Trigeminal Neuralgia

1. B. Wayne Blount, MD, MPH Trigeminal Neuralgia

2. “Tic Doloureau” • 4.3 per 100,000 • Slight female predominance : 1.74 t0 1 • Peak incidence 60-70 y.o. • Unusual before age 40 • No racial prediliction

3. “Tic Doloureau” • Higher incidence with M.S. & HTN • Spontaneous remission possible, BUT unusual • Most patients will have episodic attacks over many years

4. Now 2 Types Are Identified • Classical • Symptomatic

5. Classical Criteria • A. Paroxysmal attacks of pain lasting from a fraction of a second to 2 minutes, affecting 1 or more divisions of the trigeminal nerve, & fulfilling criteria B & C. • B. Pain has at least 1 of the following characteristics: • 1. Intense, sharp, superficial, or stabbing • Precipitated from trigger zones or by trigger factors

6. Classical Criteria • C. Attacks are stereotyped in the individual patient • D. No clinically evident neuro deficit • E. Not attributed to another disorder.

7. Symptomatic Criteria • A. Paroxysmal attacks of pain lasting from a fraction of a second to 2 minutes, with or w/o persistence of pain between paroxysms, affecting 1 or more divisions of the trigeminal nerve, & fulfilling criteria B & C. • B. . Pain has at least 1 of the following characteristics: • 1. Intense, sharp, superficial, or stabbing • Precipitated from trigger zones or by trigger factors

8. Symptomatic Criteria • C. Attacks are stereotyped in the individual patient • D. A causative lesion, other than vascular compression, has been demonstrated by special investigations &/or posterior fossa exploration.

9. Pathophysiology

10. ? Pathophysiology ? • Demyelination of the trigeminal nerve, causing ectopic impulses and then ephaptic conduction • Vascular compression of the nerve root by aberrant or tortuous vessels • Compression by tumor • Amyloid • A-V malformation • Pons Infarct • Bony compression

11. Diagnosis • Clinical • Consider in all patients with unilateral facial pain • Prompt Dx important as pain can be severe • Distinguish classical from symptomatic for RX purposes • Look for “red flags” of other diseases

12. Red Flags • Abnormal Neuro exam • Abnormal oral, dental, or ear exam • Age < 40 yrs • Bilateral SXs • Dizziness or vertigo

13. Red Flags • Hearing loss • Numbness • Pain lasting > 2 minutes • Pain outside of trigeminal distribution • Visual changes

14. Diagnostic History • Very important • Recurrent, unilateral facial pain • Lasts seconds • May recur 100’s of times per day • Pain : • Severe Stereotypical • Sharp Stabbing • Superficial Shock-like

15. Diagnostic History • 1 or more of the nerve’s divisions • Trigger factors: • Talking Shaving • Smiling Applying make-up • Chewing Wind • Teeth brushing • Age > 40 yrs. • Ask about other neuroSx • Asymptomatic time or not ?

16. Physical Exam • Usually a normal exam • Useful for identifying abnormals that point to other DXs • HEENT, including TMJ & Masseter • Oral exam, including teeth & gums • Neuro exam • Check for trigger zones

17. Diagnostic Testing • Generally Not helpful • MRI is the Test of Choice : ‘C’ Rec • ? Trigeminal reflex testing? Unclear usefulness & I would NOT do it

18. Differential List • Cluster HA Dental Pain • Giant Cell Arteritis Migraine • Glossopharyngeal • Neuralgia Otitis Media • Intracranial Tumor Sinusitis • Multiple Sclerosis TMJ Syndrome • Postherpetic Neuralgia Paroxysmal Hemicrania

19. Treatment • Medical • Surgical • No Behavioral, unless it becomes a cause of Chronic Pain

20. Medical Treatment • Carbamazepine : ‘A’ Rec • NNT = 2.5 (For trigeminal Neuralgia) • NNH = 3.7 (For all diseases) • Some suggest it as a diagnostic trial • Doses range from 100 to 2,400 mg per day • Most respond to 200 to 800 mg per day • Immediate release (lasts about 6 hrs.) • Extended release (lasts about 12 hrs.)

21. Medical Treatment • Carbamazepine Should be the initial Rx of choice for classical Trigeminal Neuralgia • If get no or only partial response to carbamazepine, add or substitute another pharmacologic agent:

22. Medical Treatment • Other agents to try : ( Not listed in any order) • Baclofen : 10 m- 80 mg daily • Dilantin • Lamictal • Neurontin • Topamax • Klonopin • Orap • Depakene

23. Medical Treatment • A recent Cochrane review said there was insufficient evidence to show benefit from non-epileptic agents in trigeminal neuralgia

24. Follow-up • Achieve balance between pain and med side effects • Most want complete remission, which is possible and warranted • Can try a trial sans meds after “several” months symptom free (Think 4-6)

25. Surgical Treatment • After failure of Pharm agents • Unusual • Recurrences occur for many • Both percutaneous & open techniques • Glycerol injection Ballon Compression • Radio Rhizotomy Gamma knife • Partial Rhizotomy Microvascular decompression

26. Summary • 2 Types of trigeminal neuralgia • A clinical DX • Everyone gets a head & face MRI • Carbamazepine is the treatment of choice.

27. References • Kraft, RM. Trigeminal Neuralgia. AFP. 2008;77:1291-1296. • Cochrane Collaboration • Haanpaa M, et al. Neuropathic Facial Pain. Suppl Clin Neurophysiol. 2006;58:153-170.

28. References • Cruccu G, et al. Diagnosis of trigeminal neuralgia. In: Cruccu G, et al. Brainstem Function & Dysfunction. Amsterdam: Elsevier; 2006:171-186. • Wayne Blount