Estimation of patient organ doses from CT examinations in Tanzania

Although the use of CT in medical diagnosis delivers radiation doses to patients that are higher than those from other radiological procedures, lack of optimized protocols could be an additional source of increased dose in developing countries. The aims of this study are, first, to determine the magnitude of radiation doses received by selected radiosensitive organs of patients undergoing CT examina-tions and compare them with other studies, and second, to assess how CT scanning protocols in practice affect patient organ doses. In order to achieve these objec-tives, patient organ doses from five common CT examinations were obtained from eight hospitals in Tanzania. The patient organ doses were estimated using mea-surements of CT dose indexes (CTDI), exposure-related parameters, and the ImPACT spreadsheet based on NRPB conversion factors. A large variation of mean organ doses among hospitals was observed for similar CT examinations. These variations largely originated from different CT scanning protocols used in differ-ent hospitals and scanner type. The mean organ doses in this study for the eye len