What is vocal fold paralysis?

The vocal folds of the larynx which is a major source of sound in speech, is controlled by the vagus nerve, the 10th of the 12 cranial nerves. By the recurrent laryngeal nerve and the superior laryngeal nerve inside the vagus nerve, the muscles inside the larynx and the vocal folds move together naturally to cause sounds and breathing, and to prevent food from going down through the trachea.

The vocal folds are brought together by the action of laryngeal nerves, so that air pressure builds up beneath the larynx, generating sound through the rhythmic opening and closing of the vocal folds. However, when the nerves are paralyzed, the vocal folds do not open or close properly and remain open, leaving the airway passage and the lungs unprotected. It causes hoarseness and coughing because the food goes down and gets stuck in the trachea.

Vocal Fold Paralysis View (1)

Vocal Fold Paralysis View (2)

This condition is called vocal fold paralysis. When only one side is paralyzed, it is called unilateral vocal fold paralysis, and when both sides are paralyzed, it is called bilateral vocal fold paralysis.

However, it is very important to know that laryngeal nerve paralysis is not the only cause for abnormal movement of the vocal fold. There may be other reasons such as:

- A tumor inside the larynx
- Arytenoids dislocation from trauma
- Damage to the joints
- Congenital malformation
- Inflammation
- Infection of the larynx
- Scarred vocal fold

Therefore, it is important to find out the exact reason why this has occurred.

For this differential diagnosis, examinations such as computer filming, laryngoscope, and laryngeal stroboscopy are performed. The most important thing is to have Laryngeal Electromyography (LEMG) and find out the accurate reason. Yeson Voice Center has the High-tech Laryngeal Electromyography Equipment and laryngeal imaging equipment which have not been introduced even in university hospitals.