Vocal Cord Paralysis

Vocal cord (vocal fold) paralysis is caused by recurrent laryngeal nerve (RLN) or vagus nerve injury that leaves one or both vocal folds in a paramedian or lateral position. Common etiologies include thyroid surgery, anterior cervical spine surgery, lung apex tumors (Pancoast), aortic surgery, mediastinal malignancy, neck trauma, viral neuropathy, and idiopathic causes (up to 20%).

Unilateral paralysis presents with breathy dysphonia, vocal fatigue, weak cough, and aspiration of liquids. Bilateral paralysis typically produces severe inspiratory stridor and dyspnea while voice is relatively preserved; it is an airway emergency. Diagnosis combines flexible laryngoscopy, laryngeal electromyography (LEMG) for prognosis, stroboscopy, and CT skull base to mediastinum to identify a structural cause along the entire vagus/RLN course.

Treatment depends on laterality, etiology, and time since injury. Voice therapy is first-line for unilateral cases with hope of recovery within 6-12 months. Temporary injection laryngoplasty (hyaluronic acid, carboxymethylcellulose) restores closure early. Permanent options include type I medialization thyroplasty with Silastic or Gore-Tex, arytenoid adduction, and laryngeal reinnervation (ansa cervicalis-RLN). Bilateral paralysis may require tracheostomy, posterior cordotomy, partial arytenoidectomy, or selective reinnervation.