Trigeminal neuralgia

Content

Introduction

Trigeminal neuralgia is a disorder that causes severe pain in the face. Often, it is described as a sharp stabbing pain or as an electric shock to the jaw, teeth, or gums.

Usually, it comes on suddenly, with unpredictable painful episodes that can last from a few seconds to several minutes. The attacks stop as suddenly as they begin.

In most cases, trigeminal neuralgia affects part or all of one side of the face and the pain is located in the lower part. On rare occasions it can occur on both sides of the face, although not usually at the same time.

People with trigeminal neuralgia can have bouts of pain regularly, for days, weeks, or months. In severe cases they can occur multiple times a day.

It is possible for the pain to improve, or even disappear completely, for several months or years (remission), although the length of these periods tends to shorten over time.

Some people may develop more constant, throbbing pain and a burning sensation, sometimes accompanied by sharp attacks.

Living with trigeminal neuralgia can be very difficult. It can have a significant impact on a person's quality of life, causing problems such as weight loss, isolation and depression.

If you experience frequent or persistent facial pain and, in particular, if standard pain relievers such as acetaminophen and ibuprofen do not help and your dentist has ruled out any dental causes, you should consult your doctor. identify the problem, inquire about the disorders (symptoms) that have appeared and excluding other diseases that could be responsible for the pain.

However, ascertaining (diagnosing) trigeminal neuralgia can be difficult and can take a few years.

Trigeminal neuralgia is usually caused by compression of the nerve from which it takes its name, the trigeminal. It is located inside the skull and transmits pain sensations that start from the face, teeth and mouth up to the brain. Its compression is generally caused by a blood vessel pressing on the part of the nerve inside the skull.

In rare cases, trigeminal neuralgia can be caused by nerve damage caused by existing diseases such as multiple sclerosis (MS) or cancer.

Generally, pain attacks are triggered by actions related to brushing the face, such as rinsing or brushing the teeth, by a movement of the face and head but can also be caused by the wind. Even a light breeze or air conditioning is enough. Sometimes, the pain can occur in the absence of a specific cause.

It is unclear how many people are affected by trigeminal neuralgia, but it is believed to be a rare disease affecting around 5 in 100,000 people and that there are around 3,000 new cases each year. Women tend to be affected more than men and it usually occurs between the ages of 50 and 60. It rarely occurs in adults under the age of 40.

Trigeminal neuralgia is usually a long-term disease with periods of remission that often subside over time.However, most cases can be controlled with treatments that effectively relieve pain.

An anticonvulsant drug called carbamazepine, often used to treat epilepsy, is usually the first recommended treatment for trigeminal neuralgia.

For good results, carbamazepine must be taken several times a day with a dose gradually increasing over the course of a few days or weeks so that high enough levels of the drug can build up in the blood.

Unless the pain begins to subside, or disappear altogether, treatment must be continued for as long as necessary, sometimes for many years.

In periods in which pain is absent (period of remission), the interruption of treatment must always take place slowly, over the course of days or weeks, unless the doctor gives different recommendations.

Carbamazepine was not originally designed to treat pain, but it can help relieve it by slowing electrical impulses in the nerves and reducing their ability to transmit it. If it is ineffective, inadequate, or has too many side effects, you can ask a medical professional what alternative medications or surgical procedures will help.

There are some small surgeries to treat trigeminal neuralgia (usually the nerve is damaged to make it stop sending pain signals) but, generally, their effectiveness lasts a few years.

Alternatively, the specialist doctor may recommend surgery to remove any compressions of the blood vessels on the trigeminal nerve.

Research suggests that such an intervention offers the best results in terms of long-term pain relief.However, it is an important operation that carries a risk of potentially serious complications such as, for example, hearing loss, numbness of the face or, very rarely, bleeding.

Post-herpetic neuralgia is a more common type of nerve pain that usually develops in an area previously affected by shingles.

Symptoms

The main disorder (symptom) caused by trigeminal neuralgia is sudden intense pain in the face that lasts from a few seconds to several minutes. It is often described as excruciating, similar to an electric shock. The attacks can be so intense as to prevent any kind of occupation. It usually affects one side of the face. In rare cases it can affect both parties, although not at the same time.

Pain can occur in the teeth, jaw (upper mouth scaffold) or jaw (lower mouth scaffold), cheeks and, less commonly, forehead or eye.

Sometimes it is possible to perceive the arrival of an attack even if, usually, it manifests itself suddenly.

When the main pain has subsided, it is possible to feel a burning sensation or a slight pain. A constant throbbing, burning or pain may occur between attacks.

Painful episodes can occur regularly for days, weeks or months and then disappear completely and no longer appear for several months or years (remission period).

In severe cases, trigeminal neuralgia attacks can occur hundreds of times a day with no periods of remission.

Triggering factors

Attacks of trigeminal neuralgia can be triggered by certain actions or movements such as, for example:

  • speak
  • smile
  • to chew
  • Brush your teeth
  • wash your face
  • a light touch
  • shave or put on makeup
  • swallow
  • to kiss
  • a cool breeze or air conditioning
  • head movements
  • vibrations, like walking or taking a car trip

However, pain can occur spontaneously for no specific reason.

Living with trigeminal neuralgia can be very difficult and the quality of life can be significantly affected.

Those affected may no longer want to wash, shave or eat to avoid the pain and fear that this may occur can lead to avoiding social activities.

