ASSESSMENT OF ENTRANCE SKIN DOSE FOR PATIENTS AND STAFF EXPOSURE DURING X-RAY RADIOGRAPHY

Abstract

In this study, the entrance skin dose (ESD) for patients and staff exposure during X-ray examinations were determined at the General Hospital, Alade-Idanre and the State Specialist Hospital, Akure, both hospitals in Ondo State, Nigeria, were determined using Thermoluminescence dosimeters (TLD). Exposure results were taken from 18 patients and 6 staff at the General Hospital, Alade-Idanre and 96 patients from the State Specialist Hospitals, Akure. The parts of the body investigated were ankle, chest, leg, knee, hand, shoulder and skull. The radiographic techniques investigated were anterior-posterior (AP), posterior-anterior (PA) and lateral (LAT) projections. The patient body characteristics measured were weight and height, from which the body mass index (BMI) was calculated and the radiographic X-ray machine exposure parameters recorded are tube current and voltage, as well as focus to skin and focus to image receptor distances. The mean and standard deviation for the patient ESD at the General Hospital, Alade-Idanre are 0.31 for hand LAT, 0.29 for shoulder AP, 0.33 ± 0.07 for chest AP, 0.41 ± 0.11 for chest PA, 0.31 ± 0.01 for chest LAT, 0.36 ± 0.05 for skull AP, 0.41 for leg AP and 0.31 mSv for leg LAT; and for the State Specialist Hospital, Akure, are 0.36 ± 0.04 for ankle AP, 0.34 ± 0.04 for ankle LAT, 0.31 for hand AP, 0.40 ± 0.01 for hand LAT, 0.31 for chest AP, 0.38 ± 0.06 for chest PA, 0.36 ± 0.04 for chest LAT, 0.29 ± 0.02 for tibia/fibula AP, 0.35 ± 0.09 for tibia/fibula LAT, 0.39 ± 0.06 for knee AP, 0.37 ± 0.10 for knee LAT, 0.39 ± 0.02 for skull AP, 0.40 ± 0.05 for skull PA and 0.43 ± 0.04 mSv for skull LAT. These results are low compared to those obtained from other studies and International diagnostic reference levels. The staff exposure at the General Hospital, Alade-Idanre are 0.37 mSv for SE1, 0.38 for SE2, 0.40 mSv for SE3, 0.57 mSv for SE4, 0.49 mSv for SE5 and 0.36 mSv for SE6. Statistical analysis of the results was carried out using the IBM SPSS software to determine if the patient’s body characteristics and X-ray radiography machine exposure parameter have an impact on the variation of the patient’s ESD. With the results obtained, the patient’s ESD to a large extent shows no particular trend.