Net Guide: Trigeminal Neuralgia

Pain Management, June 2010, Volume 3, Issue 4

A collection of links and resources from across the web focused on one specific condition. These resource range from useful websites to clinical trials.

//The Educated Patient™

Trigeminal Neuralgia Fact Sheet

Direct your patients to this site to read about trigeminal neuralgia. Here, patients can learn how the disorder is defined, where the trigeminal nerve is located and its biological role, what causes the disorder, and the symptoms one can expect, as well as diagnosis and treatment options. Under the “Symptoms” header, patients can learn about triggers that can cause pain. For example, the site explains that “The intense flashes of pain can be triggered by vibration or contact with the cheek (such as when shaving, washing the face, or applying makeup), brushing teeth, eating, drinking, talking, or being exposed to the wind.” In the “How Is it Treated?” section, the site covers the many different treatment options, including surgical interventions like rhizotomy. The site goes onto explain what is to be expected when undergoing a rhizotomy—including the likelihood that the procedure “causes some degree of permanent sensory loss and facial numbness”—and goes over the many different types of rhizotomy, including balloon compression and glycerol injection.

Trigeminal Neuralgia

This site provides a detailed review of trigeminal neuralgia, noting that the condition “is sometimes described as the most excruciating pain known to humanity.” Here, patients can learn what causes the “intense, stabbing, electric shock-like pain” and what treatment options are currently available. The site describes, in detail, the three branches that the trigeminal nerve divides into after leaving the brain and traveling into the skull. It explains that the first controls “sensation in your eye, upper eyelid, and forehead;” the second controls “sensation in your lower eyelid, cheek, nostril, upper lip, and upper gum;” and the third controls “sensations in your jaw, lower lip, lower gum,” and some muscles involved in chewing.

About Neuropathic Facial Pain and TN (Trigeminal Neuralgia)

Featured here is a detailed illustration and diagram of the nerves involved in trigeminal neuralgia. The site, provided by The Facial Pain Association, offers articles describing TN, neuropathic facial pain, and dental issues. The “Neuropathic Face Pain and Trigeminal Neuralgia Tip Sheet” features tips from patients. The site is careful to mention that the tips are intended for informational purposes and not to replace the advice of qualified professionals. The “Diagnostic Questionnaire,” provided by the Oregon Health & Science University, provides yes-or-no questions that can be scored to determine if a patient is most likely suffering from TN. Among the questions: “Do you have any constant background facial pain (eg, aching, burning, throbbing, stinging)?” and “Did your pain start after a facial injury?”

What Is Trigeminal Neuralgia?

This video explains trigeminal neuralgia, who it affects, the prevalence of the disorder, and the symptoms. It offers key points of information, including the fact that the “syndrome usually develops in individuals over 50 years old and occurs in approximately 4/100,000 individuals.” Additionally, the video explains that “painful attacks may occur spontaneously, but are more often associated with a specific stimulus in a ‘trigger area.’” The site is “written and edited by board-certified physicians from a variety of different specialties.”

//Medical Websites

Trigeminal Neuralgia

Physicians looking to refresh their memories on the basics of trigeminal neuralgia should check out this article, featured on the American Academy of Family Physician’s website. The overview, written by Rudolph M. Krafft, MD, discusses the pathophysiology, diagnosis, and treatment of the syndrome. A number of features accompany the text, including a drawing of the trigeminal nerve; tables, including “Key Recommendations for Practice;” and diagrams, including a “Diagnosis and Treatment of Trigeminal Neuralgia” flow chart.


Cardiovascular Response during Trigeminal Ganglion Compression for Trigeminal Neuralgia According to the Use of Local Anesthetics

Journal: Acta Neurochirurgica (May 2010)

Authors: Tibano A, de Siqueira S, da Nóbrega J, Teixeira M

Purpose: To “investigate cardiovascular parameters (blood pressure and heart rate [HR]) of patients that underwent trigeminal balloon compression with local anesthetics compared to a control group (placebo).”

Results: The “means of systolic and diastolic blood pressures (SBP and DBP, respectively) were higher in the control group when compared to the study group” at the evaluation during puncture with catheter and balloon compression. The researchers concluded that the “use of local anesthetics during the trigeminal balloon compression for TN can have a preventive role for the risk of cardiovascular events.”

Severe Psychosocial Compromise in Idiopathic Trigeminal Neuralgia: Case Report

Journal: Pain Medicine (March 2010)

Authors: Siqueira S, Teixeira M, de Siqueira J

Purpose: To study the psychosocial compromise of idiopathic trigeminal neuralgia, based on the findings of a case report.

