Determination of dosimetric quantities in pediatric abdominal computed tomography scans.
OBJECTIVE
Aiming at contributing to the knowledge on doses in computed tomography (CT), this study has the objective of determining dosimetric quantities associated with pediatric abdominal CT scans, comparing the data with diagnostic reference levels (DRL).


METHODS
The study was developed with a Toshiba Asteion single-slice CT scanner and a GE BrightSpeed multi-slice CT unit in two hospitals. Measurements were performed with a pencil-type ionization chamber and a 16 cm-diameter polymethylmethacrylate trunk phantom.


RESULTS
No significant difference was observed in the values for weighted air kerma index (CW), but the differences were relevant in values for volumetric air kerma index (CVOL), air kerma-length product (PKL,CT) and effective dose.


CONCLUSIONS
Only the CW values were lower than the DRL, suggesting that dose optimization might not be necessary. However, PKL,CT and effective dose values stressed that there still is room for reducing pediatric radiation doses. The present study emphasizes the importance of determining all dosimetric quantities associated with CT scans.
Master, PhD student in Clinical Radiology, Department of Imaging Diagnosis - Escola Paulista de Medicina da Universidade Federal de São Paulo (EPM-Unifesp), São Paulo, SP, Brazil.
Tiago da Silva
Tda S
Jornada
PhD, Senior Researcher, Comissão Nacional de Energia Nuclear (CNEN), Teacher of the Post-graduation Course at Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN), Belo Horizonte, MG, Brazil.
Teógenes Augusto
TA
da Silva
Air kermalength product; Dosimetric quantities; Pediatric computed tomography scans; Volumetric air kerma index; Weighted dose index