RADIATION EXPOSURE IMPLICATIONS OF PATIENTS UNDERGOING DIAGNOSTIC X-RAY EXAMINATIONS INSECONDARY PUBLIC HOSPITALS IN IBADAN, NIGERIA.

Abstract

X-ray diagnostic procedure is the most widely used procedure for diagnosis and treatment of human body. Due to direct exposure and in some cases multiple exposures of patients to X-rays during radiographic examinations, there is need for periodic checks of patient exposure dose which serves as the main monitoring tools against over-exposure. Therefore, the objectives of this study are to assess and estimate the entrance skin dose (ESD) and organ dose (ORD) received by patients undergoing diagnostic X-ray examinations in public hospitals in Ibadan using Thermo luminescent Dosimeters (TLD-100). 200 referred patients in three public hospitals were used for the survey and each patient was allocated with two TLDs to measure ESD and organ dose (ORD) during each examination. The patient clinical information or data and exposure parameters were recorded which include age, sex, weight, height, body mass index (BMI), type of examination, exposure view/projection, tube peak potential and current-time product. The results obtained for the mean ESD value and mean organ dose (ORD) value for exposed organs such as ankle (LAT), chest (PA), elbow (LAT), femur (AP), hip (AP), knee (AP), lumbar spine (AP) and lumbosacral spine (AP) were 1.99 and 1.17, 1.66 and 0.91, 1.71 and 1.00, 1.80 and 1.12, 2.19 and 1.38, 1.85 and 1.23, 8.49 and 7.20 and; 5.01 and 3.38 mGy respectively. Also, for palm or hand (AP), pelvis (AP), shoulder (AP), skull (AP), thoraxic spine (AP), tibia-fibular (LAT), upper-arm (LAT) and wrist (AP) were 1.74 and 0.89, 2.21 and 1.49, 1.76 and 1.12, 1.68 and 1.10, 7.57and 6.06, 1.70 and 1.01, 2.15 and 1.48 and; 1.98 and 1.33 mGy respectively. The ESD results obtained when compared with other published works and international DRLs were higher except for pelvis (AP), skull (AP), lumbar spine (AP), lumbosacral spine (AP) that were below and within recommended range. The study established that there were variations of doses from hospital to hospital which can be due to age and characteristics of the X-ray equipment, exposure parameters (kVp and mAs), radiographic procedures or techniques used and the body size or body mass index of patients. Therefore, there is need for strict adherence to radiation protection guidelines and the implementation of systematic and regular quality assurance/quality control (QA/QC) programme for the X-ray equipment to ensure dose optimization or reduction for patients in the public hospitals.