Description

• A painful disorder of the sensory nucleus of the 5th cranial (trigeminal) nerve that produces episodic, paroxysmal, severe, lancinating facial pain lasting seconds to minutes
• Often precipitated by stimulation of well-defined, ipsilateral trigger zones: usually perioral, perinasal, and occasionally intraoral (e.g., by talking, washing your face, shaving, or exposure to cold air)
• Subtypes:
  • Classical: secondary to neurovascular compression
  • Idiopathic: no abnormalities seen on neuroimaging
  • Secondary: cerebellopontine angle tumors (e.g., meningioma); tumors of cranial nerve (CN) V (e.g., neuroma, vascular malformations), trauma, demyelinating disease (e.g., multiple sclerosis [MS])
• System(s) affected: nervous
• Synonym(s): tic douloureux; Fothergill neuralgia; trifacial neuralgia; prosopalgia

Epidemiology

Incidence

• 4 to 13 per 100,000 per year
  • Women: 5.9/100,000 per year
  • Men: 3.4/100,000 per year
  • >70 years of age: ~25.6/100,000 per year
• Predominant age:
  • >50 years
  • Rare: <35 years of age (consider another primary disease, such as MS); see “Etiology and Pathophysiology.”
• Predominant sex: female (~2:1)

Prevalence
16/100,000 with lifetime prevalence of 0.16–0.3%

Pediatric Considerations
Unusual during childhood

Pregnancy Considerations
Teratogenicity of medication therapy limits their use during 1st and 2nd trimesters

Etiology and Pathophysiology

• Compression of the trigeminal nerve root by an anomalous artery or vein usually within a few millimeters of entry of the nerve into the pons (accounts for up to 90% cases)
• Compression of trigeminal nerve by tumors such as meningioma, acoustic neuroma, or arteriovenous malformation
• 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 such as hyperexcitability of damaged nerves and transmission of action potentials along adjacent, undamaged, and unstimulated sensory fibers.

Genetics
None confirmed, possible mutations in voltage-gated sodium channels

Risk Factors

Unknown

Commonly Associated Conditions

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