The iValve Hands-Free Speech Valve for Laryngectomized Patients. In Vitro Test of a Novel Device of Revolutionary Design

摘要

Background. Speech valves help restore speech after surgical removal of the larynx (laryngectomy). Laryngectomized Patients breathe through an artificial opening (tracheostoma) in the neck. A shunt valve is routinely inserted between oesophagus and trachea to restore speech. At closure of the stoma with a finger, exhaled air is rerouted into the oesophagus, which will vibrate and form the new voice. Manual closure of the stoma attracts attention, requires one free hand and is unhygienic. Therefore automatic, hands-free speech valves are preferred. Present valves automatically close upon strong exhalation and open again when the pressure drops. This method wastes valuable air during closure and pressure should be maintained during speech, making long sentences or pauses impossible. The new iValve closes at strong inhalation. In speech mode, inhalation mid sentence is now made possible. The patient can speak almost as natural, pausing and whispering at will. The iValve automatic inhalation valve is a full silicone rubber, hands-free speech valve. The switching mechanism consists of a silicone rubber bi-stable valve shell. A prototype was tested in vitro.Method. 6 iValve prototype versions were tested in vitro at different settings. Closing flows, Opening pressures and air flow resistances were measured and compared with physiological values and the air flow resistance of two commercially available valves.Results. The iValve operates within physiological pressures and flows. Air flow resistance in breath mode was good, yet higher than the two commercial valves. Resistance in speech mode was above physiological air flow resistance.Conclusions. The iValve works and can be adjusted within physiological ranges. Pressures and flows can be independently controlled. Air flow resistance in speech mode should, and can, be decreased. The full silicone rubber mechanism is a viable novel design approach. The iValve offers a more intuitively useable alternative with more dynamic speech.