Principles of Vocal Fold Augmentation

Abstract

■ Vocal fold augmentation is a commonly used surgical treatment for glottic insufficiency.

■ Key differences between vocal fold augmentation and laryngeal framework surgery:

- Vocal fold augmentation is less effective at closing large (3 mm or greater) glottal gaps, especially in the posterior membranous region of the vocal folds

- Vocal fold augmentation may be less precise than framework surgery

- Vocal fold augmentation is however, a more minimally invasive approach, and can be carried out in a clinic-based setting.

■ Vocal fold augmentation is appropriate in a variety of clinical settings, but is commonly used in the following situations:

- Temporary correction for unilateral vocal fold paralysis

- Trial correction for glottal insufficiency (as a diagnostic measure)

- Permanent correction of vocal fold atrophy (as seen in presbyphonia), vocal fold paresis (unilateral and bilateral), unilateral vocal fold paralysis

- Adjunctive vocal fold augmentation after laryngeal framework surgery (“touch up”)

- Glottic insufficiency due to vocal fold scarring/ soft tissue loss

■ A variety of injectable substances are available for vocal fold augmentation, and can be categorized into temporary (2–6 months) and long-acting/permanent (2 years or more).

- Temporary injection substances include:

· Bovine gelatin (Gelfoam, Surgifoam)

· Collagen-based products (Zyplast, Cosmoplast/ Cosmoderm, Cymetra)

· Carboxymethylcellulose (Radiesse Voice Gel)

· Hyaluronic acid gel (Restylane, Hyalaform)

- Long-lasting injection substances include:

· Autologous fat

· Calcium hydroxylapatite (Radiesse)

· Teflon

■ Local anesthesia is generally preferred with vocal fold augmentation (peroral or percutaneous approach), so that the patient’s voice can be used as a constant source of feedback during the procedure (Chaps. 33 and 34).

■ Augmentation is directed at the posterior and midmembranous vocal fold, along the lateral vocal fold (superior arcuate line), and at a depth of 3–5 mm.

■ Injection into the superficial lamina propria (Reinke’s space) is to be avoided.

■ Overinjection (15–30%) is recommended to compensate for resorption of the water-based component present in most injectable substances. The exception to this rule is autologous lipoinjection, which requires substantial overcorrection.