[Effect of extent of glottal incompetence on phonation in excised canine larynx models]

Objective: To compare the acoustic signal, mucosal wave and aerodynamic parameter (phonation threshold pressure, PTP) under different sub-glottal pressure (SGP) on the excised canine models with different extent of glottal incompetence. Methods: Perturbation measures and nonlinear dynamic measures were applied to analyze the acoustic signal (jitter, shimmer), mucosal wave [frequency(F), amplitude(A), phase(P)] and PTP from our study including 11 excised canine larynges with different extent of glottal incompetence (0 mm, 1 mm, 2 mm, 3 mm, n=11, respectively) under 1-4 kPa sub-glottal pressure. Results: There were significant differences between different groups in jitter, shimmer, amplitude, frequency and PTP under various SGPs and extent of glottal incompetence (all P<0.05), inversely, there was no significant difference in P between groups (P>0.05). Jitter and shimmer changed obviously when the SGP increased to 3 kPa in the control group and GI 1 mm group. Jitter and shimmer changed obviously when the SGP increased to 2 kPa in the GI 2 mm and 3 mm groups. The F and A of mucosal wave increased with increasing SGP, decreased with increasing GI, and the P changed irregularly. There was statistically significant difference of PTP between different GI groups. Conclusions: The SGP and the extent of GI had obvious affection on the the acoustic signal, mucosal wave and aerodynamic parameters.