OVERVIEW

What is vocal cord paralysis?

Vocal cord paralysis, also known as laryngeal paralysis, refers to dysfunction caused by damage to the nerves controlling the vocal cords, leading to impaired movement of one or both vocal cords, paralysis of the laryngeal muscles, and the vocal cords remaining in a paramedian, lateral, or midline position.

Vocal cord paralysis is usually caused by tumors, trauma, inflammation in the brain, neck, or chest, as well as various systemic diseases. These conditions can compress or damage the recurrent laryngeal nerve and superior laryngeal nerve that control the vocal cords, resulting in different symptoms.

Symptoms may include hoarseness, weak voice, rough voice, shortened vocal duration, air leakage when coughing, difficulty breathing, choking while eating or drinking, and difficulty expelling phlegm.

Is vocal cord paralysis common?

Not very common.

What are the types of vocal cord paralysis?

• Recurrent laryngeal nerve paralysis: Further classified into unilateral incomplete paralysis, unilateral complete paralysis, bilateral incomplete paralysis, and bilateral complete paralysis.

• Superior laryngeal nerve paralysis

• Mixed laryngeal paralysis

SYMPTOMS

What are the common manifestations of vocal cord paralysis?

• Unilateral incomplete paralysis: Short-term hoarseness.

• Unilateral complete paralysis: Hoarseness, easy fatigue, shortened voice duration, and air leakage during coughing.

• Bilateral incomplete paralysis: Difficulty breathing (especially during inhalation) with no obvious hoarseness.

• Bilateral complete paralysis: Hoarse and weak voice, effortful speech, whispering-like sound, inability to sustain speech, shortness of breath, frequent aspiration and choking, difficulty expelling phlegm, and wheezing during breathing.

• Superior laryngeal nerve paralysis: Inability to produce high-pitched sounds, rough and weak voice, shortened voice duration, loss of laryngeal sensation, and susceptibility to aspiration pneumonia.

• Mixed laryngeal paralysis: Significant hoarseness.

What serious consequences can vocal cord paralysis cause?

• Difficulty breathing or even respiratory distress.

• Aspiration pneumonia.

CAUSES

What Causes Vocal Cord Paralysis?

• Tumors: Malignant tumors in the nasopharynx, skull base, neck, or chest, as well as metastatic lymph node enlargement in the neck, can invade the vagus nerve or recurrent laryngeal nerve, leading to vocal cord paralysis. Common tumors include thyroid tumors, malignant lymphomas, carotid artery aneurysms, neurogenic tumors, invasive thyroid cancer, aortic aneurysms, mediastinal tumors, lung cancer, esophageal cancer, etc.

• Inflammation: Diseases such as diphtheria, syphilis, and influenza can cause peripheral neuritis of the recurrent laryngeal nerve.

• Surgical complications: Surgeries involving the neck, chest, or skull base, as well as tracheal intubation, may damage the recurrent laryngeal nerve or vagus nerve. Examples include thyroid and parathyroid surgeries, carotid endarterectomy, cardiothoracic surgeries, and anterior cervical discectomy.

• Trauma: Such as skull base fractures, neck injuries, chest trauma, or laryngeal trauma.

• Systemic diseases: Conditions like polio, amyotrophic lateral sclerosis, diabetic neuropathy, myasthenia gravis, and demyelinating diseases.

• Toxins and medications: Poisoning from organophosphates, lead, arsenic, or ethanol, as well as neurological side effects of vinca alkaloid chemotherapy drugs, may cause vocal cord paralysis.

• Cricoarytenoid joint fixation: Rheumatoid arthritis can lead to bilateral cricoarytenoid joint fixation, resulting in vocal cord paralysis.

Is Vocal Cord Paralysis Contagious?

No, it is not contagious.

Is Vocal Cord Paralysis Hereditary?

No, it is not hereditary.

DIAGNOSIS

How is vocal cord paralysis diagnosed?

Doctors can diagnose vocal cord paralysis through indirect laryngoscopy or fiberoptic laryngoscopy, combined with symptoms and medical history.

What tests are needed for vocal cord paralysis?

