Vocal evaluation of thyroplasty type I in the treatment of nonparalytic glottic incompetence.

This study investigated the prethyroplasty and postthyroplasty voices of patients with glottic incompetence of mobile vocal folds related to vocal fold bowing and scarring. Seventeen patients underwent vocal function evaluation preoperatively and 1 month postoperatively with videostrobolaryngoscopic examination, acoustic and aerodynamic analysis, and perceptual judgment of voice characteristics. The postoperative voice outcome in this group of patients was compared to that of a group of patients with unilateral vocal fold paralysis. Patients with vocal fold bowing showed significant improvement in glottic gap size and hoarseness after the surgery. There was minimal improvement on other test measures. Patients with vocal fold scarring exhibited worse preoperative and postoperative vocal functions, with little voice improvement after surgery. The outcome of thyroplasty type I in cases of vocal fold bowing or scarring is not as good as that in unilateral vocal fold paralysis.