What are the other Names for this Condition? (Also known as/Synonyms)

• ITN (Idiopathic Trigeminal Neuralgia)

What is Idiopathic Trigeminal Neuralgia? (Definition/Background Information)

• Trigeminal neuralgia is chronic facial pain due to involvement of the trigeminal nerve. It can cause brief and recurrent episodes of severe to excruciating pain. The condition is generally observed in middle-aged and older adults and may occur secondary to any lesion, disease, or other factors
• When the cause of trigeminal neuralgia remains unidentified, but neurovascular compression of the trigeminal nerve root is observed; and, on imaging and electrophysiological studies, no anatomical changes and atrophic defects are noted, then it is termed Idiopathic Trigeminal Neuralgia (ITN). It is classified into the following subtypes:
  • Idiopathic Trigeminal Neuralgia, purely Paroxysmal - here, in between two pain episodes, most individuals present no pain and remain asymptomatic
  • Idiopathic Trigeminal Neuralgia with Concomitant Continuous Pain - here, prolonged or persistent background pain may be observed in the affected region (between two pain episodes)

The criteria for diagnosis of Trigeminal Neuralgia as outlined by the International Headache Society (IHS) is given below:

• Neither classical trigeminal neuralgia nor secondary trigeminal neuralgia has been confirmed by adequate investigation including electrophysiological tests and MRI
• Recurrent paroxysms of unilateral facial pain (either purely paroxysmal or associated with concomitant continuous or near-continuous pain) in the distribution of one or more divisions of the trigeminal nerve, and fulfilling the criterion below:
• Pain has all of the following characteristics:
  • Lasting from a fraction of a second to 2 minutes; although, in a few patients, the attacks may last for more than 2 minutes
  • Severe intensity (pain can become more severe over time)
  • Electric shock-like, shooting, stabbing or sharp in quality
• Precipitated by innocuous stimuli within the affected trigeminal distribution (the physician must endeavor to confirm the same)
• Not better accounted for by another ICHD-3 diagnosis

(Source: International Headache Society Classification ICHD-3, London, United Kingdom)