Muscle tension dysphonia as a sign of underlying glottal insufficiency

BACKGROUND: Hyperkinetic vocal function (muscle tension dysphonia) may be an indication of underlying glottal insufficiency. In the face of an organic voice disorder such as presbylaryngis or vocal fold paresis. Hyperkinetic laryngeal behaviors may be used to achieve glottal closure. Such compensatory laryngeal behaviors may mask the correct underlying diagnosis. OBJECTIVE: We sought to evaluate the association between vocal fold bowing due to presbylaryngis and abnormal muscle tension patterns (MTPs). METHODS: One hundred consecutive volunteers >40 years old were prospectively evaluated. All underwent a comprehensive head and neck examination that included transnasal fiberoptic laryngoscopy with videostroboscopy. Abnormal MTPs were compared in subjects with and without vocal fold bowing. RESULTS: The mean age of the cohort was 61 years. Eighty-four percent (42 of 50) of the male subjects and 60% (30 of 50) of female subjects had evidence of vocal fold bowing. Of the 72 patients with bowing, 94% (68 of 72) had abnormal MTPs. Compared with subjects without vocal fold bowing, persons with bowing were 17 times more likely to exhibit abnormal MTPs (P < 0.001). CONCLUSIONS: Abnormal MTPs are common in persons with underlying glottal insufficiency. Patients with vocal fold bowing are 17 times more likely to exhibit abnormal MTPs (95% confidence interval, 4.9 to 59.4). Clinicians should be aware that compensatory hyperkinetic laryngeal behaviors may mask an underlying organic condition.