Laryngeal electrode platform: an indwelling device for mobilizing the vocal cords

By passing electrical current across the laryngeal mucosa and esophageal wall, the recurrent laryngeal nerve can be stimulated, thereby mobilizing the vocal cords. In designing a device that would utilize this phenomenon, we theorized that stability, targeting, and mucosal contact could be maximized by an indwelling device that would conform precisely to the topography of the posterior larynx. In five dogs, molds of the hypopharynx and proximal esophagus were fashioned in vivo by injection of an alginate compound. From each mold was constructed a vinyl platform blanketed with electrodes. Each platform fit snugly in place, and could activate the nerve consistently in any of the dogs. With as little as 3 mA pulsatile current, use of specific electrodes enabled bilateral abduction, more than doubling the resting glottic aperture. Bilateral adduction was sometimes attainable. Such a platform may have use in visualizing subglottic lesions, diagnosing laryngeal movement disorders, and facilitating intubation and extubation.