Trigeminal Neuralgia

Description

• A painful disorder of the sensory nucleus of the trigeminal nerve (cranial nerve [CN] V) that produces episodic, paroxysmal, severe, lancinating facial pain lasting seconds to minutes in the distribution of ≥1 divisions of the nerve
• Often precipitated by stimulation of well-defined, ipsilateral trigger zones: usually perioral, perinasal, and, occasionally, intraoral (e.g., by washing, shaving)
• System(s) affected: nervous
• Synonym(s): tic douloureux, Fothergill neuralgia, trifacial neuralgia, prosopalgia

Epidemiology

• Women: 5.9/100,000/year
• Men: 3.4/100,000/year
• >70 years of age: ~25.6/100,000/year
• Predominant age:
  • >50 years; incidence increases with age.
  • Rare: <35 years of age (consider another primary disease; see “Etiology and Pathophysiology”)
• Predominant sex: female > male (~2:1)

Prevalence
16/100,000

Pediatric Considerations
Unusual during childhood

Pregnancy Considerations
Teratogenicity limits therapy for 1st and 2nd trimesters.

Etiology and Pathophysiology

• Demyelination around the compression site seems to be the mechanism by which compression of nerves leads to symptoms.
• Demyelinated lesions may set up an ectopic impulse generation causing erratic responses: hyperexcitability of damaged nerves and transmission of action potentials along adjacent, undamaged, unstimulated sensory fibers
• Compression of trigeminal nerve by anomalous arteries or veins of posterior fossa, compressing trigeminal root
• Etiologic classification:
  • Idiopathic (classic)
  • Secondary: cerebellopontine angle tumors (e.g., meningioma); tumors of CN V (e.g., neuroma, vascular malformations), trauma, demyelinating disease (e.g., multiple sclerosis [MS])

Risk Factors

Unknown

Commonly Associated Conditions

• Sjögren syndrome; rheumatoid arthritis
• Chronic meningitis
• Acute polyneuropathy
• MS
• Hemifacial spasm
• Charcot-Marie-Tooth neuropathy
• Glossopharyngeal neuralgia