Nationwide survey of radiation exposure during pediatric computed tomography examinations and proposal of age-based diagnostic reference levels for Japan.
BACKGROUND
Diagnostic reference levels (DRLs) have not been established in Japan.


OBJECTIVE
To propose DRLs for CT of the head, chest and abdomen for three pediatric age groups.


METHODS
We sent a nationwide questionnaire by post to 339 facilities. Questions focused on pediatric CT technology, exposure parameters, CT protocols, and radiation doses for age groups <1 year, 1-5 years, and 6-10 years.


RESULTS
For the three age groups in the 196 facilities that responded, the 75th percentile values of volume CT dose index based on a 16-cm phantom (CTDIvol 16 [mGy]) for head, chest and abdominal CT were for infants 39.1, 11.1 and 12.0, respectively; for 1-to 5-year-olds 46.9, 14.3 and 16.7, respectively; and for 6-to 10-year-olds 67.7, 15.0 and 17.0, respectively. The corresponding dose–length products (DLP 16 [mGy・cm]) for head, chest and abdominal CT were for infants 526.1, 209.1 and 261.5, respectively; for 1-to 5-year-olds 665.5, 296.0 and 430.8, respectively; and for 6-to 10-year-olds 847.9, 413.0 and 532.2, respectively.


CONCLUSIONS
The majority of CTDIvol 16 and DLP 16 values for the head were higher than DRLs reported from other countries. For risk reduction, it is necessary to establish DRLs for pediatric CT in Japan.
Yasutaka
Y
Takei
Osamu
O
Miyazaki
Kosuke
K
Matsubara
Yoshiya
Y
Shimada
Yoshihisa
Y
Muramatsu
Keiichi
K
Akahane
Keisuke
K
Fujii
Shoichi
S
Suzuki
Kichiro
K
Koshida
D017677:Age Distribution; D002648:Child; D002675:Child, Preschool; D005260:Female; D019538:Health Care Surveys; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007564:Japan / Q000453:epidemiology; D008297:Male; D008452:Maximum Allowable Concentration; D017410:Practice Guidelines as Topic; D000069079:Radiation Exposure / Q000592:standards* / Q000706:statistics & numerical data*; D012016:Reference Values; D017678:Sex Distribution; D014057:Tomography, X-Ray Computed / Q000592:standards* / Q000706:statistics & numerical data*