Effects of head and neck radiation therapy on vocal function

Objective: Radiotherapy (RT) is used to treat a variety of head and neck malignancies. The larynx may receive high radiation doses even in the absence of disease. The effects of RT on the nondiseased larynx are unknown. This study will evaluate subjective and objective parameters of vocal function in patients treated with RT for nonlaryngeal malignancies. Design: Cross-sectional observational study. Methods: Videostroboscopic, aerodynamic, and acoustic analyses were performed. Results were compared to age- and gender-matched controls. Self-assessment of voice quality was measured using the Voice Handicap Index. Results: A majority of patients demonstrated increased supraglottal activity (i.e., ventricular fold constriction) during stroboscopic evaluation. Significant differences compared to normative data were found in many aerodynamic and acoustic parameters. A substantial proportion (27%) of patients reported significant voice handicap. Younger patients reported greater handicap, and voice quality was worse with time. Conclusions: Significant objective and subjective changes in vocal function occur in patients radiated for nonlaryngeal head and neck malignancies. Young patients may have the worst impact, and vocal dysfunction may increase with time. A prospective study of this patient population should include a baseline voice quality assessment.