Vocal Fold Vibration After Microsurgery of the Larynx

Abstract

The author investigated the influence of microsurgical intervention of the canine larynx to vocal fold vibration. (1) Normal case: bilateral lower lips and free edges vibrated symmetrically. Lower lips coincided with free edges and met together at the midline. Then, lower lips rapidly moved apart laterally. They stayed at the most lateral points until both free edges started to move apart laterally. After that, they began to move medially to meet together again when free edges were moving away laterally. (2) Cases after microsurgical intervention: a part of the mucosal layer of the upper surface or the lower surface of the vocal fold was removed. Several weeks after the procedures, vibration was observed. In either case, vibration of the free edge of the operated vocal fold became smaller in amplitude and often became earlier in phase than that of the other side. Usually lower lip of the operated vocal fold moved away slower. In addition, when the extent of epithelial removal was large vibration of lower lip was not elicited.