[The impact on diagnostic quality of using contrast media in PET-CT studies]

To evaluate the impact of using radiologic contrast media on the quality of PET-CT studies at our center.

This is a retrospective observational study to evaluate the quality of the PET-CT studies carried out with radiologic contrast media and the presence of artifacts due to these contrast agents. Oncologic patients in whom PET was indicated according to the manufacturer's specifications for FDG ((18)F-2-fluoro-2-deoxy-D-glucose) underwent PET-CT study on a PET-CT system with a six-detector-row CT scanner.

Between February 2009 and June 2009, we performed 612 PET-CT examinations in 369 male patients and 243 female patients. Iodinated contrast media were administered intravenously in 48% and orally in 18%. Diagnostic quality was considered high in 93.5% of the studies, intermediate in 4.3%, and low in 2.2%. In the CT studies performed using intravenous contrast agents, artifacts were identified in 8% and resulted in diagnostic uncertainty in the PET study in 1.4%. We found no diagnostic problems caused by oral contrast agents in any case.

The use of radiologic contrast agents in PET-CT studies does not negatively affect diagnostic quality or workflow. Given that we can improve the ability of PET-CT to detect lesions by enhancing the diagnostic quality of the CT study, we consider it appropriate to include the administration of contrast agents in protocols for PET-CT studies.