Ventilation and Clearance of the Sinuses and Middle Ears Using Xenon-133

Abstract

Ventilation and clearance of xenon-133 from the pneumatic spaces of the sinuses and middle ears offers the clinician a non-invasive method for direct assessment of regional ventilatory function of sinus and middle ear cavities. Five mCi of Xe-133 are insufflated using a bilateral negative-positive displacement technique. The subsequent disappearance rate of Xe-133 is measured using a scintillation camera interfaced to a computer. Reliability has been demonstrated by repeated measurements in 40 subjects and normal half-time clearances have been established.