Paranasal sinus ventilation in healthy subjects and in patients with sinus disease evaluated with the 133-xenon washout technique.

Ventilation of the paranasal sinuses is of great importance in sinus pathophysiology. Therefore, methods of measuring sinus ventilation are important for the evaluation of patients with sinus disease. In the present study, a 133-xenon washout technique was used to evaluate the ventilation of the paranasal sinuses in 34 healthy subjects and in 13 subjects with sinus disease (5 patients with nasal polyposis and 8 patients with chronic sinusitis). For this purpose, a 133-xenon-air mixture was insufflated in each nostril and the washout of the radioactive gas from the paranasal sinuses was monitored with a dynamic single-photon-emission computed tomography camera. The half-time (+/-SD) was found to be 18 +/- 18 minutes for the maxillary sinus, 10 +/- 8 minutes for the frontal sinus, and 18 +/- 23 minutes for the posterior ethmoid and sphenoid sinuses in the healthy subjects. Repeated measurements in 18 of the healthy subjects indicated that the method had acceptable reproducibility according to a Bland-Altman plot. The 133-xenon washout was not influenced by insufflation pressure, nasal patency, or body position. The subjects with sinus disease exhibited half-times of 77 +/- 101 minutes for the maxillary sinus, 91 +/- 124 minutes for the frontal sinus, and 60 +/- 60 minutes for the posterior ethmoid and sphenoid sinuses. For patients with nasal polyposis, the half-time was significantly longer than that in healthy subjects, while patients with chronic sinusitis did not differ from healthy subjects in this respect.