Vocal Cord Paralysis: Symptoms, Causes, Diagnosis and Treatment

01What

What is vocal cord paralysis?

The vocal cords are two bands of muscle in the larynx. They open to let air in and close to protect the airway when swallowing and to make sound. Each is controlled by the recurrent laryngeal nerve, a long nerve that loops down into the chest before returning to the voice box. If this nerve is injured or compressed, the cord becomes weak (paresis) or immobile (paralysis) and cannot move properly. See cuerdas vocales dañadas (Spanish).

02Symptoms

Symptoms

• Breathy, weak or hoarse voice; reduced volume and a voice that tires quickly.
• Voice breaks or lower pitch, difficulty projecting.
• Choking or coughing when swallowing, particularly thin liquids; food or drink “going down the wrong way”.
• Shortness of breath or running out of breath when talking.
• Noisy breathing (stridor), especially with bilateral paralysis.
• Frequent throat clearing and a feeling of something in the throat.
• Recurrent chest infections from aspiration.
• Symptoms often begin suddenly after surgery or illness, or gradually.

03Causes

Causes

• Surgical injury: thyroid or parathyroid surgery, neck or chest surgery, heart or lung surgery, and spinal surgery on the front of the neck.
• Intubation or prolonged ventilation.
• Tumours in the neck, thyroid, lung, oesophagus or chest that compress or invade the nerve.
• Viral infections affecting the nerve (a common idiopathic cause).
• Neurological conditions: stroke, Parkinson’s disease, multiple sclerosis, myasthenia gravis.
• Trauma to the neck or chest.
• Idiopathic, with no cause found in a significant proportion.
• Because tumours can be a cause, imaging of the neck and chest is typically part of the work-up.

04Dx

Diagnosis

• History and voice assessment, including swallowing symptoms.
• Laryngoscopy with a flexible camera, which shows whether the cords move and whether they close.
• Stroboscopy to check vibration, and sometimes laryngeal electromyography (EMG) to assess nerve function and prognosis.
• Swallowing assessment (videofluoroscopy or fibreoptic evaluation) when there is aspiration.
• CT or MRI of the neck and chest to look for a cause, and blood tests if indicated.
• Thyroid ultrasound and other tests depending on the findings.

05Voice

Voice and swallowing therapy

A speech-language pathologist teaches exercises, breathing and voice techniques to improve cord closure, use of voice and safe swallowing strategies such as chin tuck and thickened fluids if needed. Therapy is often the first step and continues alongside other treatments. See vocal exercises for singers and vocal warm-ups.

06Procedures

Medical and surgical treatment

• Observation: many cases improve in 6–12 months, so permanent surgery is often delayed.
• Injection laryngoplasty: a filler (such as hyaluronic acid, calcium hydroxylapatite or fat) is injected into the paralysed cord to bulk it up so the other cord can close against it; temporary or longer-lasting.
• Medialisation thyroplasty: a permanent implant moves the cord toward the middle.
• Arytenoid adduction in some cases.
• Nerve reinnervation procedures to restore tone.
• For bilateral paralysis: tracheostomy or procedures to widen the airway.
• Treatment of the underlying cause, such as a tumour.
• Procedures are chosen by a voice specialist according to symptoms and prognosis.

07Outlook

Outlook and recovery

Many people recover some or all function, especially when the nerve was stretched or irritated rather than cut. Recovery may take up to 12 months. Where recovery is incomplete, treatments can achieve a functional voice and safe swallowing. Voice therapy and good vocal hygiene help. Regular follow-up with an ENT specialist and speech therapist is advised.

09Cases

Three common situations

A person with a breathy voice and choking on water after thyroid surgery: prompt ENT evaluation and therapy; injection may help.

A person with sudden weak voice after a viral illness: laryngoscopy, voice therapy and watchful waiting for recovery.

A smoker with hoarseness and a persistent cough: needs a laryngoscopy and chest imaging.

10Living

Living with vocal cord paralysis: everyday tips

• Speak in short phrases and take a breath between them; avoid trying to talk over noise.
• Use a microphone, amplifier or a quiet environment when you have to speak for long.
• Stay hydrated and avoid clearing your throat forcefully.
• Take small sips and bites, sit upright when eating and follow swallowing advice from your therapist.
• Avoid lying down straight after meals, and treat reflux, which can aggravate symptoms.
• Tell people why your voice is weak to reduce the pressure to strain it.
• Report any new choking, fever or cough after eating, which can signal aspiration.

11Children

Vocal cord paralysis in babies and children

In infants, vocal cord paralysis may be present from birth or follow heart surgery or birth trauma, and shows up as a weak or absent cry, noisy breathing, feeding difficulty with choking or coughing, and sometimes blue spells. Evaluation by a paediatric ENT, with a flexible laryngoscopy and swallowing assessment, is urgent. Many babies with unilateral paralysis recover over months, and feeding is managed with thickened feeds and speech-language therapy. Bilateral paralysis may need airway intervention.

12Summary

Key points to remember

Vocal cord paralysis causes a breathy voice and swallowing problems, and is diagnosed by looking at the cords with a camera. Many cases recover; therapy, injections and surgery help when they do not. Seek assessment for voice change after surgery or any swallowing or breathing difficulty. Our ENT team can examine your voice and airway.

This guide is for general information and does not replace an examination by your own doctor or ENT specialist.