Overview
Laryngeal recurrent nerve palsy generally refers to unilateral or bilateral vocal cord movement abnormalities caused by motor nerve disorders in the larynx. It is not an independent disease, but a clinical manifestation of a variety of local or systemic diseases, mostly caused by neck trauma, thyroid surgery, tumors and so on. The disease can be categorized into central and peripheral according to the site of lesion, and peripheral is more common. Since the laryngeal recurrent nerve is a branch of vagus nerve and accepts the intersection of cerebral cortical motor area, the left side of vagus nerve and laryngeal recurrent nerve has a longer path, so the right side is more prone to injury.
Etiology
This disease can be caused by thyroid surgery, neck trauma, tumors (thyroid tumor, mediastinal tumor, lung cancer, etc.).
Symptoms
1. In unilateral incomplete paralysis, there is occasional hoarseness, and shortness of breath may occur with strenuous exercise. Laryngoscopy shows that the vocal cords of the affected side can not be adducted, and the vocal folds can be closed during vocalization.
2. In bilateral incomplete paralysis, laryngeal obstruction may occur. Laryngoscopy shows that the vocal cords of both sides cannot be abducted, close to the midline position, and the vocal folds can still be closed when voicing.
3. In unilateral complete paralysis, there is hoarseness, fatigue, and a sense of air leakage. Laryngoscopy shows that the affected vocal folds are fixed in the paracentral position, and the vocal folds do not close well during vocalization.
4. Bilateral complete paralysis, hoarseness and weakness of voice, speaking effort, can not be sustained, there may be dyspnea after activity, easy to choke. Laryngoscopy shows that both vocal cords are located in the paracentral position, with loose edges, fluttering up and down with the respiratory airflow.
Examination
1. Physical examination
Different degrees of hoarseness and muffled voice can be heard. In the case of bilateral paralysis, different degrees of inspiratory dyspnea can be seen on palpation.
2. Laryngoscopy
Indirect laryngoscopy, fiberoptic laryngoscopy can see unilateral or bilateral spoon-like cartilage and vocal cord movement disorder, vocal cord flaccidity in the form of arch; vocal cord mucosa color and surface structure is normal. Stroboscopic laryngoscopy can observe the weakening of the mucosal wave of the affected side of the vocal folds.
3. Laryngeal electromyography
It can show the degree of damage to the recurrent laryngeal nerve.
4.Voice spectrum analysis
Analyzes the degree of hoarseness and vocal fold leakage.
Diagnosis
Diagnosis can be made on the basis of clinical manifestations and signs, combined with laryngoscopy and laryngeal electromyography. For etiologic diagnosis, other auxiliary examinations, such as ultrasound of the neck and thyroid, chest X-ray, esophageal X-ray imaging, etc., are also needed to help clarify the etiology.
Treatment
1. Tracheotomy
Tracheotomy should be performed as early as possible to improve the respiratory status of patients with respiratory distress caused by bilateral vocal cord paralysis.
2. Treatment of etiology
For those who have a clear cause, give appropriate treatment and actively relieve the cause of the disease.
3. Laryngeal recurrent nerve recovery treatment
(1) Drug therapy: local and systemic application of neurotrophic drugs, glucocorticoids and vasodilating drugs, which have a certain auxiliary effect on the recovery of nerve function.
(2) Non-pharmacological treatment: You can go to voice rehabilitation clinic for voice training. It is necessary to prohibit spicy food, smoking and alcohol, and avoid all stimulation of the throat diet.
(3) Surgical treatment: For those who have surgical indications, laryngeal recurrent nerve exploration, nerve anastomosis, nerve myotis transplantation, hypoglossal nerve laryngeal recurrent nerve anastomosis, phrenic nerve laryngeal recurrent nerve anastomosis is the most ideal method to restore the autonomic movement of the vocal folds and to treat laryngeal recurrent nerve palsy.
4.Treatment to restore and improve laryngeal function
The following treatments are feasible for those who have been observed for more than one year and have no possibility of recovery of nerve function:
(1) For unilateral recurrent laryngeal nerve palsy, submucosal adipose tissue filling of the vocal folds and thyroid chondroplasty are feasible, so that the vocal folds can be shifted inward to improve the voice.
(2) For bilateral laryngeal recurrent nerve palsy, one side of the spoon-like cartilage resection or vocal cord abduction displacement fixation is feasible to improve respiratory function.