Analysis of the phonation onset process of the vocal folds for diagnosis of functional dysphonias

T. Braunschweig, J. Flaschka, P. Schelhorn-Neise1, M. Döllinger

An objective method for the diagnosis of functional dysphonias will be presented. The mathematically motivated approach was evaluated on 75 female subjects with normal voice or functional dysphonia. Using digital high-speed recordings, the phonation onset process was recorded in real time for 8 to 10 different sound pressure levels for each subject. From these recordings two parameters were mathematically estimated, reflecting the phonation onset dynamics. The growth of the vocal fold amplitudes during the phonation onset process was described by a parameter a for which its lower threshold value ath was extrapolated. This threshold reflects the myoelastic tonus within the vocal folds. The second parameter was the maximum sound pressure level Lmax of comfortable speech reflecting the necessary subglottal pressure needed for phonation.
Due to the significant differences of these parameters between the patients with functional voice disorders and normal voices, the presented method is a reliable and objective tool for voice diagnostics.

T. Braunschweig1, J. Flaschka1, P. Schelhorn-Neise1, M. Döllinger2
1 University Hospital Jena, Department of Phoniatrics and Pediatric Audiology, Stoystr. 3, 07743 Jena, Germany
Phone: ++49-3641-936434, fax: ++49-3641-935445
email: Thomas.Braunschweig@med.uni-jena.de
2University Hospital Erlangen, Medical School, Department of Phoniatrics and Pediatric Audiology, Bohlenplatz 21, 91054 Erlangen, Germany.