Vocal Cord Dysfunction
Vocal cord dysfunction
Definition
Vocal cord dysfunction (VCD) is a disorder that occurs when the vocal cords move toward each other when a person breathes, narrowing the airway and causing wheezing and difficulty breathing. VCD is also called paradoxical vocal cord motion (PVCM).
Description
Normally when an individual breathes in (inhales) or out (exhales) the vocal cords are drawn apart by the muscles of the larynx (voice box) to make a wider opening for air to move into or out of the lungs. In an individual with vocal cord dysfunction, instead of being drawn apart, the vocal cords move together, narrowing and partially blocking the airway. This is called adduction of the vocal cords. Adduction of the vocal cords happens most commonly during inhalation, although it can also happen during exhalation. As a result of the narrowed airways, the individual may cough , wheeze, feel short of breath, or make a high-pitched, harsh sound (called stridor ) with each breath.
VCD is often misdiagnosed as either asthma or exercise-induced bronchospasm. As a result, many individuals with VCD are treated with inhalers and steroids for asthma, which do not help control VCD and which have potentially harmful side effects.
Demographics
The number of people with VCD in the general U.S. population is unknown. The disorder often occurs in conjunction with asthma and is frequently a missed diagnosis. Several small studies have found that about 40 percent of individuals who have VCD also have asthma and that about 10 to 15 percent of individuals whose asthma does not respond to aggressive treatment (refractory asthma) actually have VCD.
VCD has been found in individuals as young as three and as old as 82. However, in adults it most often occurs between the ages of 20 and 40. In children it appears most often about age 14 or 15. VCD is much more common in females than in males. In children under 18, about 85 percent of individuals diagnosed with VCD are girls. In children, the disorder has a strong association with competitive sports and family orientation toward high achievement. In adults it has a strong association with anxiety and stress. This association with stress is present, but less frequent in children.
Causes and symptoms
VCD was first recognized in 1842, when it was thought that hysteria, a common designation at that time for several psychological conditions, brought about spasm of the muscles of the larynx. By 1900, it was generally accepted that VCD was the physical expression of stress or other psychological conditions. It was not until the 1980s that physicians began to revisit the assumptions about the disorder and examine more closely its physical causes. As of 2004, the causes of VCD was not completely clear.
In the early 2000s, it is thought that the disorder may have multiple causes and that some of the triggers may be different in children and adults. VCD appears to be associated with the following:
- injury to the brain cortex
- brainstem compression (mainly in children)
- Arnold-Chiari syndrome (mainly in children)
- gastroesophageal reflux disease (GERD; in children and adults)
- chronic sinus infection/postnasal drip
- strenuous exercise (often in children)
- exposure to inhaled irritants (smoke, toxic chemicals; mainly in adults)
- psychological causes (most obvious in adults)
- nerve injury during congenital heart disease surgery or other chest surgeries
- failure to respond to asthma treatments
VCD usually comes on suddenly. Between attacks, the individual can breathe normally. The symptoms of a VCD attack are varied, but most strongly imitate those of asthma. Its similarity to asthma, along with the fact that some people with VCD actually also have asthma, complicates diagnosis. Common signs and symptoms include the following:
- coughing (about 75% of individuals)
- wheezing
- stridor
- voice changes during an attack
- difficulty inhaling (most common)
- difficulty exhaling (less common; usually irritant-induced)
- panic, anxiety, fear of suffocating
- insufficient oxygen in the blood (hypoxia)
- chest tightness
- panting in short shallow breaths
- feeling like something is stuck in the throat
- skin turning blue
When to call the doctor
Immediate emergency medical assistance is essential whenever there are any signs of breathing difficulty.
Diagnosis
Diagnosis of VCD is quite difficult. VCD can mimic the symptoms of severe asthma, allergic reactions (anaphylaxis ), spasm of the larynx (laryngospasm), or a foreign object lodged in the throat. VCD is often a diagnosis of exclusion, which means that other possibilities are considered first, and when these are eliminated, VCD is considered. This may require a lot of testing.
