Parametric Study and Numerical Simulation of Artificial Vocal Folds for Oesophageal Insertion

Background : Total laryngectomy results in the removal of the vocal folds, leading to permanent loss of natural speech. Current interventions, such as the electrolarynx and sound-producing voice prostheses (SPVP), provide lim ited phonation restoration. We propose a novel artificial vocal fold design af f ixed to a tracheoesophageal puncture (TEP) and implanted in the esophagus. This investigation assesses whether these artificial vocal folds, constrained by esophageal dimensions, can restore natural speech characteristics by analyzing key acoustic parameters. The findings provide data for future enhancements of the prosthesis examined in this study. Methods : Aninvitroparametricinvestigationwasconductedtoassessartifi cial vocal folds, constrained by esophageal dimensions, without evaluating full TEP integration. The study examined three primary factors: diameter, thick ness, and material elasticity, analyzing their effects on sound-related parame ters such as fundamental frequency (f0) and loudness. Experiments were per formedusingphysicalsiliconmodels,complementedbynumericalsimulations for validation. Results : Despite size limitations, the artificial vocal folds generated sound spectra comparable to human speech. The f0 ranged from 87 to 250 Hz, suit able for both male and female voices. Loudness measurements ranged from 53 to 67dB,aligningwithtypicalspeechlevels. Theparametricstudyrevealedrela tionships between modelparametersandsoundcharacteristics, indicating that increasedelasticityledtohigher f0,whilegreaterthicknessresultedinincreased maximum loudness. Numerical simulations corroborated these experimental outcomes. Conclusions : This research indicates that esophageal-implanted artificial vocal folds offer a promising approach for restoring phonation. Future inves tigations should build upontheseinitial findingsbytestingtheentireprosthetic device in vivo and exploring biosignal-based control mechanisms to optimize vocal fold function.