[Stroboscopic study of the respiratory mucosal ciliary beat frequency].

Abnormalities of the ciliary function have been found as an important factor in chronic respiratory diseases. For the study of the ciliary beat frequency, we developed a stroboscopic method using a stroboscopic illuminator ( Strobo Hertz) substituted to the normal light of an inverted optic microscope (Leitz). The ciliated cells obtained either by nasal scraping or tracheobronchial brushing were maintained in a culture medium (IP 199) at 37 degrees C. The ciliary beat frequency was measured at various times, at least one hour after the sampling. Nasal scraping, was performed with a curette in 17 children from 10 months to 16 years who complained of chronic respiratory diseases. Ciliated cells were obtained in 14 samples. In one of them 5 years old with a situs inversus, although the ciliated cells were numerous, the cilia appeared immotile. In the 13 others, the frequency was from 7 to 11.5 Hz with a mean of 10.8 Hz. These results were compared to those obtained by tracheobronchial brushings performed in 7 patients from 4 months to 46 years who underwent an endoscopic investigation. The ciliary frequency was 7 to 10 Hz with a mean of 8.5 Hz. The study of the ciliary beat frequency obtained by nasal scraping seems to be a reliable method for the detection of abnormal ciliary function. Nasal scraping is a non invasive method. Moreover, the stroboscopic method is a non expensive tool.