TRIGEMINAL NEURALGIA


I. Clinical Features and epidemiology
  1. Recurring, brief episodes of facial pain with sudden onset
  2. Occurs in distribution of one or more branches of the trigeminal nerve (maxillary is most common; ophthalmic is least common)
  3. Almost always unilateral
  4. Typically severe in intensity, stabbing in character; Little variation from one episode to another in a given patient
  5. Unlike migraine, episodes are brief and not accompanied by aura, nausea, or photophobia
  6. Often triggered by movement of the face (from talking, chewing, etc.)
  7. Peak incidence is at 60-70yo
  8. Occurs in 1-2% of pts with multiple sclerosis, with younger onset than other cases
  9. Etiology unclear; may involve demyelination
II. Classified into "classical" or "symptomatic"
  1. Classical = idiopathic
  2. Symptomatic = identified etiology is present, e.g. compression of trigeminal nerve from a vascular lesion
III. Management
  1. Consider MRI/MRA of brain if multiple sclerosis is suspected, sx are bilateral, pt is young, sx are refractory to therapy, or other cranial nerve abnormalities are present
  2. Electromyography for abnormal trigeminal reflexes has sensitivity of 87% and specificity of 94% in identifying a secondary cause for trigeminal neuralgia
  3. Carbamazepine 200-1,200 mg/d (divided BID-TID) has been shown effective in placebo-controlled studies
  4. Other medication options (less evidence) include: oxcarbazepine, baclofen, lamotrigine, and pimozide
  5. Surgical therapy: gamma knife, balloon decompression, glycerol injection, microvascular decompression, partial trigeminal rhizotomy
(Sources include Core Content Review of Family Medicine, 2012)