Mucosal wave characteristics in simulated vocal ovepressure. A preliminary study using LVS & HSDP with analysis by kymography, P-FFT & Nyquist plots

Chapter 20

  • Krzysztof Izdebski
  • Ronald R. Ward
  • Lydia Hyde
  • Yuling Yan
  • Matthew Blanco
Keywords: HSDP, LVS, female voice, VoP, dysphonia, mucosal wave, glottic cycle, GAW, PFFT, Nyquist plots


In this preliminary HSDP report we focus on in vivo observations of not only of the glottic region, but on supraglottic laryngeal posturing during simulated production of vocal overpressure (VoP) as well. Resultant data were analyzed with spatio-temporal algorithms capable of describing vibration patterns of vocal folds (VF), multi-line kymograms, spectral P-FFT analysis, and Nyquist spatio-temporal plots. Results reveal that supraglottic contraction assists in prolonged closed phase of the vibratory cycle in VoP and that prolonged closed phase is long in VoP, but not as long as in vocal fry. In our opinion, these findings lead to a better differential diagnosis, and hence to a more efficacious treatment.