G. Paul Moore lecture: lessons in phonosurgery

Preliminary investigation of adjustable balloon implant for type I thyroplasty

OBJECTIVE

We present the adjustable balloon implant (ABI), a novel implant to be used in type I thyroplasty for the treatment of vocal fold paralysis. The ABI offers the same medialization provided by other implants, but can easily be catered to individual patient anatomy as well as modified postoperatively without the need for a revision thyroplasty.

STUDY DESIGN

Repeated measures with each larynx serving as its own control.

METHODS

Medialization thyroplasty (MT) with the ABI was performed on five excised canine larynges. Mucosal wave, aerodynamic, and acoustic parameters were measured for three conditions: normal; right vocal fold paralysis; and paralysis with the ABI.

RESULTS

Insertion of the ABI resulted in significant decreases in both phonation threshold pressure and phonation threshold flow. Perturbation parameters of percent jitter and percent shimmer were also significantly decreased and restored to normal levels. Signal-to-noise ratio was significantly increased to the normal level as well. The mucosal wave was preserved after implant insertion.

CONCLUSIONS

This preliminary experiment showing significant improvements in aerodynamic and acoustic parameters demonstrates the potential of the ABI as a thyroplasty implant. Effective medialization and preservation of the mucosal wave combined with postoperative adjustability makes it a potentially valuable clinical device.

Multiparameter comparison of injection laryngoplasty, medialization laryngoplasty, and arytenoid adduction in an excised larynx model

OBJECTIVES/HYPOTHESIS

Evaluate the effect of injection laryngoplasty (IL), medialization laryngoplasty (ML), and ML combined with arytenoid adduction (ML-AA) on acoustic, aerodynamic, and mucosal wave measurements in an excised larynx setup.

STUDY DESIGN

Comparative case study using ex vivo canine larynges.

METHODS

Measurements were recorded for eight excised canine larynges with simulated unilateral vocal fold paralysis before and after vocal fold injection with Cymetra. A second set of eight larynges was used to evaluate medialization laryngoplasty using a Silastic implant without and with arytenoid adduction.

RESULTS

IL and ML led to comparable decreases in phonation threshold flow (PTF), phonation threshold pressure (PTP), and phonation threshold power (PTW). ML-AA led to significant decreases in PTF (P = .008), PTP (P = .008), and PTW (P = .008). IL and ML led to approximately equal decreases in percent jitter and percent shimmer. ML-AA caused the greatest increase in signal-to-noise ratio. ML-AA discernibly decreased frequency (P = 0.059); a clear trend was not observed for IL or ML. IL significantly reduced mucosal wave amplitude (P = 0.002), whereas both ML and ML-AA increased it. All procedures significantly decreased glottal gap, with the most dramatic effects observed after ML-AA (P = 0.004).

CONCLUSIONS

ML-AA led to the greatest improvements in phonatory parameters. IL was comparable to ML aerodynamically and acoustically, but caused detrimental changes to the mucosal wave. Incremental improvements in parameters recorded from the same larynx were observed after ML and ML-AA. To ensure optimal acoustic outcome, the arytenoid must be correctly rotated. This study provides objective support for the combined ML-AA procedure in tolerant patients.

Collagen Injection as a Supplement to Arytenoid Adduction for Vocal Fold Paralysis

Objectives:

Dysphonia associated with vocal fold paralysis can persist even after successful medialization procedures, including arytenoid adduction. It is hypothesized that laryngeal collagen injection could improve phonation following arytenoid adduction in selected patients. Our objective was to evaluate how collagen injection could result in measurable improvements in vocal function and voice quality.

Methods:

Forty patients with unilateral vocal fold paralysis who had undergone arytenoid adduction underwent transoral injection of non—cross-linked bovine dermal collagen by means of indirect laryngoscopy and a curved injection device. A control group of 40 patients underwent arytenoid adduction but not collagen injection. The patients' voice quality was assessed perceptually with the GRBAS scale, and vocal function was assessed by acoustic and aerodynamic measures (maximum phonation time and transglottal DC flow). The relative glottal area was also assessed by videostroboscopy.

Results:

Significant improvements in vocal function and voice quality were observed with collagen injection for those patients who did not achieve satisfactory glottal competence with arytenoid adduction alone. Glottal area measurements revealed that glottic insufficiency was significantly reduced after arytenoid adduction as well as after collagen injection.

Conclusions:

The findings suggest that collagen injection could be an effective supplementary treatment for improving voice following arytenoid adduction. It has the advantage of being a minimally invasive outpatient office procedure. The long-term efficacy of the procedure should be explored.

Sulcus vocalis: a review

Sulcus vocalis is described as a groove at the free edge of the vocal fold. Different types have been described: sulcus type I is superficial and may be considered as moreless physiologic. Sulcus type IIa corresponds to a kind of vergeture along the margin of the vocal fold. Its deepness is variable but sulcus vergeture may involve deeper layers of the lamina propria. Sulcus type IIb or pounch may be considered as an open cyst. Sulcus lead to a complex glottic dysfunction with, in the same time, a glottal leakage responsible for the breathy component of the dysphonia and a stiffness of the free edge responsible for the roughness. Diagnosis may be difficult even with the help of stroboscopy and finally is sometimes done only under general anesthesia. Etiology remains controversial and the authors present arguments for each theory, acquired or congenital. Treatment options include phonosurgery and speech therapy but phonosurgery gives results often disappointing and surgical treatment must be indicated prudently and patient must be intensively informed on what he or she can expect from the treatment that is mainly an increase of the loudness of the voice.