Long-term pain disorder that affects the trigeminal nerve

Aetiology

• More common in elderly (>60 years) women
• Attacks may be brought on by stimulation of one or more trigger zones in the face
  • Washing, shaving, a cold wind and chewing are examples of trivial stimuli that provoke pain

Pathophysiology

• Cause is unclear but it is thought to be caused by compression of the nerve

Clinical features

• Severe stabbing unilateral stabbing facial pain - occurs in the distribution of CN V
• Attacks last 1-90 secs
• Episodes occur many times a day with a refractory period after each
• Bouts of pain may last weeks-months
• Spontaneous remissions last months or years before (almost invariable) recurrence

Investigations

• MRI brain

Management

Medical

• Carbamazepine first line, gabapentin, phenytoin

Surgical

• Ablation, decompression