic reference levels (DRLs) as standard. Methods: A prospective cross-sectional study of fifty x-ray patients who had thermoluminescent dosimeters (TLD-100) taped on their skin to quantify entrance surface dose (ESD) during x-ray investigation. The patients appeared in Radiology Department of Usmanu Danfodiyo University Teaching Hospital (UDUTH), Sokoto between 1st August and 30th September 2018. Their weights and heights were measured directly. Thereafter, they were divided into 5 groups of ten each for five specific anatomical areas: PA chest, AP of pelvis, abdomen, lumbosacral spine, and lateral lumbosacral spine. Irradiated TLDs were read, and the mean ESD was calculated. Results: Entrance surface dose (ESD) was 0.26 mGy (chest), 0.46 mGy (AP lumbosacral), 0.71 mGy (pelvis), 1.3 mGy (abdomen), and 1.6 mGy (lateral lumbosacral). The ESD values were found to be lower than similar studies carried out in Nigeria, as well as diagnostic reference levels in UK. Conclusion: Optimization of patient protection in UDUTH was comparable to recommended practices locally and internationally.