The best way to determine if an individual has VCD is by doing a laryngoscopy. In a laryngoscopy, a slender, flexible tube containing a fiber optic camera is inserted through the nose and down the throat to the larynx. This examination allows the doctor to see the vocal cords and watch how and when they move.
Since between attacks the vocal cords appear to move normally, it is necessary to trigger an attack. Individuals cannot voluntarily produce symptoms of VCD, so they are usually exposed to an irritant or undergo an exercise stress test in order to bring on a VCD attack. The doctor then watches the vocal cords move. A classic finding is that the vocal cords move toward each other when the individual inhales, leaving a small triangular hole or chink at the back of the larynx. Individuals with asthma do not show this triangular chink.
Most people go through a series of other tests and often get other diagnoses, most commonly refractory (unresponsive) asthma, before they have a laryngoscopy and receive a definite diagnosis of VCD. Other tests that are frequently done to pinpoint or eliminate certain respiratory disorders include arterial blood gas values (to measure oxygen in the blood), pulmonary function tests (to measure lung capacity), with flow-volume loops (to measure the rate of air flow at different points in the breathing process). A methacholine provocation test, which stimulates a response in asthmatics, but not in persons with VCD, also helps narrow the diagnosis.
Treatment
Treatment consists of two phases, immediate (acute) and long term. Acute care often occurs in a hospital emergency room. The most important aspect of acute care is to see that the individual is breathing and getting enough oxygen. Sometimes heliox therapy is given. Heliox is a mixture of 20 to 30 percent oxygen and 70 to 80 percent helium. Because this mixture is less dense and more oxygen-rich than regular air, it is easier to inhale. If the individual is still not getting enough oxygen, it may be necessary to perform a tracheotomy. In this operation, a tube is inserted in the larynx so that air can bypass the blockage.
Long-term therapy begins by stopping any treatments for other diagnoses such as asthma, and treating any underlying conditions, such as brainstem compression or GERD, affecting the disorder. Airborne irritants are removed from the individual's environment as much as possible. Speech therapy and teaching abdominal breathing techniques have been quite successful in preventing VCD attacks. If an individual does not respond adequately to speech therapy, psychotherapy is recommended, as in many people anxiety and stress are linked to VCD attacks. People can learn relaxation techniques and work through problems causing stress and anxiety. Occasionally anti-anxiety drugs are prescribed.
KEY TERMS
Arnold-Chiari syndrome —A congenital malformation of the base of the brain.
Asthma —A disease in which the air passages of the lungs become inflamed and narrowed, causing wheezing, coughing, and shortness of breath.
Exercise-induced bronchospasm —A sudden contraction in the lower airway that causes breathing problems and is brought about by heavy exercise.
Gastroesophageal reflux disease (GERD) —A disorder of the lower end of the esophagus in which the lower esophageal sphincter does not open and close normally. As a result the acidic contents of the stomach can flow backward into the esophagus and irritate the tissues.
Laryngoscope —An endoscope that is used to examine the interior of the larynx.
Stridor —A term used to describe noisy breathing in general and to refer specifically to a high-pitched crowing sound associated with croup, respiratory infection, and airway obstruction.
In an experimental procedure, botulinum toxin (Botox) may be injected into the larynx. The drug paralyzes the muscle, making it impossible for the vocal cords to move across the airway. This technique appears to be successful but may require repeated injections as the toxin wears off. Another experimental device is a facemask that provides resistance when the individual inhales but not during exhalation. The resistance forces the person to breathe in more slowly and reduces stridor.
Alternative treatment
Some individuals have found biofeedback very helpful in controlling or moderating VCD attacks. Others have benefited from relaxation and mind control techniques.
Prognosis
The long-term outcome for VCD is not known and probably varies among individuals depends on the underlying cause of the disorder. Only a handful of people with VCD have been followed for 10 or more years, and all of them continued to have symptoms of the disorder. However, speech therapy and psychotherapy are often successful in reducing the number of attacks.
Prevention
Although the physical conditions that cause VCD cannot be prevented, individuals can be educated not to panic and to use certain breathing techniques when they begin to feel symptoms of VCD. In addition, airborne pollutants should be eliminated from the individual's environment. These steps can be somewhat successful in minimizing attacks.
