Paralysis and paresis of the vocal folds, or vocal cords, result from abnormal nerve input to the voice box muscles, also called the laryngeal muscles. Paralysis refers to a total interruption of nerve impulses, which results in no muscle movement. Paresis refers to a partial interruption of nerve impulse, and this results in weak or abnormal movement. When you experience vocal fold paralysis or paresis, you are unable to produce vocalizations as you normally would—if at all.
Vocal fold paralysis and paresis can happen to anyone, regardless of age or gender.
The Nerves That Control Your Voice
Vocal fold movements are the result of a coordinated contraction of multiple muscles which are controlled by two nerves. The nerves that receive these signals are the:
- Superior laryngeal nerve (SLN), which carries signals to the cricothyroid muscle, located between the cricoid and thyroid cartilages. Because the cricothyroid muscle adjusts the tension of the vocal fold for high notes during singing, SLN paralysis and paresis result in abnormalities in voice pitch and the inability to sing with smooth change to a higher note. Some patients with SLN paralysis or paresis have a normal speaking voice but an abnormal singing voice.
- The recurrent laryngeal nerve (RLN), which carries signals to different voice box muscles responsible for opening or closing vocal folds. The vocal folds normally open for breathing or coughing and close during voice use and swallowing. The RLN is at greater risk for injury because of its length and its position in the body. Damage may occur to the RLN due to infection; tumors of the brain, neck, chest or voice box; or complications during surgical procedures in the head, neck or chest. Most cases of vocal fold paralysis or paresis occur due to damage to the RLN.
Why You May Suddenly Be Unable to Speak
Chance of recovery from vocal fold paralysis or paresis depends on the underlying cause. Vocal fold paralysis or paresis may be temporary or permanent, and there are a variety of available treatment options. If the cause of your vocal fold paralysis or paresis is believed to be reversible, your doctor will likely not recommend surgical treatment.
Your doctor may not be able to detect the exact cause of your vocal fold paralysis or paresis—this is the case in about half of all patients. When the cause cannot be determined, it is referred to as idiopathic. Although the exact cause may not be able to be determined, there are a few common causes of vocal fold paralysis or paresis. These possible causes include:
- Injury during surgery, including surgery in the thyroid gland, carotid artery, lungs, esophagus or heart
- Complications during an endotracheal intubation
- Blunt trauma to the neck or chest
- Tumors in the head, neck or chest
- Viral infection
Signs You May Have Vocal Fold Paralysis or Paresis
- Hoarseness, characterized by a rough or croaky voice
- Breathy voice
- Difficulty vocalizing
- Gargling sound when you speak, also known as diplophonia
- Shortness of breath
- Noisy breathing, also referred to as stridor
- Weak or ineffective cough
- Choking or coughing when swallowing
- Commonly getting food stuck in your throat
How Your Condition May Be Diagnosed
If you believe you may be experiencing symptoms of vocal fold paralysis or paresis, it is recommended that you see an ear, nose and throat specialist, sometimes referred to as an otolaryngologist. Diagnoses will begin with a general examination. Then, your doctor will ask about your symptoms and any factors that may affect your condition, such as voice use or tobacco use.
Next, your ENT specialist will examine your voice box. The goal is to determine whether one or both vocal folds may be affected.
Once your doctor has a decent understanding of your current vocal condition, you may undergo a test known as a laryngeal electromyography (LEMG), as well as some combination of blood tests, x-rays, CT scans, or MRIs.
A laryngeal electromyography (LEMG) is a physical exam that tests the nerve signals in the muscles in the larynx as they contract. Small needles are used to measure the electrical currents in the muscles. These electric currents can indicate whether there is a disruption with the nerve inputs and to what extent.
Treating Vocal Fold Paralysis and Paresis
There are two treatment strategies commonly recommended for vocal cord paralysis and paresis.
The two most common treatment options for voice paralysis and paresis are:
- Voice therapy — Voice therapy is a form of physical therapy that targets the muscles involved in voice paralysis or paresis.
- Phonosurgery — Phonosurgery is an operation that improves voice function by repositioning or reshaping the vocal folds.
Your doctor will likely first recommend the less invasive of the two. For patients who do not respond to therapy, surgery may be recommended.
If you have noticed change in your voice quality,contact an otolaryngologist, or ear, nose and throat specialist. Call us today at 404.257.1589 (Atlanta) or 770.777.1100 (Alpharetta), or book an appointment with us online now to discuss your voice concerns.
