Objective: To evaluate the effects of neurostimulation with the laryngeal pacemaker (LP) system in patients with bilateral vocal fold paralysis (BVFP) in terms of voice quality and respiratory function.
Study design: Feasibility study, first-in-human, single-arm, open-label, prospective, multicenter study with group-sequential design and 6-month follow-up period, as described in details in our previous publication.
Methods: Nine symptomatic BVFP subjects were unilaterally implanted with the LP system at three study sites in Germany and Austria. Subjective and objective voice function, spirometric parameters other than peak expiratory/inspiratory flow (PEF/PIF), and PEF-meter self-assessment were evaluated pre- and 6 months postimplantation.
Results: In general, the LP system did not considerably change the voice quality of the implanted patients. Only the sound pressure level range improved significantly 6 months postimplantation (P = 0.018). The LP system implantation did not affect the glottal closure configuration, the duration of the closed phase, and the mucosal wave of the implanted side. The evaluated spirometric parameters were not significantly affected by laryngeal pacing, whereas PEF meter self-assessment showed a stable and significant (P = 0.028) improvement of the PEF within a week upon activation of the LP system.
Conclusion: Neurostimulation with the LP system results in an immediate and stable PEF improvement, without negative effects on the voice quality. The PEF meter self-assessment confirmed the spirometry results of the PEF. The stimulated abduction did not affect the glottal closure during phonation. These results should be confirmed in larger and more homogenous patient cohorts.
Level of evidence: 2b Laryngoscope, 127:1838-1844, 2017.
Keywords: Bilateral vocal fold paralysis; first-in-human; laryngeal pacing; neurostimulation; prospective study; spirometry; voice.
© 2016 The American Laryngological, Rhinological and Otological Society, Inc.