Optimización de protocolo en tomografía computerizada pediátrica con control automático de exposición

Abstract

ObjectiveThe aim of this work is to describe the optimization of a posterior fossa protocol in pediatric computed tomography (CT) by using an Automatic Exposure Control (AEC) system, named Flex-mA (SHIMADZU Corp., Kyoto, Japan). Materials and methodsThe calculation of the CT dose index over the entire volume, Cvol, and the kerma-length product in air, PKT,CT, was based on the Cvol reported by the CT unit, with slice thickness and tube current being taken from metadata of patient's DICOM files. The estimated mean dose levels were compared between each other and with respect to Dose Reference Levels (DRLs) by multiple comparison of means. ResultsSignificant dose reductions were obtained for all age ranges from 1year to 19years old, with minimum reductions up to 31% for the Cvol and 25% for the PKT,CT, compared with DRLs from developed countries in a range from 10 to 14years old. ConclusionsThe use of the AEC function, Flex-mA, allows both the average value and the dispersion of Cvol and PKT,CT for pediatric patients to be evaluated, preserving an acceptable level of the diagnostic image quality according to international criteria of quality of head imaging protocols in general.