Sixty female adults with vocal cord nodules were examined and treated with voice therapy using phonolaryngograph. The results were as follows.
1. It was considered that vocal cord nodules were caused by vocal abuse following factors might also be the considered; the neck and shoulder stiffness, hard glottal attack, singing or speaking with innappropriate voice range.
2. For visual feedback training, a phonolaryngograph was used for simultaneously indicating the time courses of air flow rate, intensity and pitch of voice on the screen. This training method was simple and proved effective for voice therapy,
3. Laryngoscopic observations revealed that vocal cord nodules either disappeared or redused in size within 6 months of voice therapy in 70% of the cases.
4. Treatment of vocal cord inflammation appeared to give an additional effect the result of voice.
5. In according with improvement of vocal nodules, hoarseness improved.
6. On soundspectrographic analysis, an increase in higher harmonics and a decrease in noise components were generally observed.
7. In one of the present cases, a computer analysis revealed a decrease in the values of PPQ, APQ, and noise level. In the course of training of soft voice production, an increase in noise level with a decrease in richness of harmonics were observed.