Electrical stimulation of vocal cords with impaired mobility

Current surgical techniques helping patients with vocal cord impaired mobility involve the exposure of the endings of the recurrent laryngeal nerve or the exposure of the opening muscle of the larynx. Thereby, other muscles have to be cut, and vessels and nerves in the vicinity may be damaged causing an impaired mobility of the larynx during swallowing and an impaired sensitivity of mucous membranes with an increased risk of foreign body aspiration. Furthermore, scarring tissue may reduce stimulated movements in long-term tests. To improve the electrical stimulation method of the laryngeal muscles, MED-EL Elektromedizinische Geräte GmbH is developing a pacemaker to stimulate the vocal cords in humans and to improve patients current situation. Correct placing of the stimulating electrode inside the target muscle without decreasing the muscle's mobility is one of the most critical steps for functional electrical stimulation devices. This book shows the characteristics of a minimal- invasive Electrode Insertion Tool to stimulate vocal cords in patients with vocal cord impaired mobility. It includes the design, development and manufacturing of this prototype.