Laryngeal Vocal Cord Palsy
Motor Paralysis:
1) Cortical paralysis: These lesions are rare as the larynx has bilateral motor innervation. May be seen in case of :
- Congenital cerebral palsy
- Encephalitis
- Kernicterus
- Diffuse cerebral arteriosclerosis
2) Corticobulbar paralysis: These are extremely rare due to paralysis of the corticobulbar tracts.
3) Bulbar paralysis: This is a flaccid type of paralysis due to destruction of all or part of nucleus ambiguous in the medulla.
- Vascular insufficiencies such as vertebral or postero-inferior cerebellar arteries
- Multiple sclerosis
- Intramedullary tumours like gliomas.
4) Peripheral causes: They are responsible for 90 percent of the vocal cord paralysis. The lesion involves the fibres of the laryngeal nerves from the surface of the medulla upto the larynx. Usually combines with multiple cranial nerves.
Peripheral paralysis of the vocal cords is divided into two groups:
- High vagal paralysis: Lesions near the ganglion with only recurrent laryngeal nerve damage
- Low vagal paralysis: Nerve intact upto ganglion
Peripheral causes of vocal cord palsy:
Inflammatory
- Neuritis
- Meningitis
- Diphtheria
- Herpes zoster
- Tuberculosis
- Jugular bulb thrombophlebitis.
Neoplastic
- Meningoma
- Glomus jugulare
- Thyroid Malignancy
- Thymus tumours.
- Malignant lymphoma
Trauma
- Blunt neck trauma
- Bullet wounds
- Fracture clavicle
- Surgical trauma
- Thyroidectomy
- Tracheostomy
- Radical neck dissection
- Pneumonectomy
