Radiation exposure of children in pediatric radiology. Pt. 7. Conversion factors for reconstruction of organ dose during thoracoabdominal babygrams

Purpose: Calculation of conversion coefficients for the reconstruction of organ doses from entrance doses for thoracoabdominal babygrams of premature neonates with a gestational age of 23 and 27 weeks and of mature neonates. Materials und Methods: Using the commercially available personal computer program PCXMC developed by the Finnish Centre for Radiation and Nuclear Safety (Saeteilyturvakeskus STUK), conversion coefficients for conventional thoracoabdominal babygrams were calculated with Monte Carlo simulations in mathematical hermaphrodite phantom models describing patients of different ages. Results: Conversion coefficients for the reconstruction of organ doses in approximately 40 organs and tissues of the human body from measured entrance doses during thoracoabdominal babygrams were calculated for the standard sagittal beam projections and the standard focus film distance of 100 cm. Conclusion: The conversion coefficients presented in this paper may be used for organ dose assessments from entrance doses measured during thoracoabdominal babygrams especially in patients in special care baby units. (orig.)