Abstract
In general, the primary therapy for mutational voice disorder has been voice therapy. However, we sometimes see cases in which voice therapy does not decrease the high pitch of mutational voice disorder. We performed an Isshiki type III thyroplasty on a patient with mutational voice disorder who had been treated by voice therapy for two years without remarkable improvement of his voice. His voice pitch became much lower after the Isshiki type III thyroplasty surgical procedure. The patient's fundamental frequency (F0) decreased from 276 Hz before surgery to 126 Hz after surgery. Isshiki type III thyroplasty was found to be useful as surgical treatment for higher pitch and resulted in a voice that was satisfactory to the patient with mutational voice disorder.
