Vocal Fold Paralysis
Vocal Fold Paralysis results in the inability of the vocal fold to move. It is caused by damage to the nerve that innervates the vocal fold (recurrent laryngeal nerve). The recurrent laryngeal nerve travels from the brain down the neck and into the chest before turning upwards back to the larynx. The nerve on the left side is longer than the right side, traveling further in to the chest, and is therefore, more prone to injury. Vocal Fold Paralysis is usually one sided (unilateral). However, on occasion, it can also be seen bilaterally.
There are numerous causes for Vocal Cord Paralysis. These include trauma (external injury, surgical injury or intubation injury), congestive heart failure, bacterial or viral infection, cancer, tumor compressing the nerve or neuromuscular problems. Occasionally, the cause of Vocal Cord Paralysis is unknown.
The most common symptom of Vocal Cord Paralysis is hoarseness. Vocal fatigue and aspiration (coughing when swallowing liquids due to penetration in to the windpipe (trachea)) are also commonly seen. Noisy breathing and breathing difficulties are seen with bilateral paralysis. The symptoms vary depending on how severely the patient is affected and how well they are able to compensate for the problem.
Treatment of Vocal Fold Paralysis depends on the cause and whether the paralysis is unilateral or bilateral. On occasion, the nerve does heal itself and regain function. It is therefore recommended to schedule any type of corrective surgery six months following the paralysis in order to give the vocal folds time to heal themselves.
Voice therapy and medications are not usually beneficial in reversing the paralysis. However, if the source of the nerve irritation and resultant paralysis is thought to be secondary to inflammation, steroids may be prescribed in order to reduce inflammation. Voice therapy helps to achieve a stronger voice by strengthening the other muscles in the larynx that are not paralyzed.
In most cases of unilateral Vocal Fold Paralysis, the voice can be restored to a near-normal conversational voice. Treatment is aimed at repositioning the immobile vocal fold closer to the midline (vocal fold medialization). This is accomplished by injecting the vocal fold with a filling agent (such as collagen) or by placing a block of artificial material into the larynx, adjacent to the paralyzed vocal fold, via an external approach through the neck (medialization laryngoplasty).
If bilateral vocal fold paralysis restricts breathing ability, a tracheotomy may be necessary to help accommodate breathing.