Fiberoptic laryngoscopy is required: It can reveal various types of vocal cord paralysis during breathing and phonation, and in some cases, vocal cord shrinkage or wavy edges may be observed.

Which diseases can vocal cord paralysis be easily confused with?

• Acute laryngitis: Significant hoarseness, an infectious condition lasting less than 3 weeks, often accompanied by runny nose, cough, and sore throat. Laryngoscopy shows mucosal edema and congestion of the vocal cords, with normal bilateral vocal cord movement.

• Chronic laryngitis: Long-term hoarseness and dry throat discomfort. Laryngoscopy reveals swollen, thickened vocal cords with normal bilateral movement.

• Vocal cord nodules/polyps: Persistent hoarseness. Laryngoscopy shows small protrusions or smooth, reddish polypoid tissue on the vocal cords, with normal bilateral movement.

• Laryngeal foreign body: History of foreign body inhalation, hoarseness, severe coughing. Neck lateral X-ray and laryngoscopy can detect the foreign body.

• Laryngeal diphtheria: Slow onset, hoarseness, and lethargy. Laryngoscopy reveals gray-white pseudomembranes on the laryngeal mucosa, with diphtheria bacilli found in secretions. Bilateral vocal cord movement is normal.

• Laryngeal tuberculosis: Low-grade fever, cough, throat pain, and weak hoarseness. Laryngoscopy shows pale, edematous laryngeal mucosa with irregular shallow ulcers. Bilateral vocal cord movement is normal. Chest X-ray reveals pulmonary tuberculosis lesions.

• Laryngeal syphilis: Hoarseness and difficulty breathing. Laryngoscopy displays dark red ulcers with sharp edges on the laryngeal mucosa. Bilateral vocal cord movement is normal. Syphilis serology is positive.

TREATMENT

Which department should I visit for vocal cord paralysis?

Generally, you should first visit the ENT (Ear, Nose, and Throat) department or consult the relevant department based on the cause.

What are the treatment options for vocal cord paralysis?

• Medication: Includes neurotrophic drugs, glucocorticoids, and vasodilators. For example, nimodipine may improve recovery rates in patients with acute (lasting less than 4 months) idiopathic or iatrogenic vocal cord paralysis.

• Surgical treatment: Includes laryngeal injection augmentation, thyroplasty, laryngeal nerve anastomosis, nerve implantation, neuromuscular pedicle transplantation, tracheotomy, vocal cord lateralization, and partial resection of the posterior vocal cord and arytenoid cartilage.

• Voice therapy.

• Physical therapy: Includes infrared, ultraviolet, ultrashort wave, and electrical stimulation.

Can vocal cord paralysis heal on its own?

If the nerve is bruised or stretched but not severed, or if the paralysis is caused by idiopathic factors (e.g., viral infection), vocal cord function may recover spontaneously.

Can vocal cord paralysis be completely cured?

It depends on the cause. Some cases can be fully cured, while others may only achieve functional improvement without complete restoration.

Is follow-up necessary for vocal cord paralysis? How is it done?

Follow-up is required. Within 6 months to 1 year, monthly check-ups may be needed to monitor the recovery of laryngeal function.

DIET & LIFESTYLE

What should patients with vocal cord paralysis pay attention to in daily life?

• Avoid smoking and alcohol, and stay away from spicy or irritating foods as well as harmful gases and dust.

• For those experiencing aspiration or choking, it is recommended to reduce liquid intake and consume more paste-like, thick foods to lower the risk of choking or aspiration.

• If vocal cord paralysis is caused by a throat infection, temporary voice rest or minimal speaking is advised to allow the vocal cords to recover, helping reduce inflammation and promote natural healing.

• For weakened voice due to vocal cord paralysis, practice breath-holding exercises while vocalizing repeatedly.

PREVENTION

Can vocal cord paralysis be prevented? How to prevent it?

Vocal cord paralysis is caused by nerve compression or damage due to other diseases, making it difficult to completely prevent its occurrence. However, measures can be taken to minimize its likelihood.

• Actively treat the diseases listed above that may lead to vocal cord paralysis.

• Avoid poisoning from organophosphorus pesticides, lead, arsenic, ethanol, etc.