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Comparative Study
. 2010 Feb;119(2):125-32.
doi: 10.1177/000348941011900210.

Multiparameter analysis of titanium vocal fold medializing implant in an excised larynx model

Affiliations
Comparative Study

Multiparameter analysis of titanium vocal fold medializing implant in an excised larynx model

Rachel E Witt et al. Ann Otol Rhinol Laryngol. 2010 Feb.

Abstract

Objectives: We evaluated the efficacy of the titanium vocal fold medializing implant (TVFMI) for the treatment of unilateral vocal fold paralysis (UVFP) on the basis of acoustic, aerodynamic, and mucosal wave measurements in an excised larynx setup.

Methods: Measurements were recorded on 8 excised canine larynges with simulated UVFP before and after medialization with a TVFMI.

Results: The phonation threshold flow (p < 0.001) and phonation threshold power (p = 0.008) decreased significantly after medialization. The phonation threshold pressure also decreased, but this difference was not significant (p = 0.081). Jitter (p = 0.005) and shimmer (p = 0.034) decreased significantly after medialization. The signal-to-noise ratio increased significantly (p = 0.05). Differences in mucosal wave characteristics were discernible but not significant. The phase difference between the normal and paralyzed vocal folds (p = 0.15) and the amplitude of the paralyzed vocal fold (p = 0.78) decreased. The glottal gap decreased significantly (p = 0.004).

Conclusions: The TVFMI was effective in achieving vocal fold medialization, improving vocal aerodynamic and acoustic characteristics of phonation significantly and mucosal wave characteristics discernibly. This study provides objective, quantitative support for the use of the TVFMI in improving vocal function in patients with UVFP.

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Figures

Figure 1
Figure 1
Schematic diagram of excised larynx experimental apparatus.
Figure 2
Figure 2
Excised canine larynx with simulated right vocal fold paralysis before (A) and after (B) TVFMI insertion.
Figure 3
Figure 3
Phonation threshold power measurements before and after TVFMI insertion. PTW significantly decreased from 1987 cmH2O*mL/s to 503 cmH2O*mL/s after medialization (p=0.008).
Figure 4
Figure 4
Signal-to-noise ratio measurements before and after TVFMI insertion. SNR significantly increased from 1.96 to 6.36 after medialization (p=0.05).
Figure 5
Figure 5
Percent jitter measurements before and after TVFMI insertion. Percent jitter significantly decreased from 7.15% to 3.58% after medialization (p=0.005).
Figure 6
Figure 6
Percent shimmer measurements before and after TVFMI insertion. Percent shimmer significantly decreased from 27.80% to 13.69% after medialization (p=0.034).
Figure 7
Figure 7
Glottal gap measurements before and after TVFMI insertion. Glottal gap significantly decreased from 68.98 to 30.75 after medialization (p=0.004).

References

    1. Havas T, Lowinger D, Priestley J. Unilateral vocal fold paralysis: causes, options and outcomes. Aust N Z J Surg. 1999 Jul;69(7):509–13. - PubMed
    1. Dedo HH, Urrea RD, Lawson L. Intracordal injection of Teflon in the treatment of 135 patients with dysphonia. Ann Otol Rhinol Laryngol. 1973 Sep-Oct;82(5):661–7. - PubMed
    1. Isshiki N, Morita H, Okamura H, Hiramoto M. Thyroplasty as a new phonosurgical technique. Acta Otolaryngol. 1974 Nov-Dec;78(5-6):451–7. - PubMed
    1. Gardner GM, Parnes SM. Status of the Mucosal Wave Post Vocal Cord Injection Versus Thyroplasty. Journal of Voice. 1991 Mar;5(1):64–73.
    1. Dedo HH. Injection and removal of Teflon for unilateral vocal cord paralysis. Ann Otol Rhinol Laryngol. 1992 Jan;101(1):81–6. - PubMed

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