Arytenoid adduction

Procedure

• Local anesthesia is preferred for arytenoid adduction so that the voice can be tested during the procedure.
• A horizontal skin incision is made at the inferior border of the thyroid cartilage.
• A window is cut in the thyroid cartilage for a suture to be passed through later in the procedure.
• The strap muscles, pharynx, and larynx are dissected to expose the muscular process of the arytenoid cartilage.
• A permanent suture is passed through the muscular process.
• A tunnel is made in the thyroid cartilage and one end of the suture is passed through it.
• The suture is tied and secured to the window made in the thyroid cartilage.
• The vocal cords are observed endoscopically to ensure proper rotation of the arytenoid.
• The patient is asked to phonate to evaluate voice quality and the potential need for a concurrent thyroplasty.

Indications

Options for surgical treatment of vocal cord paralysis include vocal cord injection, medialization thyroplasty, and arytenoid adduction. Each of these techniques results in medialization of the paralyzed vocal cord. However, arytenoid adduction is preferred in cases where there is a large posterior glottal gap or vertical misalignment between the vocal folds. Arytenoid adduction is often performed at the same time as a medialization thyroplasty. Animal model studies suggest that combining the two procedures produces better outcomes than when performing either alone.

Posterior glottal gap

The paralyzed vocal cord may rest close to or far from the midline. An extremely laterally positioned vocal cord can result in a large posterior glottal gap - an opening between the two vocal cords even when the functioning vocal cord is fully medialized. Vocal cord injection is ineffective for closing a large glottal gap. Arytenoid adduction is more effective than medialization thyroplasty for closing a posterior gap. It has been suggested that this is because arytenoid adduction directly rotates the arytenoid cartilage and thus more actively medializes the posterior aspect of the vocal cord.

Vertical glottal gap

The paralyzed vocal cord may rest on a different plane than the opposite vocal cord. This results in a vertical gap between the two vocal cords that cannot be resolved using vocal cord injection or medialization thryoplasty. The suture placed in the arytenoid adduction procedure mimics the action of the lateral cricoarytenoid muscle and pulls the vocal process of the arytenoid cartilage medially and inferiorly. Thus arytenoid adduction can correct the vertical position of an elevated vocal cord.

Outcomes

Arytenoid adduction with or without medialization thyroplasty significantly improves quality of life for patients with vocal cord paralysis. Subjective outcome measures of voice quality include the Grade, Roughness, Breathiness, Asthenia, Strain (GBRAS) voice scale, Voice Handicap Index, and closure of the glottic gap. Objective outcome measures include mean and maximum phonation time, phonatory airflow, and signal-to-noise ratio. Arytenoid adduction produces improvements in all of these parameters.

Disadvantages and complications

Arytenoid adduction is more technically challenging than either vocal cord injection or medialization thyroplasty and has a high learning curve. Increased incidence of complications have been reported for arytenoid adduction compared to medialization thyroplasty.

Potential complications include:

• Wound infection
• Edema
• Hematoma
• Vocal cord spasms

Intubation and/or tracheotomy may be required as a result of these complications.