Vocal Cord Paralysis: Causes, Symptoms, and Treatment Options
Your voice may become hoarse for several reasons, including an infection, excessive speaking or throat irritation. However, a weak, breathy or persistently hoarse voice can sometimes indicate a condition known as vocal cord paralysis.
Vocal cord paralysis occurs when one or both vocal cords cannot move normally because the nerve signals controlling them have been disrupted. In addition to affecting the voice, the condition may cause swallowing difficulties and, in more serious cases, breathing problems.
What Is Vocal Cord Paralysis?
The vocal cords, also called vocal folds, are two bands of muscle tissue located inside the larynx or voice box. They open while you breathe, close while swallowing and vibrate when air passes through them to create sound.
When a vocal cord becomes paralysed, it may not open or close properly. Paralysis affecting one vocal cord is known as unilateral vocal cord paralysis, while paralysis affecting both is called bilateral vocal cord paralysis. Bilateral paralysis is less common but can cause serious breathing difficulties.
What Causes Vocal Cord Paralysis?
Vocal cord paralysis usually develops when the nerves that control the muscles of the voice box become damaged or stop functioning properly. Possible causes include:
Surgery Around the Neck or Chest
Operations involving the thyroid gland, parathyroid gland, oesophagus, neck or upper chest may occasionally affect the nerves connected to the vocal cords.
Neck or Chest Injuries
Trauma to the neck or chest can damage the larynx or the nerves controlling vocal cord movement.
Neurological Conditions
Stroke and certain neurological conditions, including Parkinson’s disease and multiple sclerosis, may interfere with the nerve signals sent to the voice box.
Tumours
Non-cancerous or cancerous growths in the neck, thyroid, chest, skull base or voice box may press against or damage the nerves controlling the vocal cords.
Infections
Certain viral or bacterial infections may cause inflammation or damage to the nerves supplying the larynx.
In some patients, no definite cause can be identified. This is referred to as idiopathic vocal cord paralysis.
Common Symptoms of Vocal Cord Paralysis
Symptoms can vary depending on whether one or both vocal cords are affected and where the paralysed cord is positioned.
Common signs include:
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Persistent hoarseness
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A weak, breathy or soft voice
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Difficulty speaking loudly
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Running out of breath while speaking
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Loss of vocal pitch or volume
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Frequent throat clearing
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A weak or ineffective cough
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Coughing or choking while eating or drinking
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Difficulty swallowing liquids
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Noisy breathing
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Shortness of breath
When the vocal cords do not close completely during swallowing, food or liquid may accidentally enter the airway. This can increase the risk of aspiration and related lung complications.
Sudden breathing difficulty, severe shortness of breath or noisy breathing requires immediate medical attention, particularly when both vocal cords may be affected.
How Is Vocal Cord Paralysis Diagnosed?
An ENT specialist will begin by reviewing the patient’s symptoms, medical history, recent surgeries and the duration of the voice change.
Tests may include:
Laryngoscopy
A thin, flexible camera is passed through the nose or mouth to examine the vocal cords and determine whether one or both are moving normally.
Videostroboscopy
This specialised examination provides a detailed view of vocal cord vibration, movement and closure during speech.
Laryngeal Electromyography
Laryngeal electromyography measures electrical activity in the muscles of the voice box. It may help evaluate nerve function and estimate the possibility of recovery.
Imaging and Blood Tests
CT scans, MRI scans, X-rays or blood tests may be recommended when the doctor needs to identify an underlying tumour, neurological condition, infection or other cause of nerve damage.
Treatment Options for Vocal Cord Paralysis
Treatment depends on the cause, duration and severity of the condition. The doctor will also consider whether the paralysis affects one or both vocal cords and whether the patient has difficulty speaking, swallowing or breathing.
Observation and Monitoring
Some patients experience gradual nerve recovery without permanent surgery. The ENT specialist may monitor vocal cord movement for several months while managing the patient’s symptoms.
Voice Therapy
Voice therapy is conducted by a trained speech-language pathologist. It may include exercises to improve breath control, strengthen voice production, reduce unnecessary muscle tension and help protect the airway while swallowing.
For some patients with mild symptoms, voice therapy may be sufficient. It may also be recommended before or after a surgical procedure.
Vocal Cord Injection
An injectable material may be placed into the paralysed vocal cord to add volume and move it closer to the centre of the voice box. This allows the functioning vocal cord to make better contact with it during speaking, swallowing and coughing.
Depending on the material used, the results may be temporary or longer-lasting.
Medialisation Thyroplasty
During medialisation thyroplasty, also known as medialisation laryngoplasty, an implant is placed inside the larynx to reposition the paralysed vocal cord closer to the centre. This can help improve voice strength and swallowing safety.
Vocal Cord Reinnervation
Reinnervation surgery connects a healthy nerve to the affected vocal cord muscle. The procedure aims to restore nerve signals and help maintain the strength and shape of the vocal cord muscle. Improvement may occur gradually over several months.
Treatment for Bilateral Vocal Cord Paralysis
When both vocal cords are paralysed, treatment primarily focuses on maintaining a safe airway. Procedures such as cordotomy or tracheostomy may be required when the vocal cords significantly restrict breathing.
When Should You Consult an ENT Specialist?
Consult an ENT specialist when hoarseness or voice weakness continues without a clear reason, particularly when it is accompanied by swallowing difficulty, choking, breathing problems or a recent neck or chest operation.
Early examination helps identify the cause and allows the specialist to recommend the most suitable treatment. With proper evaluation, voice therapy and appropriate medical or surgical care, many patients can experience meaningful improvements in their voice, swallowing and overall quality of life.
This information is intended for general awareness and should not replace an examination or personalised advice from a qualified medical professional.
