Combined strategies lower pediatric CT radiation dose

The combination of tube current modulation and bismuth shields during pediatric chest CT scanning can reduce radiation dose with a minimal impact on image quality, according to researchers from Duke University and the University of Arkansas.

Although both techniques have been shown to effectively lower CT radiation dose, the effect of their combined use on dose reduction and image quality has never been assessed, according to coauthor Dr. Donald P. Frush, chief of pediatric radiology at Duke. On paper, it appeared that the scanner might increase the dose to penetrate the shield. The investigators tested shields on a childlike phantom after the scout CT scan used to determine tube current modulation. They found the technique lowered total dose by more than 50% with only minimal image noise (AJR 2008;190:W54-W61).