Quantitative evaluation of phonetograms in the case of functional dysphonia.

According to the laryngeal clinical findings, figures making up a scale were assigned to vocally trained and vocally untrained persons suffering from different types of functional dysphonia. The different types of dysphonia--from the manifested hypofunctional to the extreme hyperfunctional dysphonia--were classified by means of this scale. Besides, the subjects' phonetograms were measured and approximated by three ellipses, what rendered possible the definition of phonetogram parameters. The combining of selected phonetogram parameters to linear combinations served the purpose of a phonetographic evaluation. The linear combinations were to bring phonetographic and clinical evaluations into correspondence as accurately as possible. It was necessary to use different kinds of linear combinations for male and female singers and nonsingers. As a result of the reclassification of 71 and the new classification of 89 patients, it was possible to graduate the types of functional dysphonia by means of computer-aided phonetogram evaluation with a clinically acceptable error rate. This method proved to be an important supplement to the conventional diagnostics of functional dysphonia.