Magnetic Laryngeal Reanimation as a Novel Treatment of Vocal Fold Immobility

Vocal fold paralysis may result from surgical complications, trauma, tumor, or unknown causes. When both cords are affected, paramedian fixation can lead to life-threatening obstruction. Current treatments, including tracheostomy, cordotomy, and arytenoidectomy, compromise speech and swallow function to maintain a safe airway. To preserve all three critical laryngeal functions, Otolaryngologists need a solution for bilateral vocal fold paralysis that restores motion. This study uses implantable electromagnet technology to create dynamic vocal fold movement in a proof-of-concept, preliminary model.

A prototype was constructed from a neodymium disk magnet and cylindrical solenoid electromagnet coupled to a battery and 3-way switch. The disk magnet was implanted in an ex vivo porcine larynx model lateral to the arytenoid, affixed with suture. The electromagnet was seated in a window cut in the thyroid cartilage.

By driving current in two directions through the electromagnet, the vocal fold was successfully moved towards and away from the electromagnet. The neutral vocal fold opening was 5.8 mm, and the maximal opening was 7.7 mm, representing a 31.4% increase in the cross-sectional area of the glottis.

This model demonstrated proof of concept of a magnetic laryngeal reanimation device. The full device will include a respiratory effort sensor and implantable processor to time the action of the magnets with respirations. There is currently no effective treatment to re-establish vocal fold motion in patients with vocal fold paralysis. This system has the potential to give patients with bilateral vocal fold paralysis a surgical option to restore vocal fold motion.