Automated effective dose estimation in CT

European regulations require the dose delivered to patients in CT examinations to be monitored and checked against reference levels. Dose estimation has traditionally been performed manually. This is time consuming and therefore it is typically performed on just a few patients and the results extrapolated to the general case. In this work an automated method to estimate the dose in CT studies is presented. The presented software downloads CT studies from the corporative picture archiving and communication system and uses the information on the DICOM headers to perform the dose calculation. Automation enables dose estimations to be performed on a larger fraction of studies, enabling more significant comparisons with diagnostic reference levels (DRLs). A preliminary analysis involving 5800 studies is presented with details of dose distributions for selected CT protocols in use at a university hospital. Average doses are compared with DRLs. Effective dose estimations are also compared with estimations based on the dose length product.