Vocal Cord Paralysis: Causes, Symptoms, and Treatment

What is Vocal Cord Paralysis?

Vocal cord paralysis is a neurological voice disorder in which one or both vocal folds fail to move properly due to impaired or interrupted nerve impulses to the laryngeal muscles. Your vocal cords, also called vocal folds, are two bands of muscle tissue located in your voice box (larynx) that vibrate to produce sound when you speak. When vocal cord paralysis occurs, these structures may not open for breathing or close effectively during speech and swallowing. This disruption affects not only voice production but also your body's ability to protect the airway during swallowing. The condition can range from mild weakness (paresis) to complete paralysis.

Causes of Vocal Cord Paralysis

Vocal cord paralysis causes vary widely, from surgical complications to underlying medical conditions. The condition develops when the recurrent laryngeal nerve or superior laryngeal nerve becomes damaged, compressed, or interrupted. These nerves control the muscles responsible for vocal cord movement.

Surprisingly, nearly 20% of vocal cord paralysis cases remain idiopathic, meaning no specific cause can be identified despite thorough medical investigation. This uncertainty can be frustrating, but many patients still achieve successful treatment outcomes regardless of the underlying cause.

Common Causes of Vocal Cord Paralysis

• Neck or chest surgery, particularly thyroid, cardiac, or oesophageal procedures
• Stroke affecting brain regions controlling voice and swallowing
• Tumors in the brainstem, neck, chest, or thyroid region
• Traumatic injuries to the head, neck, or chest area
• Viral infections such as herpes simplex virus or bacterial infections such as Lyme disease
• Neurological conditions including multiple sclerosis, Parkinson's disease, or myasthenia gravis
• Inflammatory or autoimmune disorders affecting the laryngeal nerves or muscles (e.g., sarcoidosis, systemic lupus erythematosus)
• Birth trauma or congenital abnormalities in children
• Prolonged intubation during medical procedures

How Vocal Cord Paralysis Develops

Vocal cord paralysis develops when nerve pathways controlling vocal cord muscles become disrupted. The recurrent laryngeal nerve, which branches from the vagus nerve, travels a complex route through your chest before reaching your voice box. This lengthy pathway makes it vulnerable to injury during various medical procedures or due to tumor compression.

The onset can be sudden, such as immediately following surgery or trauma, or gradual, as with slowly growing tumors or progressive neurological diseases. When nerve damage is complete, true paralysis occurs. Partial nerve impairment results in vocal cord weakness, which may still significantly impact voice quality and swallowing safety.

Symptoms of Vocal Cord Paralysis

The severity and combination of vocal cord paralysis symptoms depend on whether one or both vocal cords are affected.

1. Hoarseness or breathy voice quality that persists beyond normal cold symptoms
2. Weak, ineffective cough that fails to clear secretions properly
3. Noisy breathing or high-pitched wheezing sounds (stridor)
4. Difficulty swallowing liquids or solids, with frequent choking episodes
5. Reduced vocal volume or inability to speak loudly
6. Frequent throat clearing or sensation of something stuck in the throat
7. Reduced airway protective reflexes during swallowing
8. Shortness of breath or rapid fatigue when speaking for extended periods

Early Signs of Vocal Cord Paralysis

• Subtle changes in voice quality, becoming more breathy or raspy than usual
• Mild swallowing difficulties, especially with thin liquids like water or tea
• Need to take frequent breaths during conversations
• Occasional coughing or choking while eating or drinking
• Persistent throat discomfort without obvious infection
• Reduced vocal endurance during phone calls or meetings

Complications of Vocal Cord Paralysis

The most serious complication of vocal cord paralysis is aspiration pneumonia, which occurs when food or liquids enter your lungs instead of your stomach. This potentially life-threatening condition develops because paralysed vocal cords cannot effectively seal your airway during swallowing.

Bilateral vocal cord paralysis poses additional risks, including severe breathing difficulties that may require emergency intervention. The inability to cough effectively also increases susceptibility to respiratory infections and compromises overall lung health.

Imaging & Diagnostic Tests for Vocal Cord Paralysis

• Laryngoscopy: The primary diagnostic test involving direct visualization of vocal fold movement using a flexible or rigid endoscope, or a mirror in selected cases
• Laryngeal electromyography (LEMG): This test records electrical activity in the laryngeal muscles to evaluate the pattern of nerve injury and potential for recovery.
• CT or MRI scans: Identify potential causes like tumours, laryngeal cancer, or structural abnormalities along nerve pathways
• Laryngeal biopsy for histopathological examination: Performed when lesions or masses are detected to rule out malignancy
• Complete Blood Count (CBC): Evaluates for infections or blood disorders
• Thyroid function tests: Detects thyroid disease as a potential underlying cause
• ESR test: Assesses inflammation levels in your body
• ANA test: Screens for autoimmune conditions affecting the larynx
• Myasthenia gravis profile: Excludes neuromuscular disorders causing vocal cord weakness

