Reduction of patient exposure in pediatric radiology

Rationale and Objectives. The authors determined whether presently used exposure levels in pediatric imaging be reduced without loss of information or a decrease in diagnostic accuracy. Materials and Methods. Multiple (stacked) image detectors filters were used to obtain identical computed radiographic images at different exposure levels of neonates with either no active lung disease or hyaline membrane disease. Physical characteristics of the images were measured. A contrast-detail study and a receiver operating characteristic study were conducted to measure observer performance. Results. Physical measurements and results of the contrast-detail study revealed that the dose-reduction images were essentially limited by x-ray quantum noise. Results of the receiver operating characteristic study indicated that diagnostic accuracy did not decrease significantly up to about 75% exposure reduction levels, although image quality rating data decreased with each exposure reduction. Conclusion. Decreasing exposure levels to about 75% of current levels may be acceptable in some clinical situations where dose is a concern, such as in pediatric imaging.