Vocal Cord Paralysis

Overview

Vocal cord paralysis occurs when the nerves that control the muscles of the vocal cords are damaged, so one or both vocal cords cannot move normally. The vocal cords need to open for breathing, close for swallowing to protect the airway, and come together to produce voice, so paralysis can affect all three functions.

Most often only one vocal cord is affected, which mainly causes voice problems. When both vocal cords are paralyzed, breathing can be seriously affected, which may be an emergency. Vocal cord paralysis has many possible causes, and treatment depends on the cause, how many cords are involved, and how much the voice, swallowing, and breathing are impaired.

The nerves that move the vocal cords travel a long path from the brain through the neck and chest, which exposes them to injury at many points, for example during surgery or from a tumor along their route. Identifying where and why the nerve is damaged is an important part of evaluation. Because the vocal cords do more than produce sound, paralysis can also make it harder to protect the airway during swallowing, raising the risk of food or liquid going down the wrong way.

Symptoms

Symptoms depend on whether one or both vocal cords are affected. They may include:

• A breathy, weak, or hoarse voice
• Difficulty speaking loudly or for long periods
• Choking or coughing while eating or drinking, especially with liquids
• A weak cough
• The need to take frequent breaths while speaking
• Noisy breathing or shortness of breath, particularly if both cords are involved

When both vocal cords are paralyzed near the midline, breathing difficulty can be severe and may be life-threatening, requiring urgent care.

Causes

Vocal cord paralysis results from damage to the nerves supplying the voice box. Common causes include:

• Surgery: Operations on the neck or chest (such as thyroid, neck, or chest surgery) can injure the nerves.
• Injury: Trauma to the neck or chest, or pressure from a breathing tube.
• Tumors: Growths in the neck or chest that press on or invade the nerves.
• Infections and inflammation: Certain viral infections can affect the nerves.
• Neurological conditions and stroke: Diseases affecting the nerves or brain.

In some cases no cause is found, which is called idiopathic vocal cord paralysis.

Risk Factors

• Recent neck or chest surgery
• Neck or chest injury
• Tumors of the neck, chest, or brain
• Certain neurological diseases
• Stroke
• Some viral infections

Diagnosis

An ENT specialist diagnoses vocal cord paralysis by examining the voice box and looking for the underlying cause. Evaluation may include:

• Laryngoscopy: Viewing the vocal cords with a small camera to see whether they move.
• Imaging: CT or MRI of the neck and chest to look for tumors or nerve injury along the nerve's path.
• Laryngeal electromyography: Testing the electrical activity of the voice box muscles in some cases.
• Swallow evaluation: To check for swallowing difficulty and aspiration risk.

Treatment

Treatment depends on the cause, the number of cords affected, and the impact on voice, swallowing, and breathing. Some cases improve on their own over months. Options include:

• Voice therapy: Working with a speech-language pathologist to strengthen and improve the voice and protect swallowing.
• Treating the underlying cause: Such as addressing a tumor or infection.
• Injection or surgery for one-sided paralysis: Procedures to move the paralyzed cord toward the midline, improving voice and reducing choking.
• Airway procedures for two-sided paralysis: When both cords are paralyzed and breathing is affected, surgery to open the airway, or a temporary tracheostomy, may be needed.

Because some recovery can occur over time, treatment is often individualized and may be staged.

When to See a Doctor

See a doctor for a persistent change in your voice, choking when eating or drinking, or a chronically weak voice. Seek emergency care immediately if you have:

• Difficulty breathing, noisy breathing, or shortness of breath
• Choking that blocks the airway
• Severe coughing and choking with eating or drinking
• Bluish lips or gasping for air

Breathing difficulty, especially with paralysis of both cords, is a medical emergency.

Related Topics

Frequently Asked Questions

References

1. National Institute on Deafness and Other Communication Disorders (NIDCD). Vocal fold paralysis.
2. American Academy of Otolaryngology–Head and Neck Surgery.
3. MedlinePlus, U.S. National Library of Medicine. Vocal cord disorders.