Vocal function following vertical hemilaryngectomy: a preliminary investigation.

Seven consecutive male patients who received a vertical hemilaryngectomy were examined for vocal function employing video-stroboscopic, aerodynamic and acoustic measurement techniques. The results of this preliminary investigation suggest that with the group of patients studied, vocal quality was rated as "rough", "breathy" and "constricted". While large variability was noted between individuals, the general tendencies for the group included: (a) incomplete glottic closure; (b) supraglottic structures (ventricular folds, arytenoids) fulfilled or aided vibratory action of the remaining fold; (c) high average transglottal airflow; (d) reduced maximum phonation time; (e) high and more variable vocal frequency positioned near the top of the frequency range; (f) a lower, more variable, and restricted vocal intensity range, and (g) a reduced vocal fold diadochokinetic (vocal fold opening and closing action) rate. We are currently attempting to determine factors related to individual patient strategies for using either glottic or supraglottic valving during phonation.