Is endonasal insufflation of xenon133 a fiable functional assessment of nasal cavities?

The ventilation of nasal cavities has been examined according to the method of Bisschop et al. (1983). The test was performed on 32 healthy volunteers, free of symptoms with normal standard X-rays of their sinuses. Half-times of the wash-out curves were calculated and adopted as a measure of ventilation. For sitting persons these values were lower than other authors reported, the values in sitting or lying persons were comparable. We did not find a significant difference between values of sitting or lying We did not find a significant difference between values of sitting or lying persons. There was no significant difference neither in the half-times obtained in persons with normal clinical background and persons with septal deviations. The experiment was not optimally reproducable.