Frequency spectra of normal expiratory nasal sound.

BACKGROUND

The computerized analysis of the nasal sound reflects the nasal airflow. We have developed a new software program that analyzes the nasal sound to use in the research area and clinical applications. We aimed to analyze automatically the spectral parameters of nasal sound in healthy people by our new versatile PC-based nasal sound analyzer software.

METHODS

In this study, we analyzed and recorded the expiratory nasal sound in 30 healthy people. This analysis includes the time-expanded waveform, the spectral analysis with time-averaged fast Fourier transform, the automatic detection, and the waveform analysis of nasal sound.

RESULTS

We calculated the mean frequency of low-intensity sound (LIS) and high-intensity sound (HIS). The mean frequency of LIS was found as 1254 +/- 10.23 Hz at the right nose and 1375 +/- 18.45 Hz at the left nose. The mean frequency of HIS was found as 2453 +/- 22.23 Hz at the right nose and as 2234 +/- 21.12 Hz at the left nose. These results showed that the values between LIS and HIS are statistically significant (p < 0.005) and different from each other. We found that the nasal sound of the similar nasal airflow was the same type and amplitude in the analysis of the nasal sound recordings.

CONCLUSION

The frequency of the nasal sound is an indicator of the intensity of the nasal airflow. The method that provides the analysis of the nasal sound may lead to a new diagnostic method. The method, which is noninvasive, rapid, of low cost, and even applicable for small children, requires little cooperation of the subjects. In addition, it will be possible to record and save the analysis of the nasal airflow as digital data.