RESUMO
BACKGROUND: The optimization of radiological examinations is important in order to reduce unnecessary patient radiation exposure. PURPOSE: To perform a comprehensive optimization process for paranasal sinus radiography at Mikkeli Central Hospital, Finland. MATERIAL AND METHODS: Patients with suspicion of acute sinusitis were imaged with a Kodak computed radiography (CR) system (n=20) and with a Philips digital radiography (DR) system (n=30) using focus-detector distances (FDDs) of 110 cm, 150 cm, or 200 cm. Patients' radiation exposure was determined in terms of entrance surface dose and dose-area product. Furthermore, an anatomical phantom was used for the estimation of point doses inside the head. Clinical image quality was evaluated by an experienced radiologist, and physical image quality was evaluated from the digital radiography phantom. RESULTS: Patient doses were significantly lower and image quality better with the DR system compared to the CR system. The differences in patient dose and physical image quality were small with varying FDD. Clinical image quality of the DR system was lowest with FDD of 200 cm. Further, imaging with FDD of 150 cm was technically easier for the technologist to perform than with FDD of 110 cm. CONCLUSION: After optimization, it was recommended that the DR system with FDD of 150 cm should always be used at Mikkeli Central Hospital. We recommend this kind of comprehensive approach in all optimization processes of radiological examinations.
