What Is Trigeminal Neuralgia?

Trigeminal neuralgia is the term used to describe pain related to the trigeminal nerve or one of its branches. The trigeminal nerve transmits impulses from the nerves in your face to your brain.  Trigeminal neuralgia is a chronic pain condition that affects this nerve causing even slight stimulation to the face to trigger unbearable pain. The exact source of trigeminal neuralgia is unclear. In some cases physicians may be able to determine cause from injury or damage to the nerves, or from centrally located changes in the brain, such as a migraine headache.

Migraine headaches are unbearably painful and might be felt on one side of the head behind the eye. A large portion of migraines happen on just the left or right side of the head and those linked with trigeminal neuralgia are commonly sporadic.  Approximately 16% of adults in the United States suffer from migraine headache. Those associated with trigeminal neuralgia are more established in women between the ages of 18 and 44 years. The pain linked with trigeminal neuralgia and migraines can be from sensitivity to light, sound, nausea, or vomiting.  Based on what patients report, some researchers believe the pain associated with TN may be the worst experienced by humans.

Causes Of Trigeminal Neuralgia

The cause of chronic pain from trigeminal neuralgia can be the result of injury to the trigeminal nerves. In some cases it is also the result of injury to the trigeminal nucleus situated in the brain.  Some individuals can experience trigeminal neuralgia following facial injury or associated with migraine headaches. In other cases, damage may be associated with multiple sclerosis, scleroderma, herpes zoster (shingles), or lupus. In one theory, researchers are exploring the idea that trigeminal neuralgia is the result of the deterioration of the protective layer surrounding the nerves. This may be an explanation for those instances in which physicians are unable to find any other reasons for the condition.

Treatments For Trigeminal Neuralgia

When the cause for trigeminal neuralgia is an inflammatory response, prescriptions for non-steroidal anti-inflammatory medications (NSAIDs), such as aspirin or naproxen, can be the first-line medical treatment. The use of these medications appears to be more effective in individuals who experience episodic migraines on ten days or less per month. NSAIDs may result in organ failure when they are used consistently over a long-term period of time. In higher doses, acetaminophen may also be credible in treating mild episodes of migraines that are associated with trigeminal neuralgia. However, taken regularly or in excess, acetaminophen can also cause liver failure.

In some patients, prescriptions for opioid drugs are used to control pain.  These drugs trigger receptors in the spinal nerves in order to inhibit the transmission of pain signals.  Usual types of opioids prescribed include fentenyl, codeine, and morphine.  Although effective in some populations, they are related to a higher risk of drug tolerance and addiction. Individuals using opioids for the treatment of migraines may find a rebound effect occurs when they discontinue using them. This means the migraine symptoms can become much worse when the individual suddenly stops using the medication.

Carbamezapine may also be prescribed for intermittent migraines and is an anti-seizure medication.  This medication has more significant side effects, including skin irritation, allergic reactions, and toxic epidermal necrolysis.  Reactions of this type are found more frequently in native Asian individuals.

The trigeminal nerve splits into three divisions. These divisions unite into a single grouping situated behind the eyes. The group of nerves is called the semilunar ganglion or trigeminal Gasserian. In some cases, physicians may target this area using a minimally intrusive surgical treatment to reduce or completely relieve severe pain that has not responded to other more conservative treatments.  One type of procedure used is radiofrequency ablation done with a thin probe introduced through the nose or mouth.  A local numbing agent is injected prior to starting the procedure during which the ganglion is found using imaging technology.  Fluoroscopy or magnetic resonance imaging is used to locate the area, while the probe is inserted and electro-thermal impulses are discharged, which selectively eliminates the nerve tissue accountable for the signals of pain.

Radiofrequency ablation results in immediate pain relief in close to 97% of patients suffering from migraines.  The risks related to this procedure are infection, the potential for reduced sensation or motor control in the facial area, and discomfort with the insertion of the probe. Even with local anesthesia, some individuals may experience extreme pain with the insertion of the surgical probe.

Conclusion

Trigeminal neuralgia is a disorder of the trigeminal nerves that causes extreme pain. Treatment may include opioids and non-steroidal anti-inflammatory medications. If these treatments fail to bring about sufficient pain relief, other more invasive surgical procedures may be considered by the physician to achieve effective and long-term pain relief.  One such procedure is the radiofrequency ablation. During this procedure electro-thermal impulses are used to destroy the region of the trigeminal ganglion that is responsible for transmitting pain signals to the brain.  This particular technique has reported results up to 97% success rate.

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