Acoustic analysis of pathological cries, stridors and coughing sounds in infancy.

In the examination of respiratory pathological sound phenomena in infancy (pathological crying, stridor and coughing sounds), besides the subjective-auditive observations and traditional examination methods (X-ray, endoscopy), acoustic analysis, as a new branch of bioacoustics, may be of much help. The various pathological infant vocalizations originating from the air passageways are merely symptoms, but they may furnish important diagnostic clues. Approximately 200 recordings of pathological sound signals derived from 180 infants suffering from 40 different diseases or anomalies were analyzed by means of sound spectrography, the fundamental frequency meter, and rarely, the minimal-time-interval spectra technique. The acoustical evaluation of the sound phenomena are not only of scientific and documentative value; they are also of great help in diagnostics and prophylaxis, in the suitable choice of diagnostic tools and in education and further training, i.e. in the everyday work of the pediatric otolaryngologist.