Xenon-enhanced computed tomography quantifies normal maxillary sinus ventilation

OBJECTIVE: The purpose of this study was to determine the applicability, sa fety, and normal parameters of a xenon-enhanced CT technique to quantify ma xillary sinus ventilation. PATIENTS AND METHODS: Nine healthy subjects inhaled a xenon-oxygen-air mixt ure through their noses while repeated CT scans were performed through the same section of their sinuses. Images were obtained every 1 to 3 minutes an d analyzed to measure the density of the gas in the maxillary sinus as a fu nction of time. RESULTS: individual nasal cavity time constants ranged from 0.5 to 18 minut es. Studies performed after decongestion showed poorer sinus ventilation. CONCLUSIONS: The xenon-CT washin/washout technique is safe, effective, and gives representative data.