Vocal Cord Paralysis

Key Features

• Hoarseness or stridor

• May present with difficulty swallowing

• Unilateral or bilateral vocal cord paralysis

  • May be congenital

  • May result from injury to the recurrent laryngeal nerves (more common)

• Risk factors for acquired paralysis include

  • Difficult delivery (especially face presentation)

  • Neck and thoracic surgery (eg, ductal ligation or repair of tracheoesophageal fistula)

  • Trauma

  • Mediastinal masses

  • Central nervous system disease (eg, Arnold-Chiari malformation)

Clinical Findings

• Varying degrees of hoarseness, aspiration, or high-pitched stridor

• Unilateral cord paralysis

  • More likely to occur on the left because of the longer course of the left recurrent laryngeal nerve and its proximity to major thoracic structures

  • Patients are usually hoarse but rarely have stridor

• With bilateral cord paralysis,

  • The closer to midline the cords are positioned, the greater the airway obstruction

  • The more lateral the cords are positioned, the greater the tendency to aspirate and experience hoarseness or aphonia

• If partial function is preserved (paresis), the adductor muscles tend to operate better than the abductors, with a resultant high-pitched inspiratory stridor and normal voice

Diagnosis

• Paralysis can be assessed by

  • Direct visualization of vocal cord function with laryngoscopy

  • Recording the electrical activity of the muscles (electromyography), which can differentiate vocal fold paralysis from arytenoid dislocation

Treatment

• Airway intervention (tracheostomy) is rarely indicated in unilateral paralysis but is often necessary for bilateral paralysis