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Vocal cord paralysis is a disorder that occurs when one or both of your vocal cords don't open or close properly because nerve impulses to the muscles of your voice box are interrupted. Vocal cord paralysis is a disorder that can happen at any age.

The cause of vocal cord paralysis can indicate whether the disorder will likely improve over time or whether it is likely to be permanent. Symptoms of vocal cord paralysis can range from mild to life-threatening.

Treatments for vocal cord paralysis range from voice therapy to help you strengthen your vocal cords and improve your ability to speak, to surgical options, or both.

Vocal cord paralysis almost always results in a change to your voice. Your voice may be hoarse (croaky or rough) or breathy, as though you are exhaling excessive air when you speak. You also may notice that your voice has weakened. Other signs and symptoms may include:

• Shortness of breath
• Noisy breathing
• Choking or coughing while swallowing food, drink or saliva
• The need to take frequent breaths while speaking
• Inability to speak loudly
• Inability to "bear down" while lifting

If both of your vocal cords are affected (bilateral vocal cord paralysis), you may experience the symptoms above as well as significant problems with breathing.

Your vocal cords (also called vocal folds) are two elastic bands of muscle tissue covered by smooth mucous membranes. The vocal cords are located in your voice box (larynx), which is an assemblage of cartilage, muscle and mucous membranes situated between the base of your tongue and the top of your windpipe (trachea).

When functioning properly, the vocal cords remain apart, in an open position, enabling you to breathe easily. When you speak or sing, nerves signal your vocal cords to move toward each other and close. As air leaves your lungs, your vocal cords vibrate to produce sound.

In vocal cord paralysis, the nerve impulses to your voice box are interrupted, resulting in no movement (paralysis) of the muscle. This can affect breathing, eating and swallowing, and can cause mild to major voice changes.

There are many possible causes of vocal cord paralysis. The cause of the paralysis can indicate to your doctor whether the disorder will improve over time, or whether it's most likely permanent. However, in nearly half of all cases, doctors can't determine the cause. Known causes can include:

• Injury to the vocal cord during surgery. Surgery on or near your neck or upper chest can result in damage to the nerves that serve your voice box. Surgeries that carry a risk of damage include surgeries to the thyroid, esophagus, neck and chest.
• Neck or chest injury. Trauma to your neck or chest may injure the nerves that serve your vocal cords.
• Stroke. A stroke interrupts blood flow in your brain and may damage the part of your brain that sends messages to the voice box.
• Tumors. Tumors, both cancerous and noncancerous, can grow around the muscle and cartilage of your voice box and can cause vocal cord paralysis.
• Inflammation. The cricoarytenoid joint, which connects two pieces of cartilage within your voice box, can become inflamed due to arthritis or during surgery. While technically not a paralysis but instead a fixation of the cricoarytenoid joint, the symptoms and signs mimic paralysis. In addition, some viral infections can cause inflammation and damage to the laryngeal nerves themselves.
• Neurological conditions. If you have certain neurological conditions, such as Parkinson's disease or multiple sclerosis, you may experience vocal cord paralysis; however, these conditions are more likely to cause vocal cord weakness than complete paralysis.

If you have hoarseness that lasts more than three weeks, or if you notice any unexplained voice changes or discomfort, contact your doctor.

If you've gone to your regular doctor with a concern about your voice, he or she may refer you to an expert in the field. Vocal cord paralysis is usually diagnosed by an ear, nose and throat specialist (otolaryngologist). Your doctor will ask about your symptoms and lifestyle, listen to your voice, and ask you how long you've had voice problems. You may undergo these diagnostic tests:

• Endoscopy. Your doctor may look at your vocal cords using a thin, flexible tube (endoscope) with a light at one end and a viewing piece or camera at the other. The endoscope allows your doctor to view your vocal cords directly or on a video monitor to determine whether one or both vocal cords are affected, as well as the movement and position of the vocal cords.
• Laryngeal electromyography (LEMG). This test can confirm the diagnosis of vocal cord paralysis by measuring the electric currents in your voice box muscles. By measuring and looking at the pattern of the currents, your doctor can determine the degree of the problem and what types of treatment may be most effective. During this test, your doctor inserts small needles into your vocal cord muscles to measure the electric currents to the muscles while you perform a number of tasks that directly affect your voice box muscles.

Because a number of diseases may cause a nerve to be injured, you may need additional tests to identify the cause of the paralysis. Your doctor may suggest a consult with a neurologist or other doctor to rule out damage to nerves other than those to the voice box. Tests may include blood work, X-rays, computerized tomography (CT) scans, or magnetic resonance imaging (MRI) of the head, neck and chest.

Breathing problems associated with vocal cord paralysis can range from mild to life-threatening. Because vocal cord paralysis causes the opening to the airway to never completely open or close, complications may include choking or coughing while eating.

In addition, you may develop pneumonia if food and liquid are inhaled (aspirated) into your lungs, because your vocal cords cannot adequately close to protect your airway when swallowing.

Treatment of vocal cord paralysis depends on the cause, severity of symptoms and the time from the onset of symptoms. Treatment may include voice therapy, surgery, or both. In some instances, your voice may return to normal without treatment. For this reason, your doctor may delay surgery for up to a year and suggest voice therapy in the meantime.

Voice therapy
Voice therapy is often a first treatment option, especially if the cause of the condition is unknown. Even when nothing can be done about the nerve damage causing the paralysis, the function of the larynx can improve. In addition, doctors often recommend voice therapy after a surgical procedure to treat vocal cord paralysis.

For voice therapy, you meet with a speech language pathologist, also called a speech therapist. Therapy sessions involve exercises or other activities to strengthen your vocal cords, improve breath control during speech, or protect your airway during swallowing.

Surgery
Surgical treatments for vocal cord paralysis can improve your ability to speak and to swallow. Surgical options include:

• Bulk injection. To add bulk to the paralyzed vocal cord, a doctor who specializes in ear, nose and throat disorders (otolaryngologist) injects your vocal cord with a substance such as body fat, collagen or another approved substance, either through your mouth or through the skin of your neck. This added bulk brings the affected vocal cord closer to the middle of your voice box so that the functioning, moving vocal cord can make closer contact with the paralyzed cord when you speak or swallow. This can be done as an inpatient or outpatient procedure.
• Medialization thyroplasty. In this surgical procedure, your doctor moves a "window" of cartilage from the outside of your voice box inward, pushing the paralyzed vocal cord toward the middle of your voice box. Thyroplasty doesn't disturb the movement of the tissue that lines the vocal cord, which helps preserve the voice. This procedure is almost always done on an outpatient basis under local anesthesia with intravenous sedation.
• Tracheotomy. If both of your vocal cords are paralyzed (bilateral vocal cord paralysis), you may have trouble breathing if your vocal cords are in a closed position. This condition may require a surgical procedure called a tracheotomy, in which an incision is made in the front of your neck and a breathing tube is inserted through a hole (stoma) into the windpipe (trachea). Breathing then takes place through the tube, bypassing the immobilized vocal cords.

Vocal cord paralysis can be frustrating and sometimes debilitating, especially since your voice is so important to your personality. Speak to a speech therapist about things you can do to help you develop the skills you need to communicate. Even if you're not able to regain the voice you once had, speech therapy can help you learn effective ways to compensate.