Results: The team focused on a case report involving a “60-year-old man with 17 years of idiopathic trigeminal neuralgia (ITN) which affected tooth brushing for six years, causing severe dental complications and psychosocial problems.” The patient underwent neurosurgery following diagnosis, “but after three months, pain recurred and was accompanied by dysesthesia and periodontal disease.” He then received dental treatment and “had complete alleviation of pain and no further need of medication over the following three years.” Researchers concluded that the patient’s “intense suffering” represents the importance of a multidisciplinary evaluation for pain-caused secondary complications. Additionally, “Appropriately trained health professionals are necessary to evaluate and treat these patients.”

Is it Effective to Raise The Irradiation Dose from 80 to 85 Gy in Gamma Knife Radiosurgery for Trigeminal Neuralgia?

Journal: Stereotactic Functional Neurosurgery (May 2010)

Authors: Kim Y, Kim D, Kim J, et al

Purpose: Researchers sought to “assess the effect of raising gamma knife radiosurgery (GKS) doses from 80 to 85 Gy for the treatment of trigeminal neuralgia (TN).

Results: “The authors retrospectively collected follow-up data of 104 GKS procedures conducted for TN. Doses of 80 and 85 Gy were prescribed for 60 and 44 patients, respectively.” Researchers found that “85 Gy brought more rapid clinical improvement

without causing more complications,” and seemed to be “preferable to 80 Gy, but prospective randomized trials are mandatory to get a more definite conclusion on the optimal dose for GKS of TN.”

Effect of Various Surgical Modalities in Recurrent or Persistent Trigeminal Neuralgia

Journal: Steretactic and Functional Neurosurgery (April 2010)

Authors: Han I, Shin D, Chang J, et al.

Purpose: The researchers sought to assess the effectiveness of various surgical modalities in recurrent or persistent trigeminal neuralgia.

Results: The team concluded that “percutaneous rhizotomy is recommended for most patients with recurrent pain after microvascular decompression, and MVD can be effective in patients with a history of failed percutaneous procedures. Radiosurgery can be utilized to treat those that have not responded to other surgical modalities.”

Injection of Botulinum Toxin Type A (BOTOX) into Trigger Zone of Trigeminal Neuralgia as a Means to Control Pain

Journal: Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology and Endodontics (March 2010)

Authors: Ngeow W, Nair R

Purpose: To evaluate whether botulinum toxin type A may be used to effectively treat the pain associated with trigeminal neuralgia.

Results: The article focuses on a case involving a “65-year-old female who did not respond to pharmacotherapy.” The patient suffered from a “persistent pain over the right

external nasal area and right mental region,” which was “relieved for several hours after daily injections of bupivacaine.” She was given a “trial of a single dose of 100 units of botulinum toxin type A (BOTOX) diluted in 2.5 mL saline,” which was “injected into the external nasal trigger zone (60 units) and to the mental nerve region (40 units).” The

patient was pain-free in the “external nasal region for five months,” but then the pain returned. The patient was again “injected with 100 units of botulinum toxin type A.”

Evaluation of the Pathophysiology of Classical Trigeminal Neuralgia by Blink Reflex Study and Current Perception Threshold Testing

Journal: Journal of Headache and Pain (June 2010)

Author: Liao M, Lee M, Hsieh M, et al.

Purpose: The researchers sought to evaluate the pathophysiology of Classical trigeminal neuralgia by blink reflex study and current perception threshold testing.

Results: The team recruited “49 patients with classical trigeminal neuralgia” and “divided them into an acute and chronic group.” They “used blink reflex study and current perception threshold (CPT) testing to evaluate the painful facial areas and contralateral non-painful areas of patients with classical TN.” According to the results, the team found that “classical TN is not a simple largemyelinated nerve fiber dysfunction but a more complex process with a main dysfunction of unmyelinated nerve fibers.”

//Clinical Trials Transcranial Magnetic Stimulation (TMS) Effects on Pain Perception

Study Type: Interventional

Age/Gender Requirements: 21-60 years (male/female)

Sponsor: Medical University of South Carolina

Purpose: “The purpose of this study is to investigate the effects of transcranial magnetic stimulation on pain perception.”

P h a r m a F o c u s

Tegretol XR (Carbamazepine)

eAbstracts Medical Management of Trigeminal Neuropathic Pains

Journal: Expert Opinion on Pharmacotherapy (June 2010)

Authors: Zakrzewska J

Purp ose: To cover trigeminal neuralgia and other neuralgic conditions in the face region, guidelines associated with the conditions, and “drug therapy for these relatively rare facial pains.”

Results: “Trigeminal neuralgia continues to be best managed using anticonvulsant drugs, the primary ones being carbamazepine and oxcarbazepine; baclofen may be helpful and, of the newly emerging drugs, pregabalin has potential.”

Clinical Trials

Efficacy and Tolerability of Carbamazepine CR in Diabetic Neuropathy Pain

Study Type: Interventional

Age/Gender Requirements: 18-65 years (male/female)

Sponsor: Novartis

Purpose: “The trial is designed to evaluate the efficacy and tolerability of carbamazepine in neuropathic pain in diabetic patients.”