Treatment Options for Vocal Cord Paralysis

Vocal cord paralysis treatment depends on the underlying cause, severity of symptoms, and whether one or both cords are affected. Treatment goals focus on improving voice quality, ensuring safe swallowing, and maintaining adequate breathing. Here are some essential treatment methods recommended by The Journal of Pharmaceutical Research International:

Surgical Treatments for Vocal Cord Paralysis

• Medialization thyroplasty: Surgical placement of an implant to move the paralyzed vocal fold toward the midline, improving glottic closure and voice quality
• Vocal cord injection: Temporary or permanent fillers injected to bulk up the paralysed cord
• Arytenoid adduction: Repositioning of vocal cord cartilage to improve cord closure
• Reinnervation surgery: Attempts to restore nerve supply to paralysed muscles
• Tracheostomy: Creating an alternative airway opening in severe bilateral cases

Non-Surgical Treatments for Vocal Cord Paralysis

• Voice therapy: Specialized speech therapy techniques to optimize remaining vocal function
• Swallowing therapy: Training to reduce aspiration risk and improve swallowing safety
• Observation and serial monitoring: Appropriate in recent-onset or partial nerve injuries, allowing time for potential spontaneous recovery before surgery

Vocal Cord Paralysis in Children

Vocal cord paralysis in children may be present from birth (congenital) or develop following birth trauma, surgical procedures, or neurological conditions. Affected infants often present with weak crying, noisy breathing, feeding difficulties, and poor weight gain.

Pediatric cases require multidisciplinary management, taking into account airway size, growth, and neurodevelopmental factors. Some children recover spontaneously as their nervous system matures, while others may need surgical intervention or supportive care.

Vocal Cord Paralysis in Adults

Adult vocal cord paralysis most commonly results from surgical complications, particularly following thyroid or neck procedures. Tumours, neurological conditions, and trauma also contribute significantly to adult cases. However, many adult cases remain idiopathic despite thorough investigation.

Adults typically present with hoarseness, breathy voice quality, and swallowing difficulties. The impact on professional and social functioning can be substantial, making prompt evaluation and treatment essential for maintaining quality of life and preventing complications.

How to Prevent Vocal Cord Paralysis

Complete prevention of vocal cord paralysis isn't always possible, especially for idiopathic cases or those related to underlying medical conditions. However, certain measures can reduce your risk of developing this condition.

Careful surgical technique during neck, chest, or thyroid procedures significantly reduces the likelihood of nerve injury. Choosing experienced surgeons and discussing vocal cord paralysis risks before surgery helps you make informed decisions. Prompt treatment of infections and early diagnosis of tumors through regular health screenings also minimize potential complications. Avoiding neck and chest trauma by using seatbelts, helmets, and protective gear during contact sports reduces the risk of laryngeal nerve injury.

Conclusion

Understanding vocal cord paralysis empowers you to recognize symptoms early and seek appropriate medical care. At Metropolis Healthcare, we understand the importance of precise diagnostic testing in managing complex conditions like vocal cord paralysis. Our comprehensive portfolio of over 4,000 tests includes specialised blood work such as thyroid function tests, inflammatory markers, and autoimmune panels that help identify underlying causes.

Through our network of over 220 laboratories and 10,000 touchpoints across India, we bring accurate diagnostic testing directly to your home, ensuring convenient access to the services you need.

FAQs

What is vocal cord paralysis?

Vocal cord paralysis is a condition where one or both vocal cords cannot move properly due to nerve damage or dysfunction. This impairs voice production, swallowing safety, and airway protection, potentially leading to serious complications if left untreated.

How do you treat vocal cord paralysis?

Vocal cord paralysis treatment varies depending on the cause and severity. Options include voice therapy, surgical procedures like vocal cord injection or thyroplasty, and sometimes observation for spontaneous recovery.

Can vocal cord paralysis go away on its own?

Some cases of vocal cord paralysis may resolve spontaneously, particularly those caused by temporary nerve inflammation or mild injury. However, recovery typically occurs within the first few months, and persistent cases usually require medical intervention.

How long does it take to recover from vocal cord paralysis?

Recovery time varies significantly depending on the underlying cause and extent of nerve damage. Some patients recover within weeks to months, while others may have permanent paralysis requiring long-term management strategies and rehabilitation.

What causes vocal cord paralysis in children?

Vocal cord paralysis causes in children include birth trauma, congenital neurological conditions, surgical complications from cardiac or airway procedures, infections, and rarely, tumors.

References

• https://www.journaljpri.com/index.php/JPRI/article/view/6919
• https://pmc.ncbi.nlm.nih.gov/articles/PMC7669319/
• https://www.sciencedirect.com/science/article/abs/pii/S0892199716302247
• https://www.mayoclinic.org/diseases-conditions/vocal-cord-paralysis/diagnosis-treatment/drc-20378878