Laryngeal paralysis is the result of damage to the tenth cranial nerve and its branches and can be unilateral or bilateral. In the context of speech therapy and/or surgery, laryngeal paralysis is readily treatable in the majority of cases.
What is laryngeal paralysis?
Laryngeal paralysis is a partial or complete paralysis of the laryngeal muscles associated with restricted or malpositioned movement of the vocal cords and/or glottis (glottis). As a rule, laryngeal paralysis is due to damage to the vagus nerve (tenth cranial nerve) and its two branches (superior laryngeal nerve and recurrent laryngeal nerve). A paralysis of the superior laryngeal nerve causes a reduced ability to stretch the vocal cords via a failure of the cricothyroid muscle, which severely limits the articulation of high-pitched sounds, while a failure of the recurrent laryngeal nerve results in a loss of respiratory mobility of the affected vocal cord. In addition, hoarseness manifests to varying degrees depending on the position of the affected vocal cord. In bilateral laryngeal paralysis, the focus is on respiratory distress, which is more pronounced the narrower the glottis. Damage to the vagus nerve, on the other hand, can lead to complete failure of the laryngeal muscles with paralysis of the muscles of the pharynx and soft palate, and is accompanied by marked voice disturbance as well as dysphagia.
Causes
Various causes affecting the vagus nerve and its branches can lead to laryngeal paralysis. In most cases, laryngeal paralysis is due to surgical procedures in the neck (including thyroid surgery, esophageal surgery, laryngoscopy), which increase the risk of injury to the recurrent laryngeal nerve (recurrent nerve palsy). In addition, various tumors (bronchial carcinoma, esophageal carcinoma, schwannoma, Garcin syndrome), infectious-toxic causes (herpes zoster, poliomyelitis, toxins, drugs), congenital impairments (hydrocephalus, spina bifida, Arnold-Chiari syndrome), and immunologic factors (Guillain-Barré syndrome) can cause laryngeal paralysis. Central laryngeal paralysis may manifest as a result of lesions of the central motor nerve pathways and is manifested by abnormal vocal cord movements, often suggestive of neurological conditions associated with dysarthria (central speech disorders) (including multiple sclerosis, Wallenberg syndrome). In rare cases, laryngeal paralysis cannot be attributed to any cause (idiopathic laryngeal paralysis).
Symptoms, complaints, and signs
Laryngeal paralysis is manifested by characteristic symptoms such as hoarseness, abnormal breath sounds, and shortness of breath. In severe cases, the affected person loses his or her voice. This is usually preceded by difficulty swallowing, an irritating cough, and occasionally pain. Symptoms may be unilateral or bilateral and may vary in severity. In mild laryngeal paralysis, there are only whistling breathing sounds and mild respiratory problems that subside after a few days. In severe paralysis, temporary voice loss may occur. In addition, any nerve damage may cause coughing attacks and problems swallowing. Bilateral damage to the laryngeal nerve can be life-threatening. Acute respiratory distress is then possible, associated with circulatory problems, hypoxia of the body and panic attacks. In general, laryngeal paralysis causes an irritating cough, sore throat and the typical foreign body sensation. Many sufferers experience a scratching sensation in the throat. If food debris gets into the lungs, it can lead to pneumonia. Pneumonia is associated with other health problems and is initially manifested by malaise, fever and indefinable pain in the lungs. If laryngeal paralysis is treated early, the signs of the disease soon weaken. In the absence of therapy, a life-threatening condition may develop.
Diagnosis and course
Laryngeal paralysis can be diagnosed on the basis of characteristic clinical signs (hoarseness, cadaval position, attenuated cough thrust, inspiratory stridor, loss of voice, and dyspnea in bilateral paralysis). The diagnosis is confirmed by an ENT medical examination with laryngeal and glottic endoscopy.Nerve function tests can detect impairment of the nerves. Diagnostic imaging techniques (computed tomography, magnetic resonance imaging, x-ray or sonography) provide information about tumors as well as other underlying factors. Differentially, laryngeal paralysis should be differentiated from myogenic (myopathy of the vocalis muscle, myastenia gravis pseudoparalytica) as well as articular (interarytenoid fibrosis, ankylosis of the cricoarytenoid joint) impairments. With early diagnosis and timely initiation of therapy, laryngeal paralysis generally has a good prognosis, and approximately two-thirds of paralysis symptoms resolve within six to eight months.
Complications
Significant complications can occur with paralysis of the larynx, known as recurrent paresis. These depend entirely on the position of the paralyzed vocal fold, whether the paralysis is unilateral or bilateral, and the tension and oscillatory capacity of it. The paralysis is particularly dangerous if both vocal cords are paralyzed and are also in the middle position (median). Then they close the entrance to the trachea and respiratory distress occurs. It may be necessary to arrange for a tracheotomy and to provide the patient with a tracheal cannula through which he can then breathe. However, this extreme case rarely occurs. More common are unilateral paralyses. If recurrent paralysis occurs, there is loss of the healthy voice. Prompt voice therapy can prevent long-term damage. However, paralysis may persist. However, the healthy vocal cord side is able to compensate so that the paralysis is no longer audible. Without treatment, the voice is more likely to sound hoarse, toneless and rough for a long time. The diseased voice not infrequently poses a major problem in communication at work. In addition to impaired vocal function, difficulty swallowing and difficulty clearing the throat are among the most common complications of laryngeal paralysis.
When should you see a doctor?