Parental concerns
Parents have obvious reason to be concerned when their child has sudden breathing problems. Many children with VDC make multiple trips to the emergency room before the condition is correctly diagnosed. Many medical professionals are only marginally familiar with VCD, because this problem is much less common than asthma. Parents may want to suggest additional testing for VCD if their child is being treated for asthma without success.
See also Asthma; Stridor.
Resources
PERIODICALS
Leggit, Jeff. "Vocal Cord Dysfunction." American Family Physician 69 (March 1, 2004): 1045.
Perkins, Patrick J., and Michael J. Morris. "Vocal Cord Dysfunction Induced by Methacholine Challenge Testing." Chest 122 (December 2002): 1988–93.
Rundell, Kenneth W., and Barry A. Spiering. "Inspiratory Stridor in Elite Athletes." Chest 123 (February 2003): 468–74.
Truwit, Jonathon. "Pulmonary Disorders and Exercise." Clinics in Sports Medicine 22 (January 2003): 161–80.
ORGANIZATIONS
National Jewish Medical and Research Center. 1400 Jackson Street, Denver, CO 80206–2671. Web site: <www.njc.org/>.
WEB SITES
Buddiga, Praveen, and Michael O'Connell. "Vocal Cord Dysfunction." eMedicine Medical Library, October 27, 2003. Available online at <www.emedicine.com/med/topic3563.htm> (accessed December 3, 2004).
National Jewish Medical and Research Center. "Vocal Cord Dysfunction." Medfacts, July 15, 2004. Available online at <www.nationaljewish.org/medfacts/vocal.html> (accessed December 3, 2004).
Sidofsky, Carol. Can't Breathe? Suspect Vocal Cord Dysfunction. Available online at <www.cantbreathesuspectvcd.com> (accessed December 3, 2004).
Tish Davidson, A.M.
Vocal Cord Paralysis
Vocal Cord Paralysis
Definition
Vocal cord paralysis is the inability to move the vocal cords and the resulting loss of vocal cord function.
Description
The vocal cords are a pair of tough, fibrous bands that lie across the air column in the middle of the voice box. They assist three functions: breathing, swallowing, and speaking. When vocal cords vibrate, they produce sound, allowing us to speak. Vocal cords temporarily stop breathing to aid coughing and for expelling foreign objects. During swallowing, the vocal cords shut the airway so that food is not inhaled. When vocal cords are paralyzed, all three functions are affected.
The relaxed position of the vocal cords is halfway open. There is one set of muscles that closes them all the way and one set that opens them. Each set of muscles is controlled by a different nerve. Each nerve comes from a different direction—one from above and one from below (the recurrent laryngeal nerve). Vocal cords can either be partially paralyzed on one side or completely paralyzed on both sides.
Causes and symptoms
Vocal cord paralysis can result from injury, tumors, or surgery in the neck and upper chest. Brain tumors and stroke can also affect the nerves. Infectious diseases that damage nerves—like whooping cough, tetanus and polio—can also cause vocal cord paralysis. Vocal cord paralysis can also appear as a congenital defect. If congenital, the most frequent cause is a brain defect, which can often be effectively treated.
The most dangerous form of vocal cord paralysis is one that affects the opening function, controlled by the recurrent laryngeal nerve. If both vocal cords are paralyzed, breathing stops or becomes very labored. Fortunately, injury during trauma or surgery often involves only one side, but the congenital causes can damage both sides.
Vocal cord paralysis produces several symptoms.
- The voice is always affected; at best it is breathy and weak. At worst, it is not there at all. In infants, the cry can be weak. Older children will suppress laughing and coughing because it is hard to do.
- Swallowing may be hindered so that food ends up in the airway, causing violent coughing and often leading to pneumonia.
- Breathing is obstructed on inspiration, producing a condition known as stridor. Closing the airway while breathing in produces creaking noises in the throat and changes the shape of the chest. The breast bone is drawn inward, much more visibly in the flexible chest of a small child.
Diagnosis
The voice box must be observed during breathing to characterize the problem. A viewing instrument called a laryngoscope, either flexible or rigid, is passed through the nose or throat until the cords becomes visible. The motion of each cord can then be seen, and other problems in the area identified.
