Respiratory · Year 1 · from Respiratory
Case 3: Recurrent Laryngeal Nerve Palsy
Clinical Image
Source: Wikimedia Commons - Vocal Cord Paralysis - Public Domain
Case Presentation
A 58-year-old man with a history of smoking (40 pack-years) presents with progressive hoarseness over the past 3 months. He also reports a 15-pound unintentional weight loss, chronic cough, and mild dysphagia. On examination, he appears cachectic. Vital signs are stable. Indirect laryngoscopy reveals left vocal cord paralysis with the cord fixed in the paramedian position. The right vocal cord moves normally. Given his risk factors and presentation, CT chest is performed, revealing a large left hilar mass with mediastinal lymphadenopathy. Subsequent biopsy confirms non-small cell lung cancer (squamous cell carcinoma). The hoarseness is attributed to compression or invasion of the left recurrent laryngeal nerve by the tumor. The left recurrent laryngeal nerve is particularly vulnerable because of its long course: it branches from the vagus nerve in the thorax, loops under the aortic arch, and ascends in the tracheoesophageal groove to reach the larynx. This anatomical pathway makes it susceptible to compression by aortic aneurysms, mediastinal tumors, and thoracic surgical procedures. The patient is referred to oncology for staging and treatment planning.
Key Learning Points
- The left recurrent laryngeal nerve loops under the aortic arch, making it vulnerable to compression by mediastinal tumors, aortic aneurysms, and thoracic surgery
- The recurrent laryngeal nerve innervates all intrinsic laryngeal muscles except the cricothyroid (which is innervated by the external branch of the superior laryngeal nerve)
- Unilateral vocal cord paralysis causes hoarseness; bilateral paralysis can cause airway obstruction
- New hoarseness in a smoker should prompt evaluation for lung cancer, particularly left-sided tumors that may compress the left recurrent laryngeal nerve