DEVELOPMENT OF A JAPANESE INFANT HEAD–CHEST PHANTOM AND INVESTIGATION OF THE CURRENT STATUS OF INFANT HEAD CT EXAMINATIONS IN JAPAN.

The aim of this study was to develop a head–chest phantom that could mimic the physique of a Japanese 0.5-year-old child and to investigate the current status of exposure dose in infant head computed tomography examinations in Japan. The phantom was produced by machine processing, and radiophotoluminescence glass dosemeters were installed in the phantom for dose measurement. Organ doses were measured for seven different head scan protocols routinely used in three hospitals. In this study, the average dose of the brain and lens within the scan region was equivalent to that measured using infant phantoms in previous studies. In contrast, the doses of both salivary glands and thyroid glands adjacent to the scan region were 1.4–1.8 times higher than those in previous studies. Expansion of the scan area accompanied by a transition of the scan mode from non-helical to helical may have resulted in the differences in organ doses. [ABSTRACT FROM AUTHOR]