Surgical Techniques for Glottal Airway Enlargement -Laterofixation of the Vocal Fold-

Abstract

Glottal airway enlargement is required to manage dyspnea due to bilateral vocal fold paralysis (BVFP). The method of vocal fold laterofixation reported by Ejnell et al. is relativly non-invasive and has been considered the first choice in cases of BVFP in recent years. We used a video-laryngoscope to obtain a better endolaryngeal view and a GORE-TEX® Soft Tissue Patch as a spacer between the thyroid lamina and the nylon knot to prevent loosening. Laryngeal pacing is a more dynamic and physiologic treatment approach than static airway enlargement procedures, such as laterofixation of the vocal fold. Laryngeal pacing is the application of functional electrical stimulation (FES) of the laryngeal abductor muscles. We evaluated the efficacy of FES in restoring glottal opening, ventilation, and exercise tolerance in a BVFP canine model. An implantable stimulator and deep brain stimulation electrodes were surgically implanted into both posterior cricoarytenoid (PCA) muscles in the animal, and the bilateral recurrent laryngeal nerves were sectioned and repaired. Beyond three months postoperatively, there was passive airway narrowing and further closure of the glottis during hypercapnia. The animal showed severe stridor and could only walk for one to two minutes on a treadmill. With the stimulation-on condition, the glottal area increased considerably, equaling that of a normally innervated animal. Exercise tolerance also returned to normal. Bilateral PCA stimulation offers a physiologic approach to restore ventilation to a normal level in cases of BVFP.