Vocal function following hemilaryngectomy.

Vocal function following hemilaryngectomy was investigated in 54 cases in which a superiorly based sternohyoid muscle flap was used for glottic reconstruction. Four types of material were employed for covering the muscle flap: hypopharyngeal mucosa, lip mucosa, thyroid perichondrium, and island cervical skin flap. The vocal function varied greatly from individual to individual; however, the following tendencies were observed in many cases: 1) the glottis did not close completely; 2) supraglottic structures (false fold, arytenoid region, and epiglottis) were hyperfunctional and vibrated instead of or together with the unaffected vocal fold; 3) vibrations of the laryngeal structures were irregular; 4) maximum phonation time was short; 5) mean airflow rate was high; 6) fundamental frequency and intensity ranges of phonation were limited; 7) the voice was rough, breathy, and/or strained; and 8) cases with poor vocal function were most frequent in the skin flap group and least frequent in the lip mucosa group.