47. Causes, symptoms and investigation of vocal cord paralysis. Laterofixation.

what are the causes of vocal fold paralysis

• Due to superior and/or recurrent laryngeal nerve injury

• A sign of a disease – not a diagnosis by itself

What are the types of lesions that cause vocal fold paralysis

central lesions

peripheral lesions

what are the causes of central lesions

• cerebrovascular accident

• head injury

• MS

• ALS

• skull base tumours

What are the causes of peripheral lesions

•   Tumor (primary or metastatic): lung, bronchi, esophagus, trachea, thyroid

• Iatrogenic injury: thyroid and parathyroid surgery (recurrent laryngeal nerve)

• Neuritis: VZV, HSV, EBV, Lyme disease

• Systemic disease: SLE, amyloidosis, sarcoidosis

  • TB → scarring of mediastinum

What are the clinical signs of unilateral VFP

• breathy

• hoarse

• weak voice with decreased pitch + volume

what are the clinical signs of bilateral VFP

• voice often sounds normal + severe respiratory distress

• (inspiratory stridor, dyspnea, cough)

How do you diagnose VFP

• History

• Laryngoscopy:

  • Unilateral: median or paramedian position of vocal cords

  • Bilateral: intermediate position of the vocal cords

• Stroboscopy, electromyography of larynx muscles

• Imaging (CXR, CT, MRI, US)

what is the treatment of unilateral VFP

• voice therapy + electrical stimulation to prevent muscular atrophy

• if no improvement → phonosurgery

  • medialisation of affected cord

what is the treatment of bilateral VFP

• electrical stimulation to prevent muscular atrophy

• if no respuratory distress

  • monitor + wait for improvement

• if respiratory distress

  • intubation, tracheotomy, lateralisation of affected cord

what is laterofixation/ lateralisation

• widening operation where teh vocal cords are moved and fixed in a lateral position

• usually performed in bilateral vocal fold paralysis to improve breathing

What are the procedures of lateralization

• Thyroplasty type 2

  • (lateralization of the vocal folds)

• Arytenoidectomy

  • (removal of the arytenoid cartilage à laryngeal inlet widened)

• Cordectomy

  • (part or all of vocal cords are removed)

• Nerve muscle implant

  • (sternohyoid muscle with its nerve supply is transplanted into the paralyzed posterior cricoarytenoid)