RADIATION EXPOSURE RESULTING FROM DIGITAL VOIDING CYSTOURETHROGRAPHY IN CHILDREN - HOW MUCH IS DUE TO FLUOROSCOPY

Objective: Determination of the proportion of the dose-area product ca used by fluoroscopy at voiding cystourethrography in children, using d igital image intensifier technology. Patients and methods: Using compu ter-assisted dosimetry, we determined the dose-area product and the re spective proportions of the dose-area product caused by fluoroscopy an d radiography as well as the number of radiographs taken at a given ex amination of 40 children (8 children less than 2 years old, 15 childre n between 2 and 6 years old and 17 children between 6 and 15 years old ). Results: The computer software program correctly differentiated bet ween fluoroscopy and radiography in 80 % of cases. Incorrect results w ere primarily observed in newborns and young children. The total radia tion dose ranged in relation to patient age from 23 to 651 cGy x cm(2) . Fluoroscopy was responsible for an average 75% of the applied radiat ion dose. Conclusion: Computer-assisted dosimetry is useful in determi ning the proportion of the dose-area product caused by fluoroscopy in older children undergoing voiding cystourethrography. When image inten sifier technology is used, this accounts for more than 75% of the tota l radiation dose. The method is not suitable for use in small children .