Name of the Procedure:

Chemodenervation of muscle(s); larynx, unilateral, percutaneous (e.g., for spasmodic dysphonia), includes guidance by needle electromyography, when performed

Summary

Chemodenervation of the larynx is a medical procedure used to treat spasmodic dysphonia, a voice disorder. This is done by injecting botulinum toxin (commonly known as Botox) into the muscles of the larynx. A needle electromyography (EMG) is often used to guide the injection.

Purpose

The procedure aims to relieve the symptoms of spasmodic dysphonia, which includes involuntary spasms of the vocal cords causing interruptions in speech and strained or strangled voice quality. The goal is to improve voice quality and reduce vocal strain.

Indications

• Spasmodic dysphonia, particularly when it affects one side of the larynx.
• Severe voice strain and interruption in speech patterns.
• Failure of other treatments, such as voice therapy, to provide relief.

Preparation

• Patients may be advised to avoid certain medications that can affect bleeding and clotting.
• Fasting for a few hours prior to the procedure may be recommended.
• A thorough medical history and vocal assessment will be conducted.
• Pre-procedure diagnostic tests may include a laryngoscopy.

Procedure Description

1. The patient is positioned comfortably, often seated or semi-reclined.
2. Topical anesthetic may be applied to numb the throat area.
3. A fine needle is inserted into the targeted laryngeal muscles using needle electromyography (EMG) for precise localization.
4. Botulinum toxin is injected into the muscles.
5. The needle is removed and the patient is monitored briefly for any immediate reactions.

Duration

The entire procedure typically takes 30-45 minutes.

Setting

This procedure is often performed in an outpatient clinic or a specialized ENT (Ear, Nose, and Throat) office.

Personnel

• Laryngologist or ENT specialist
• Nurse or medical assistant
• Occasionally, an anesthesiologist if sedation is needed

Risks and Complications

• Temporary swallowing difficulties or hoarseness.
• Bleeding or infection at the injection site.
• Allergic reaction to the medication.
• Vocal weakness or breathy voice, usually temporary.

Benefits

• Significant reduction in the severity of voice spasms.
• Improved voice quality and ease of speaking.
• The effects are often noticeable within days.

Recovery

• Patients can usually go home shortly after the procedure.
• Voice rest might be recommended for a day or two.
• Full recovery and optimal voice quality typically occur within a week.
• A follow-up appointment may be scheduled to assess the outcome.

Alternatives

• Voice therapy with a speech-language pathologist.
• Surgical intervention, such as selective laryngeal adductor denervation-reinnervation.
• Medications for muscle relaxation, though they are generally less effective.

Patient Experience

During the procedure, patients may feel slight discomfort or a pinching sensation when the needle is inserted. Post-procedure, mild soreness or hoarseness is common. Pain management is usually minimal, often requiring only over-the-counter pain relievers.