Assessment of low doses during diagnostic procedures using beo detectors and OSL technique

Abstract

Advances in imaging techniques with the use of radiation increased the quality and power of medical diagnostic. At the same time, concerns about the doses to patients arose in the radiation protection community. According to UNSCEAR (United Nations Scientific Committee on the Effects of Atomic Radiation), the second main contribution to the population annual dose is from exposure in medical procedures. Although the doses are relatively low in diagnostic, the number of exams for the same patient is growing, bringing especial attention to doses to children or to radiosensitive regions in the body. International organizations recommend the establishment of reference levels in diagnostic procedures and the tracking of the patient exposures. Considering this, we studied the use of optically stimulated luminescence (OSL) and thermoluminescent (TL) techniques together for assessment of skin doses in simulated (pediatric phantom) and real patients during diagnostic procedures. BeO and LiF detectors were used in mammography and radiographic procedures, and in CT examinations. The results of TL and OSL were compared to each other and to international reference levels, when it was possible. Both detectors were able to evaluate doses in the range of 15, µGy to 100, mGy. BeO detectors presented compatible results with LiF detectors for doses in the range of few mGy and low uncertainties in the range of µGy, for both, adults and pediatric patients. We can conclude that the advantages of OSL technique combined to intrinsic characteristics of BeO (tissue equivalence and flat energy response for photons up to 100, keV) can be explored for assessment of patient doses in diagnostic procedures.