Vocal cord paralysis is a voice disorder that occurs when one or both of the vocal cords (or vocal folds) do not open or close properly.
The vocal cords are two elastic bands of muscle tissue located in the larynx (voice box) directly above the trachea (windpipe). The vocal cords produce voice when air held in the lungs is released and passed through the closed vocal cords, causing them to vibrate. When a person is not speaking, the vocal cords remain apart to allow the person to breathe.
Vocal cord paralysis may be caused by:
- Head trauma
- A neurologic insult such as a stroke
- A neck injury
- Lung or thyroid cancer
- A tumor pressing on a nerve
- A viral infection
In older people, vocal cord paralysis is a common problem affecting voice production. People with certain neurologic conditions, such as multiple sclerosis or Parkinson’s disease, or people who have had a stroke may experience vocal cord paralysis. In many cases, however, the cause is unknown.
Vocal cord paralysis is a common disorder, and symptoms can range from mild to life threatening. Someone who has vocal cord paralysis often has difficulty swallowing and coughing because food or liquids slip into the trachea and lungs. This happens because the paralyzed cord or cords remain open, leaving the airway passage and the lungs unprotected.
People who have vocal cord paralysis experience abnormal voice changes, changes in voice quality, and discomfort from vocal straining. For example, if only one vocal cord is damaged, the voice is usually hoarse or breathy. Changes in voice quality, such as loss of volume or pitch, may also be noticeable. Damage to both vocal cords, although rare, usually causes people to have difficulty breathing because the air passage to the trachea is blocked.
There are several methods for treating vocal cord paralysis, among them surgery and voice therapy. In some cases, the voice returns without treatment during the first year after damage. For that reason, doctors often delay corrective surgery for at least a year to be sure the voice does not recover spontaneously. During this time, the suggested treatment is usually voice therapy, which may involve exercises to strengthen the vocal cords or improve breath control during speech. Sometimes, a speech-language pathologist must teach patients to talk in different ways. For instance, the therapist might suggest that the patient speak more slowly or consciously open the mouth wider when speaking.
Surgery involves adding bulk to the paralyzed vocal cord or changing its position. The added bulk reduces the space between the vocal cords so the nonparalyzed cord can make closer contact with the paralyzed cord and thus improve the voice.
Treating people who have two paralyzed vocal cords may involve performing a surgical procedure called a tracheotomy to help breathing. In a tracheotomy, an incision is made in the front of the patient’s neck and a breathing tube (tracheotomy tube) is inserted through a hole, called a stoma, into the trachea. Rather than breathing through the nose and mouth, the patient now breathes through the tube. Following surgery, the patient may need therapy with a speech-language pathologist to learn how to care for the breathing tube properly and how to reuse the voice.