VENTRICULAR FOLD DYSPHONIA - APPLICATION OF BIOFEEDBACK TECHNOLOGY TOA RARE VOICE DISORDER

A rare case of adult ventricular fold dysphonia was treated using elec tromyographic (EMG) biofeedback. Ventricular fold dysphonia is a voice disorder in which the ventricular, or false vocal folds are used to p roduce speech instead of the true vocal cords. Baseline and treatment EMG recordings were taken during nonvocalizing, counting, and conversa tional speech. Laryngeal aerodynamic and perceptual measures were also used to detect treatment effects. The treatment program was evaluated using a multiple baseline design with changing criterion. Results ind icated that EMG biofeedback was effective in reducing EMG levels durin g each of the nonvocalizing and speaking phases. Improvements were obs erved in laryngeal aerodynamic functioning, and voice quality was foun d to be markedly improved when independently evaluated by voice expert s unaware of treatment conditions. Results were maintained at 6-month follow-up, and an endoscopic examination indicated no recurring ventri cular phonation.