AUTHOR AND EDITOR INFORMATION

Section 1 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

INTRODUCTION

Section 2 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

Background

Trigeminal neuralgia (TN), also known as tic douloureux, is a pain syndrome recognizable by the patient's history alone. The condition is characterized by pain often accompanied by a brief facial spasm or tic. Pain distribution is unilateral and follows the sensory distribution of cranial nerve V, typically radiating to the maxillary (V2) or mandibular (V3) area. At times, both distributions are affected. Physical examination eliminates alternative diagnoses. Signs of cranial nerve dysfunction or other neurologic abnormality exclude the diagnosis of idiopathic TN and suggest that pain may be secondary to a structural lesion.

Pathophysiology

The mechanism of pain production remains controversial. One theory suggests that peripheral injury or disease of the trigeminal nerve increases afferent firing in the nerve; failure of central inhibitory mechanisms may be involved as well. Pain is perceived when nociceptive neurons in a trigeminal nucleus involve thalamic relay neurons.

Aneurysms, tumors, chronic meningeal inflammation, or other lesions may irritate trigeminal nerve roots along the pons. An abnormal vascular course of the superior cerebellar artery is often cited as the cause. In 90-95% of cases, no lesion is identified, and the etiology is labeled idiopathic by default. Uncommonly, an area of demyelination from multiple sclerosis may be the precipitant. Lesions of the entry zone of the trigeminal roots within the pons may cause a similar pain syndrome.

Infrequently, adjacent dental fillings composed of dissimilar metals may trigger attacks, and an atypical case has been reported following tongue piercing.

Frequency

International

TN is uncommon, with an estimated prevalence of 155 cases per million persons.

Mortality/Morbidity

• No mortality is associated with idiopathic TN, although secondary depression is common if a chronic pain syndrome evolves. In rare cases, pain may be so frequent that oral nutrition is impaired.
• In symptomatic or secondary TN, morbidity or mortality relates to the underlying cause of the pain syndrome.

Sex

The male-to-female ratio is 2:3.

Age

Development of trigeminal neuralgia in a young person suggests the possibility of multiple sclerosis.

• Idiopathic TN typically occurs in patients in the sixth decade of life, but it may occur at any age.
• Symptomatic or secondary TN tends to occur in younger patients.

CLINICAL

Section 3 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

History

History is the most important factor in the diagnosis of TN.

• Nature of pain
• • Pain is brief and paroxysmal, but it may occur in volleys of multiple attacks.
  • Pain is stabbing or shocklike and is typically severe.
• Distribution of pain
• • One or more branches of the trigeminal nerve (usually maxillary or mandibular) are involved.
  • Pain is unilateral (rarely bilateral).
• Duration of pain is typically from a few seconds to 1-2 minutes.
• Pain may occur several times a day; patients typically experience no pain between episodes.
• Trigger points
• • Various triggers may commonly precipitate a pain attack.
  • Light touch or vibration is the most provocative.
  • Activities such as shaving, face washing, or chewing often trigger an episode.
  • Stimuli as mild as a light breeze may provoke pain in some patients.
• Pain provokes brief muscle spasm of the facial muscles, thus producing the tic.

Physical

Physical examination findings are normal; in fact, a normal neurologic examination is part of the definition of idiopathic TN. Perform a careful examination of the cranial nerves, including the corneal reflex.

• Be alert to the presence of any abnormality on physical examination. Abnormality suggests that the pain syndrome is secondary to another process.
• Remember that patients report pain following stimulation of a trigger point; thus, some patients may limit their examination for fear of stimulating these points.

Causes

Most patients' conditions are idiopathic, but compression of the trigeminal roots by tumors or vascular anomalies may cause similar pain.

DIFFERENTIALS

Section 4 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

Other Problems to be Considered

Atypical facial pain
Glossopharyngeal neuralgia
Temporomandibular joint pain
Compression of trigeminal roots from tumors or aberrant vessels
Dental problems

WORKUP

Section 5 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

Imaging Studies

• Patients with characteristic history and normal neurologic examination may be treated without further workup. Some physicians recommend elective MRI for all patients to exclude an uncommon mass lesion or aberrant vessel compressing the nerve roots.
• Perform an MRI if atypical features are present.

TREATMENT

Section 6 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

Emergency Department Care

Care in the ED is generally limited to correct identification of TN, consideration of alternative diagnosis, pain relief, and coordination of follow-up care.

• Because of the time-limited character of pain with typical TN, patients often do not present to the ED for pain medication.
• In some patients, the typically episodic pain becomes constant or so frequent as to be debilitating.
• • Infusion of phenytoin is reportedly successful in interrupting such episodes, but the value of this therapy is anecdotal.
  • Coordinate therapy for refractory pain of TN with the primary care physician or consultants.

Consultations

Patients with a typical history and normal physical examination may be referred to their primary care physician for further care. Neurologic or neurosurgical consultations may be helpful, particularly if atypical features are present.