If there is a persistent change in vocalization, a doctor should be consulted. If there are impairments in the usual color of the voice or the strength of the vocalization, a visit to the doctor is necessary. If the affected person can only whisper or make barking sounds, a doctor is needed to determine the cause. If there is hoarseness, inability to speak, or a persistent scratchy feeling in the throat and pharynx, a doctor should be consulted. If there are whistling noises when breathing, an irritating cough, and sputum when coughing, a doctor should be consulted. In case of complaints of the swallowing act, a refusal to eat or a decrease in the usual intake of fluids, a doctor must be consulted. There is a risk of malnutrition of the organism, which in severe cases may end with the premature death of the patient. Disturbances of respiratory activity, a feeling of tightness in the throat or interruptions of breathing must be clarified by a doctor. In case of shortness of breath and simultaneous palpitations, immediate consultation of a physician is recommended. In severe cases, an emergency physician should be alerted. If the patient feels ill, suffocates or suffers from dizziness, a doctor should be consulted. If the frequency of swallowing increases sharply when food is ingested, a physician is needed.
Treatment and therapy
Therapeutic measures for laryngeal paralysis depend on the severity of the impairment and the underlying cause. Thus, in the case of laryngeal paralysis associated with unilateral vocal cord loss, early voice therapy is generally used, if necessary to prevent muscle atrophy, in combination with faradization (low-frequency stimulation current) of the affected nerves. Here, the logopedic therapy aims to compensate the affected vocal cord with the healthy one. In some cases, anti-inflammatory and decongestant medications are also recommended. If the laryngeal paralysis is caused by a bacterial infection, antibiotic therapy is indicated. If these treatment measures do not lead to the desired success (after about 6 months at the earliest), phonosurgical measures such as thyroplasty or vocal fold augmentation may be indicated, in the course of which a renewed complete closure of the vocal folds or glottis is produced by a median displacement of the affected vocal cord in order to ensure improved vocalization and loudness.If bilateral laryngeal paralysis is present, surgical measures (endolaryngeal laser resection of the stellate cartilage, laterofixation) are aimed at optimizing respiratory function by laterally displacing the paralyzed vocal cords to widen the glottis. In addition, bilateral laryngeal paralysis due to acute respiratory distress may require a tracheostomy (tracheotomy) followed by insertion of a speaking tube.
Outlook and prognosis
Whether and to what extent affected individuals can provide relief from their symptoms themselves depends on both the cause and the severity of the condition. The psychological burden of laryngeal paralysis should not be underestimated. Taking advantage of psychotherapeutic therapy or exchanging experiences within the framework of a self-help group helps to look positively into the future again. The voice therapy carried out as part of the treatment of unilateral vocal cord loss can also be intensified by the patient at home with targeted exercises. Likewise, a drug therapy can be supported with homeopathic agents under certain circumstances. However, due to the risk of interactions, this must be clarified in advance with the attending physician. After about six months, it is decided whether the selected measures have had the desired success or whether a surgical intervention may be necessary. If this is the case, the patient must ensure the necessary bed rest postoperatively and must not strain his voice in the first few days and speak as little as possible. To relieve the surgical wound, the patient must initially resort to liquid food. This should also be neither too hot nor too cold or too strongly flavored. The attending physician will draw up an individual diet plan for this in advance, which will also ensure an adequate supply of vitamins and nutrients.
Prevention
Laryngeal paralysis can be prevented to a certain extent, depending on the underlying cause. For example, infectious diseases of the upper respiratory tract should be treated early and consistently to avoid affecting the nerves supplying the laryngeal muscles. In addition, surgical procedures in the neck region, especially thyroid surgery, should be performed only with appropriate injury prevention measures.
Aftercare
The extent to which follow-up care is necessary depends on the nature and outcome of the initial therapy. Basically, a distinction must be made here between conservative methods and surgical intervention. Outpatient therapies take place until the best possible result has been achieved. If the patient is free of symptoms, no follow-up care is necessary. If there are limitations, doctors try to keep these as low as possible with medication or further therapies. Since it is not uncommon for the ability to speak to suffer, psychological and social problems often result. Psychotherapy then leads to more stability. Long-term treatment may be indicated in the case of a severe form of the disease. If, on the other hand, a surgical intervention has taken place, the surgeon initially takes over the aftercare. During the first few months, the surgeon checks the resilience of the voice and the breathing capacity several times. This is followed by a long-term check-up, which is usually scheduled once a year. A local ear, nose and throat specialist can also perform this. In this, the lingering symptoms of laryngeal paralysis are discussed. If complications are suspected, laryngoscopy and imaging may be performed. Inasmuch as laryngeal paralysis has been caused by tumor disease, a detailed follow-up plan is drawn up. This is intended to ensure that a new cancer is detected as early as possible. Doctors hope this will provide optimal treatment options.
What you can do yourself
The steps sufferers of laryngeal paralysis can take themselves depend on the severity of the impairment, the underlying causes and the type of treatment. In the case of laryngeal paralysis associated with unilateral vocal cord loss, voice therapy is usually performed, which can be supported by voice exercises at home. Drug treatment may be supported by natural remedies. The responsible physician must decide whether homeopathic remedies may be used. After an operation, the usual measures apply, such as rest and bed rest. The voice must not be strained in the first days after an operation.The diet shortly after surgery should consist of liquid food, which should also not be too irritating, spicy, hot or cold. Usually, the doctor will work with the patient to create an individualized diet. Since laryngeal paralysis is often a considerable burden for those affected, therapeutic counseling is advisable. The patient should contact the attending physician for this. The latter can establish contact with a specialist and, if necessary, also suggest a suitable self-help group.
