Bulbar Palsy

Bulbar palsy refers to a range of different signs and symptoms linked to impairment of function of the cranial nerves IX, X, XI, XII, which occurs due to a lower motor neuron lesion in the medulla oblongata or from lesions of the lower cranial nerves outside the brainstem.

Signs and symptoms

Symptoms

  • dysphagia (difficulty in swallowing)
  • difficulty in chewing
  • nasal regurgitation
  • slurring of speech
  • difficulty in handling secretions
  • aspiration of liquids
  • dysphonia (defective use of the voice, inability to produce sound due to laryngeal weakness)
  • dysarthria (difficulty in articulating words due to a CNS problem)

Signs

  • nasal speech lacking in modulation and difficulty with all consonants
  • tongue is atrophic and shows fasciculations.
  • dribbling of saliva.
  • weakness of the soft palate, examined by asking the patient to say aah.
  • normal or absent jaw jerk
  • absent gag reflex

In addition, there may be lower motor neuron lesions of the limbs.

The ocular muscles are spared and this differentiates it from myasthenia gravis.

Causes

  • Genetic: Kennedy's disease, acute intermittent porphyria
  • Vascular causes: medullary infarction, such as lateral or medial medullary infarction.
  • Degenerative diseases: amyotrophic lateral sclerosis, syringobulbia, Wolfram syndrome
  • Inflammatory/infective: Guillain–Barré syndrome, poliomyelitis, Lyme disease
  • Malignancy: brain-stem glioma, malignant meningitis
  • Toxic: botulism, venom of bark scorpion (species Centruroides), some neurotoxic snake venoms
  • Autoimmune: myasthenia gravis

Diagnosis

Differential diagnosis

In contrast, pseudobulbar palsy is a clinical syndrome similar to bulbar palsy but in which the damage is located in upper motor neurons of the corticobulbar tracts in the mid-pons (i.e., in the cranial nerves IX-XII), that is the nerve cells coming down from the cerebral cortex innervating the motor nuclei in the medulla. This is usually caused by stroke.

Treatment

Depends on diagnosis

See also

  • Progressive bulbar palsy