X rays, CT, or MRI scans of the skull may be done if a brain disorder is suspected.
Treatment
An adequate airway is immediately necessary, usually secured with an endotracheal tube in the windpipe. If a cure cannot be achieved, a permanent breathing hole (tracheostomy) is cut in the neck. Brain problems that are relieved within 24 hours usually allow the cords to regain their function. Care must be taken to assure that swallowing takes place normally.
Alternative treatment
Vocal cord paralysis can be addressed with constitutional homeopathy. This will work with the whole person, not just the symptoms, to help bring about healing. Botanical medicine and deep tissue massage to the area can also bring some resolution, although it may not be long term.
Resources
BOOKS
Ballenger, John Jacob. Disorders of the Nose, Throat, Ear, Head, and Neck. Philadelphia: Lea & Febiger, 1991.
KEY TERMS
Computed tomography (CT scan)— Computerized use of x rays to create images of internal organs.
Laryngoscope— A diagnostic instrument that is used to examine the interior of the larynx.
Magnetic resonance imaging (MRI)— Computerized use of magnetic fields and radiofrequency signals to create images of internal organs.
Recurrent laryngeal nerve— One of two offshoots of the vagus nerve that connect to the larynx. It is located below the larynx.
Stridor— A raspy sound that occurs during respiration when the airways are blocked.
Tracheostomy— Surgical opening in the neck to the trachea to aid respiration.
Voice box— The larynx.
Vocal Cord Nodules and Polyps
Vocal Cord Nodules and Polyps
Definition
Vocal cord nodules and polyps are noncancerous growths on the vocal cords that affect the voice.
Description
The vocal cords, located in the voice box in the middle of the neck, are two tough, fibrous bands that vibrate to produce sound. They are covered with a layer of tissue that is similar to skin. With use, this layer thickens. With heavy use, the thickening may localize, producing a nodule. Unlike skin, heavy usage over a short time may also produce polyps. A polyp is a soft, smooth lump containing mostly blood and blood vessels. A nodule is similar to a polyp, but tends to be firmer.
Causes and symptoms
Chronic infections caused by allergies and inhalation of irritants, such as cigarette smoke, may produce these lesions, but extensive use of the voice is the most common cause of vocal nodules and polyps. Nodules and polyps are more common in male children, female adolescents, and female adults. This may be due in part to the faster speed at which the cords vibrate to produce higher-pitched voices.
Voice alterations are most apparent in singers, who may notice the higher registers are the first to change. Hoarseness causes others to seek medical attention.
Diagnosis
The head and neck surgeon (otorhinolaryngologist) must see the vocal cords to diagnose these lesions. It is also important to confirm that there are not other problems instead of or in addition to these benign lumps. Other causes of hoarseness include throat cancers, vocal cord paralysis, and simple laryngitis. The cords can usually be seen using a mirror placed at the back of the tongue. More elaborate scopes, including a videostroboscope, allow better views while the cords are producing sounds.
A biopsy of a nodule or polyp will ensure they are not cancerous.
Treatment
Nodules usually only require voice therapy; less than 5% of nodules require surgery. Small polyps can be treated with voice therapy, but typically they are surgically removed.
Prognosis
Continued overuse of the voice will cause these lesions to regrow.
Prevention
Careful use of the voice will prevent most vocal cord nodules and polyps. Avoiding inhaled irritants, may also prevent nodules and polyps from forming.
Resources
BOOKS
Ballenger, John Jacob. Disorders of the Nose, Throat, Ear, Head, and Neck. Philadelphia: Lea & Febiger, 1991.
KEY TERMS
Laryngitis— Inflammation of the larynx (voice box).
Lesion— A wound or injury.
Otorhinolaryngologist— A physician specializing in ear, nose, and throat diseases. Also known as otolaryngologist.
VOCAL CORDS
vocal cords
vo·cal cords (also vo·cal folds) • pl. n. folds of membranous tissue that project inward from the sides of the larynx to form a slit across the glottis in the throat, and whose edges vibrate in the airstream to produce the voice.