Normal values of mucociliary transport time in young subjects.

The authors studied the behaviour of nasal mucociliary transport (MCT) in 54 (33 female/21 male) normal children aged between 3 and 12 years, in orthostatic and clinostatic positions. The nasal MCT time was recorded with the stained tracer method; vegetal coal powder was used since it fulfills the required characteristics: it is neither toxic, nor soluble and can be easily detected. The examinations were carried out at the same time of day on two consecutive days under the same conditions of temperature and relative humidity. The statistical analysis of the results indicated an average nasal MCT time of 9.96 +/- 2.61 min in the orthostatic (upright) position and of 9.98 +/- 2.31 min in the clinostatic (lying) position: these values should be considered normal. No statistically significant difference was noted attributable to sex or posture.