Trigeminal neuralgia

Trigeminal Neuralgia 

Definition

Trigeminal neuralgia is a disorder of the trigeminal nerve (the fifth cranial nerve) that causes episodes of sharp, stabbing pain in the cheek, lips, gums, or chin on one side of the face.

Description

The trigeminal nerve, which is divided into three branches, is responsible for chewing, for producing saliva and tears, and for sending facial sensations to the brain. When this nerve breaks down for some reason, it can trigger brief but agonizing sizzles of pain on one side of the face.

This condition is unusual in those under age 50 and more often occurs after 70. Women are three times more likely to have the condition than are men. When trigeminal neuralgia does occur in younger people, it is often associated with multiple sclerosis.

The pain, while brief, is so severe that the sufferer often can't do anything else while the attack lasts. People with this pain often wince or twitch, which is where trigeminal neuralgia gets its French nickname tic douloureux, meaning "painful twitch."

Causes and symptoms

The origin of trigeminal neuralgia is not certain, but scientists believe it may be caused by degeneration,

Trigeminal neuralgia is a disorder of the trigeminal nerve (which is divided into three branches, as illustrated above) that causes episodes of sharp, stabbing pain in the cheek, lips, gums, or chin on one side of the face. The origin of this disorder is not certain, but scientists believe it may be caused by degeneration, pressure, or irritation of the trigeminal nerve.

(Illustration by Electronic Illustrators Group.)

pressure, or irritation of the trigeminal nerve. Some doctors believe the pain may be triggered by pressure from a nearby abnormally-formed artery lying too close to the nerve.

Any part of the three branches of the trigeminal nerve may be affected. Neuralgia of the first branch leads to pain around the eyes and over the forehead; the second branch causes pain in the upper lip, nose and cheek; the third branch causes pain on the side of the tongue and lower lip.

The first episodes are usually fairly mild and brief, and it may be minutes, hours, or weeks before the next attack. However, attacks tend to occur in clumps that may last for weeks at a time. As the sufferer ages, the episodes become more frequent and painful, until the person begins to live in constant fear of the next one.

The momentary bursts of pain usually begin from the same spot on the face each time. The pain can be triggered by touching the area, washing, shaving, eating, drinking, or even talking. Even a cool breeze across the face can set off an attack. Pain is more severe at the ends of the affected nerve, especially over the lip, chin, nostrils, or teeth.

Diagnosis

Diagnosis is usually made by eliminating other problems that could cause similar pain in teeth, jaw, head, or sinuses. Because patients with the condition tend to avoid trigger points, avoiding chewing, shaving, touching or washing their faces can be a clue to diagnosis of trigeminal neuralgia.

Treatment

It is not easy to treat trigeminal neuralgia. Pain can be suppressed by a range of medicines, including the anti-epilepsy medicines carbamazepine (Tegretol) or phenytoin (Dilantin). These drugs slow down the nerve signals at certain nerve terminals, which eases the pain. However, these drugs cause a wide range of side effects, including nausea, dizziness, drowsiness, liver problems, and skin allergies. Some people develop resistance to the drugs or they can't tolerate the high dosage needed to control the discomfort. If the medicines are stopped, the pain usually returns.

If drug treatment fails, surgical treatment to block pain signals from the nerve may be effective. Radio-frequency waves, gamma rays, or glycerol injections can deaden the nerve (and hence the pain). An operation that frees the nerve from whatever is compressing it (blood vessel or tumor) can permanently relieve pain, but this major neurosurgical procedure carries its own risks and complications. Alternatively, a new procedure seeks to place a cushioning sponge between the nerve and a pulsating artery wrapping around it to soothe the irritated nerve.

Prognosis

Although the pain is momentarily incapacitating, it's not life-threatening. As the person ages, the attacks can be expected to occur more and more frequently.

Prevention

While the condition itself can't be prevented, there are a number of things patients can do to avoid triggering attacks:

Resources

Organizations

Chronic Pain Outreach. 822 Wycliff Ct., Manassas, VA 22110. (703) 368-7357.

National Chronic Pain Outreach Association, Inc. P.O. Box 274, Millboro, VA 24460-9606. (540) 997-5004.

National Institute of Neurological Disorders and Stroke. P.O. Box 5801, Bethesda, MD 20824. (800) 352-9424. http://www.ninds.nih.gov/index.htm.

Trigeminal Neuralgia Association. P.O. Box 785, Barnegat Light, NJ 08006. (609) 361-1014.

Key terms

Multiple sclerosis — A progressive disease of the central nervous system in which the coverings of nerves in the brain and spinal cord are destroyed.

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trigeminal neuralgia

n.

Paroxysmal shooting pains of the facial area around one or more branches of the trigeminal nerve, of unknown cause, but often precipitated by touching specific areas in or about the mouth. Also called Fothergill's disease, Fothergill's neuralgia, prosopalgia, prosoponeuralgia, tic douloureux, trifacial neuralgia.

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trigeminal neuralgia (trī·jeˑ·m·nl ner·alˑ·jē·),

n a condition in which the trigeminal facial nerve is subject to paroxysms. Presents clusters of stabbing pain that may be transient but that usually remain for hours. Caused by pressure or damage to any of the three branches of the trigeminal facial nerve.

Trigeminal neuralgia: distribution of trigger zones.

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trigeminal neuralgia,

n a neurologic condition of the trigeminal nerve characterized by paroxysms of flashing, stablike, unilateral pain radiating along the course of a branch of the nerve. Any or all of the three branches may be affected. The attacks are initiated by stimuli, such as a light touch of the skin, chewing, washing the face, or brushing the teeth. In some individuals the attacks may be initiated by painless physical stimulation of specific areas that are located on the same side of the face as the pain. Also called
tic douloureux.

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trigeminal neuralgia Neurology A condition characterized by stabbing paroxysmal unilateral neuropathic pain in absence of sensory or motor paralysis, of the 2^nd and 3^rd divisions of the 5^th cranial–trigeminal nerve; TN is most common in middle-aged ♀, evoked by touching trigger points, yawning, smiling, chewing, etc, or oral pathology, or regional tumors–eg, acoustic neuroma Management–medical Carbamazepine, phenytoin, alcohol injection Management–surgical If pain is intractable, microvascular decompression may be the most effective Other methods Extracranial neurectomy of trigeminal nerve branches, percutaneous heat ablation to produce trigeminal nerve or ganglion lesions–radiofrequency thermal rhizotomy, injection of glycerol into trigeminal cistern–retrogasserian glycerol rhizotomy, or physical compression–trigeminal ganglion balloon microcompression