Phonatory airflow analysis in patients with laryngeal disease

Phonatory airflow was recorded in 150 patients with various laryngeal diseases and in 60 persons with normal voices. All subjects produced several sustained vowels at different loudness levels. Disturbances of voice due to laryngeal disease may be manifested as variations of mean flow (DC), alternating flow (AC), or as a variation in the amplitude of the frequency components of the airflow signal (frequency spectra). The quantification of airflow characteristics is important if the clinician is to have a better understanding of laryngeal disease. Furthermore, preoperative and postoperative analysis can serve to document therapeutic effectiveness.