| The most succcessful method of voice and speech rehabilitation after laryngectomy is tracheo-esophageal phonation with a shunt valve. Female laryngectomees and laryngectomees with a hypotone pharyngo‑esophageal (PE) segment however, tend to have severe problems accepting their often weak and low‑pitched tracheo‑esophageal (TE) shunt voice. The objective of the project is development and evaluation of a sound producing shunt valve to improve the voice of these patients. The study is based upon previous developments within the European Eureka project "Artificial larynx" (EU 723), and upon numerical simulation models developed in the Department of BioMedical Engineering of the University of Groningen. The prototype alternative sound source consists of a vibrating silicone lip, incorporated in a regular Groningen shunt valve. Prototypes of this pneumatic sound source have been tested in vitro and in vivo, using perceptual voice‑quality tests, intelligibility tests and registration of aerodynamic and acoustic voice parameters using a newly developed data acquisition system, resulting in clear improvement of the voice in half of the patients. Low‑pitched and noisy vibrations of the patients= PE segment, additionally to the sound of the prosthesis and a suboptimal flow/frequency correlation, were the main problems in the non‑successful patients. Based upon these experiences and analyses new prototypes have been developed and are presently tested in vitro, as preparation to in vitro testing in laryngectomized patients. |
