Vocal Fold Paralysis

Key Features

• Can result from a lesion or damage to either the vagus or recurrent laryngeal nerve

• Usually results in breathy dysphonia and effortful voicing

Clinical Findings

• Common causes of unilateral recurrent laryngeal nerve involvement

  • Thyroid surgery (and occasionally thyroid cancer)

  • Other neck surgery (anterior discectomy and carotid endarterectomy)

  • Mediastinal or apical involvement by lung cancer

• Causes of bilateral fold paralysis

  • Thyroid surgery

  • Esophageal cancer

  • Ventricular shunt malfunction

• Bilateral fold paralysis

  • Usually causes inspiratory stridor with deep inspiration

  • If onset is insidious, it may be asymptomatic at rest and the patient may have a normal voice

• Unilateral or bilateral fold immobility may also be seen in

  • Cricoarytenoid arthritis secondary to advanced rheumatoid arthritis

  • Intubation injuries

  • Glottic and subglottic stenosis

  • Laryngeal cancer

• Skull base tumors often involve or abut upon lower cranial nerves and may affect the vagus nerve directly, or the vagus nerve may be damaged during surgical management of the lesion

• While iatrogenic injury is the most common cause of unilateral vocal fold paralysis, the second most common cause is idiopathic

• However, before deciding whether the paralysis is due to iatrogenic injury or is idiopathic, the clinician must exclude other causes, such as malignancy

Diagnosis

• In the absence of other cranial neuropathies, a CT scan with contrast from the skull base to the aorto-pulmonary window (the span of the recurrent laryngeal nerve) should be performed

• If other cranial nerve deficits or high vagal weakness with palate paralysis is noted, an MRI scan of the brain and brainstem is warranted

Treatment

• The goal of intervention is the creation of a safe airway with minimal reduction in voice quality and airway protection from aspiration

• A number of fold lateralization procedures for bilateral paralysis have been advocated as a means of removing the tracheotomy tube

• Surgical management of persistent or irrecoverable symptomatic unilateral vocal fold paralysis

  • Primary goal is medialization of the paralyzed fold in order to create a stable platform for vocal fold vibration

  • Additional goals include advancing diet and improving pulmonary toilet by facilitating cough

  • Success has been reported for years with injection laryngoplasty using Teflon, Gelfoam, fat and collagen

  • Teflon is the only permanent injectable material, but its use is discouraged because of granuloma formation within the vocal folds of some patients

  • Temporary injectable materials, such as collagen or fat, provide excellent temporary restoration of voice and can be placed under local or general anesthesia

• Once the paralysis is determined to be permanent, formal medialization thyroplasty may be performed

  • A small window in the thyroid cartilage is created and an implant is placed between the thyroarytenoid muscle and inner table of the thyroid cartilage

  • This procedure moves the vocal fold medially and creates a stable platform for bilateral, symmetric mucosal vibration