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DictionarySeevocalvocal cord paralysis
Vocal Cord Paralysis DefinitionVocal cord paralysis is the inability to move the vocal cords and the resulting loss of vocal cord function.DescriptionThe 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 symptomsVocal 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.
DiagnosisThe 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.TreatmentAn 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 treatmentVocal 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.ResourcesBooksBallenger, John Jacob. Disorders of the Nose, Throat, Ear, Head, and Neck. Philadelphia: Lea & Febiger, 1991.Key termsComputed 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 paralysis Audiology Inability of one or both vocal folds (cords) to move because of brain or nerve damage. See Phonation. |