Comparative study of vocal function after near-total laryngectomy.

Abstract

To assess vocal function after near-total laryngectomy (NTL) and to compare that with after vertical hemilaryngectomy (VHL), both of which use the laryngeal mucosa as the vibratory tissue. We retrospectively evaluated 29 patients, 11 of whom underwent NTL and 18 of whom underwent VHL. However, 2 patients failed to speak and 1 patient's voice sample was lost following NTL, so we analyzed the voices of 8 patients who underwent NTL and 18 patients who underwent VHL. Vocal function was examined by acoustic and aerodynamic analysis. Acoustic analysis involved the evaluation of pitch, intensity, pitch perturbation quotient, amplitude perturbation quotient, and normalized noise energy. In aerodynamic analysis, we studied the mean airflow rate, vocal efficiency index (alternating current/direct current [AC/DC]), and maximum phonation time. Vocal function except pitch after either NTL or VHL had much variability, but the results following each procedure did not differ significantly. There are no significant differences between vocal function following NTL and VHL. Fiberscopic examination of the mucosa of the arytenoid was observed to vibrate in patients who underwent NTL, so that the phonatory mechanism after NTL resembled that after VHL.