• Referral to a neurologist may be helpful if the diagnosis is in doubt.
• Referral to a neurosurgeon may be indicated for patients whose conditions prove refractory to medical treatment. Percutaneous radiofrequency ablation of a portion of the trigeminal ganglion is commonly performed, as are anesthetic blocks of the trigeminal ganglion. Less commonly performed is decompression of the region of trigeminal root entry of impinging vascular structures.
• Comprehensive pain center follow-up care may be helpful.

MEDICATION

Section 7 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

The goal of pharmacologic therapy is to reduce pain. Carbamazepine is regarded by most as the medical treatment of choice. Some advocate a trial of baclofen since it has fewer adverse effects.¹ The synergistic combination of carbamazepine and baclofen may provide relief from episodic pain.

Other anticonvulsants including phenytoin, oxcarbazepine, clonazepam, lamotrigine, valproic acid, and gabapentin are reportedly beneficial in some patients; however, controlled trials have not been performed. A small study reported topiramate beneficial in refractory cases; again, controlled trials are needed.²

Drug Category: Anticonvulsants

These agents may help control paroxysmal pain by limiting the aberrant transmission of nerve impulses.

Drug Category: Skeletal muscle relaxants

These agents are useful in the treatment of TN, although not FDA-approved for this indication. They have CNS depressant properties as indicated by the production of sedation with somnolence, ataxia, and respiratory and cardiovascular depression.

FOLLOW-UP

Section 8 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

Further Outpatient Care

• Communicate initiation of drug treatment or any change in therapy to the physician responsible for ongoing care.

In/Out Patient Meds

• TN may be a recurrent problem. Many patients obtain some relief with carbamazepine and/or baclofen. Medications may be changed at ED visits, but communicate changes to other caregivers.

Complications

• Mental and physical sluggishness and dizziness occur with use of carbamazepine.

Prognosis

• The disease course is typically one of clusters of attacks that wax and wane in frequency.
• Exacerbations most commonly occur in fall and spring.

Patient Education

• Trigeminal Neuralgia Association
  925 Northwest 56^th Terrace
  Gainesville, FL 32605-6402
  Telephone: (352) 331-7009 or 1 (800) 923-3608
• For excellent patient education resources, visit eMedicine's Brain and Nervous System Center. Also, see eMedicine's patient education articles Trigeminal Neuralgia (Facial Nerve Pain) and Tic Douloureux.

MISCELLANEOUS

Section 9 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

Medical/Legal Pitfalls

• Erroneous diagnosis of TN when another condition is present
• Presumptive diagnosis of idiopathic TN when, in fact, facial pain is secondary to another process (see Pathophysiology)

Special Concerns

• TN is not life threatening. If atypical features (eg, abnormal neurologic examination findings) are present, consider consultation, referral, and/or diagnostic imaging.

REFERENCES

Section 10 of 10

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

1. Fromm GH, Terrence CF, Maroon JC. Trigeminal neuralgia. Current concepts regarding etiology and pathogenesis. Arch Neurol. Nov 1984;41(11):1204-7. [Medline].
2. Zvartau-Hind M, Din MU, Gilani A, Lisak RP, Khan OA. Topiramate relieves refractory trigeminal neuralgia in MS patients. Neurology. Nov 28 2000;55(10):1587-8. [Medline].
3. Bennetto L, Patel NK, Fuller G. Trigeminal neuralgia and its management. BMJ. Jan 27 2007;334(7586):201-5. [Medline].
4. Campbell JK. Trigeminal neuralgia: are all of the treatment options being considered?. Headache. Jan 1997;37(1):H3. [Medline].
5. Cheshire WP Jr. The shocking tooth about trigeminal neuralgia. N Engl J Med. Jun 29 2000;342(26):2003. [Medline].
6. Chole R, Patil R, Degwekar SS, Bhowate RR. Drug treatment of trigeminal neuralgia: a systematic review of the literature. J Oral Maxillofac Surg. Jan 2007;65(1):40-5. [Medline].
7. Gouda JJ, Brown JA. Atypical facial pain and other pain syndromes. Differential diagnosis and treatment. Neurosurg Clin N Am. Jan 1997;8(1):87-100. [Medline].
8. Jackson EM, Bussard GM, Hoard MA, Edlich RF. Trigeminal neuralgia: a diagnostic challenge. Am J Emerg Med. Oct 1999;17(6):597-600. [Medline].
9. Kubitz PK, Wijdicks EF, Bolton CF. Tic douloureux or "tic dentaire". Neurology. Jan 27 2004;62(2):333. [Medline].
10. Liu JK, Apfelbaum RI. Treatment of trigeminal neuralgia. Neurosurg Clin N Am. Jul 2004;15(3):319-34. [Medline].
11. Rasche D, Kress B, Schwark C, Wirtz CR, Unterberg A, Tronnier VM. Treatment of trigeminal neuralgia associated with multiple sclerosis: case report. Neurology. Nov 9 2004;63(9):1714-5. [Medline].

Article Last Updated: Aug 28, 2007