RESUMO
BACKGROUND: Today's gold standard for diagnostic imaging of inflammatory diseases of the paranasal sinus is computed tomography (CT). PURPOSE: To evaluate diagnostic sensitivity and radiation dose of an ultra-low dose dual-source CT technique. MATERIAL AND METHODS: Paranasal sinuses of 14 cadaveric heads were independently evaluated by two readers using a modern dual-source CT with lowest reasonable dosage in high-pitch mode (100 kV, 10 mAs, collimation 0.6 mm, pitch value 3.0). Additionally the head part of an anthropomorphic Alderson-Rando phantom was equipped with thermoluminiscent detectors to measure radiation exposure to the eye lenses and thyroid gland. RESULTS: Diagnostic accuracy regarding sinusoidal fluid, nasal septum deviation, and mucosal swelling was 100%. Mastoid fluid was detected in 76% and 92%, respectively. In the phantom study, average measured eye lens dosage was 0.64 mGy; radiation exposure of the thyroid gland was 0.085 mGy. CONCLUSION: Regarding evaluation of inflammatory diseases of the paranasal sinus this study indicates sufficient accuracy of the proposed CT protocol at a very low dosage level.