Skip to content

Trigeminal Neuralgia

Summary

fleuron

  • Chronic neuropathic pain disorder affecting the trigeminal nerve
  • Characterised by sudden, severe, electric shock-like pain in the face
  • Diagnosis primarily clinical, with MRI to rule out secondary causes1

Pathophysiology

  • Neurovascular compression of the trigeminal nerve root entry zone, most commonly by superior cerebellar artery
  • Demyelination of trigeminal sensory fibres leading to ephaptic transmission
  • Central sensitization and hyperexcitability of trigeminal nuclei

Demographics

  • Incidence: 4-13 per 100,000 person-years
  • Peak onset: 50-60 years of age
  • Female to male ratio: 1.5-2:1
  • Higher prevalence in patients with multiple sclerosis (1-6.3%)

Diagnosis

  • Based on clinical presentation and patient history
  • International Headache Society diagnostic criteria:
    • At least three attacks of unilateral facial pain
    • Occurring in one or more divisions of the trigeminal nerve
    • Pain has at least three of the following characteristics:
    • Recurring in paroxysmal attacks
    • Severe intensity
    • Electric shock-like, shooting, stabbing, or sharp in quality
    • Lasting from a fraction of a second to 2 minutes
    • Triggered by innocuous stimuli
  • No clinically evident neurological deficit

Imaging

  • MRI brain with contrast:
    • To exclude secondary causes (e.g., tumours, multiple sclerosis)
    • High-resolution T2-weighted sequences to visualise neurovascular compression
  • MR angiography:
    • To evaluate vascular anatomy and identify compressing vessels
  • DTI and tractography:
    • To assess microstructural changes in trigeminal nerve

panels-1

  • 50-year-old patient with multiple sclerosis presented with a 6 month history of right sided trigeminal neuralgia.
  • A T2-hyperintense demyelinating lesion in the right hemipons corresponds to intraparenchymal fascicles of the trigeminal nerve.

Treatment

  • Carbamazepine first-line; microvascular decompression for refractory cases with a compressing vessel
  • MRI is done to identify neurovascular compression at the root entry zone and to exclude a secondary cause (tumour or MS plaque)

  1. Bendtsen et al. Advances in diagnosis, classification, pathophysiology, and management of trigeminal neuralgia. 2020. The Lancet. Neurology - Open in new tab. ↩