Contemporary Review: Impact of primary neopharyngoplasty on acoustic characteristics of alaryngeal tracheoesophageal voice

Abstract

The physiology of the vibratory mechanism in alaryngeal tracheoesophageal speech depends on several factors. The structure and resulting function of the neoglottis (or neopharynx) varies from patient to patient depending on the individual details of the surgical procedure performed, as well as the patient's anatomy. In general, the vibratory segment is a blending of the pharyngeal constrictor muscles, cricopharyngeus, and upper circular fibers of the esophagus. Limited ability to visualize dynamically these three-dimensional structures during rapid events of voice and speech production impedes complete understanding of the vibratory function of the neopharynx. Acoustic studies have elucidated some general characteristics of the pharyngoesophagus and neoglottic vibratory mechanism in the laryngectomized population. A critical degree of tonicity is necessary for apposition of mucosal surfaces in the production of tracheoesophageal voice. Deficiencies in the vibratory segment can usually be managed with various surgical procedures (neopharyngoplasty), resulting in reduced intraesophageal pressure and corresponding increase in fluent, intelligible, effortless speech. The acoustic measures, when correlated with neopharyngoplasty variables, produce many significant associations. Some of them are paramount and deserve further attention.

Total Laryngectomy: A Review of Surgical Techniques

“…It is assumed that the T-shaped closure causes less tension than the vertical closure in some defect shapes. The horizontal closure appears to be the ideal closure line because it avoids trifurcation and produces a relaxed neopharynx with improved swallowing function [64,70,71]. However, horizontal closure may not be suitable for vertically extended pharyngeal defects.…”

“…Another modified method for preventing cricopharyngeal spasm is to avoid complete circumferential repair of the pharyngeal musculature (Figure 4C-4F) [71]. Non-closure, half-muscle closure, horizontal closure, and crossover zigzag neopharyngoplasty were superior to the traditional three-layer closure.…”

The relationship between biomechanics of pharyngoesophageal segment and tracheoesophageal phonation

“…This vibrating part, referred to as the pharyngoesophageal (PE) segment, is located in the lower third of the neck, corresponding to cervical vertebrae from C5 to C7 9 . Given that voice characteristics depend on biomechanics of the vibration source 10 , the voice output of TE phonation is influenced by structure and function of the PE segment as a result of the surgical techniques and the patient’s specific anatomy 11 . Research has attempted to investigate the relationship between various characteristics of the PE segment and the resulting TE phonation 12 .…”

Voice quality and surgical detail in post-laryngectomy tracheoesophageal speakers

“…In the literature, various variables were found to affect functional outcomes. Among these, besides the extent of the resection, are the surgical method of pharynx closure and reconstruction (muscle closing techniques, donor site tissue properties), the conservation of the posterior pharyngeal wall, the degree and level of neoglottic closure during phonation (presence and place of the neoglottic bar and distance and intensity of contact between posterior and anterior wall), the pressure built up below the neoglottic bar during phonation (intraluminal pressure), the diameter of the pharynx (pharyngeal and esophageal volume and extension), previous or post-operative (chemo-)radiotherapy, and (the extent of) neck dissections [14,[16][17][18][19][20][21][22][23][24][25][26][27][28]. Although the extent of the surgical resection is primarly dictated by tumor extent, surgical techniques, such as neurectomy and upper esophageal myotomy, and the technique of pharynx (muscle) closure and type of reconstruction thus seem to be important phonosurgical aspects of TL.…”