Implantable Active Artificial Larynx: Timing Evaluation of a Laboratory Prototype*

Total laryngectomy surgery consists in the removal of the larynx, and only allows to breath through a tracheostomy, where the trachea is permanently sewn on the anterior throat. Therefore, no air passes through the nose and mouth anymore, and restoring normal breathing would require to set the trachea back in place and to reproduce the closing mechanism of the trachea, which protects the airway during swallowing. In that regard, we seek to demonstrate the feasability of an implantable active artificial larynx, coupled with implanted sensors and real-time swallowing detection, and its speed constitutes the decisive aspect. Our previous works have shown that carefully chosen anatomical structure can provide qualitative signals and improved performances for a safe and early detection of swallowing. Therefore, as a proof a concept, the current paper focuses on its engineering aspects, that should allow to protect the trachea as fast as possible. We designed a laboratory prototype to estimate the operational uptime of such a system, and we showed that the real-time detection of swallowing, followed by the closure of the protective mechanism, can operate in less than 30 ms seconds. We then discuss the main avenues that would improve the implantability of such a system.