It is important to try to live a normal life and to be aware that malnutrition and dehydration can make the pain far worse.

The emotional tension associated with waiting for the pain crisis to repeat itself can lead to psychological problems, such as depression. During times of extreme pain, some people may even consider suicide. Even in periods of remission, one can live in the fear of the pain returning.

When to see the doctor

It is advisable to visit the treating doctor if frequent or persistent facial pain occurs, especially if conventional pain relievers such as, for example, paracetamol and ibuprofen do not help to relieve them and the dentist has ruled out any dental problems.

The doctor will try to identify the problem, inquire about the disorders (symptoms) present and rule out other diseases that could be responsible for the pain.

Trigeminal neuralgia can be difficult to ascertain (diagnose), so it is important to try to describe the complaints felt as accurately and in detail as possible to the doctor.

Causes

The exact cause of trigeminal neuralgia is not known but it is often thought to be caused by compression of the trigeminal nerve or by an already existing disease affecting it.

The trigeminal nerve, also called the fifth cranial nerve, is one of the largest in the head and is present on both sides of the face.

Pressure on the trigeminal nerve

Evidence suggests that in 95% of cases neuralgia is caused by pressure on the trigeminal nerve, located near the entrance to the brainstem (the lowest part of the brain that merges with the spinal cord). Generally, the pressure is caused by an "artery, or vein, which squeezes (compresses) the nerve at a particularly sensitive spot.

It is not clear why this pressure can cause painful attacks in some people but not in others. Not all those who have a compressed trigeminal nerve, in fact, suffer from neuralgia.

It could be that, in some cases, the pressure on the nerve wears down the outer protective layer (myelin sheath) causing uncontrollable pain signals that run throughout the nerve.

However, this does not clearly explain why one can experience periods without disturbances (symptoms) or why pain relief is immediate when, after a successful operation, the blood vessels are pulled away from the nerve.

Other causes that can compress or damage the trigeminal nerve include:

  • cancer
  • cyst , fluid-filled formation
  • arteriovenous malformation, abnormal tangle of arteries and veins
  • multiple sclerosis (MS), long-term disease affecting the nervous system

Diagnosis

Because the pain caused by trigeminal neuralgia is often felt in the jaw, teeth, or gums, many people initially see a dentist rather than a primary care physician.

To investigate the cause of the pain, the dentist may perform a dental x-ray and check that no other causes are present, such as a tooth infection or a broken tooth.

Trigeminal neuralgia is often ascertained (diagnosed) by the dentist but if the obvious cause of the pain does not emerge, it is recommended to see the primary care physician.

Visit to the general practitioner

The assessment (diagnosis) of trigeminal neuralgia is mainly based on the evaluation of the symptoms that have appeared and on the description of the pain.

The doctor will ask questions such as, for example:

  • the frequency with which pain attacks occur
  • the duration of the attacks
  • the affected areas of the face

The doctor will also evaluate other possible causes of the pain and will rule out that it can be caused by other diseases such as, for example:

  • migraine
  • articolar pains of the lower jaw
  • giant cell arteritis (temporal arteritis), inflammation of the medium and large arteries in the neck and head causing pain in the jaw and temples
  • possible nerve injury

In general, the patient's personal and family medical history should always be considered to determine the possible causes of pain. For example, although very unlikely, trigeminal neuralgia could also be an early symptom of multiple sclerosis (MS).

Magnetic resonance

If the primary care physician is unsure of the diagnosis, he may order magnetic resonance imaging (MRI) of the head. It is a study that uses strong magnetic fields and radio waves to create detailed images of the inside of the head. It can help identify possible causes of facial pain such as inflammation of the lining of the sinuses (sinusitis). , tumors that compress one of the facial nerves, damage to the nervous system caused by multiple sclerosis (MS).

MRI can also detect whether a cranial blood vessel is compressing one of the trigeminal nerves.

Therapy

Some treatments are able to offer some relief from the pain caused by trigeminal neuralgia. Identifying the triggers, in order to avoid them, can help.

Most people will be prescribed drugs to control pain, although surgery may be considered in cases where the drug is ineffective or causes too many side effects.

Avoid triggering causes

Painful attacks of trigeminal neuralgia can sometimes be caused, or aggravated, by some underlying cause. Knowing them helps prevent them.

If the pain is caused by the wind, wearing a scarf wrapped around the face may help. Even a clear dome-shaped umbrella can protect your face from the elements.

If the pain is triggered by drafts, it is recommended that you avoid sitting near open windows or sources of air conditioning.

Using a straw to drink hot or cold drinks can help prevent the liquid from coming into contact with the painful areas of the mouth. If you experience difficulty in chewing, it may be helpful to blend the foods or prefer those with a soft consistency. It is important to eat nutritious meals Certain foods such as caffeine, citrus fruits and bananas are believed to trigger attacks in some people, and therefore such foods should not be consumed by sensitive people.

Medicines

Because common pain relievers such as acetaminophen are not effective in treating trigeminal neuralgia, an alternative drug such as an anticonvulsant, usually used to treat epilepsy, may be prescribed to help relieve the pain.

Anticonvulsants were not originally designed to treat pain, but they can help relieve pain by slowing the electrical impulses of the nerve and reducing its ability to transmit pain.

They should be taken regularly, not just when the attacks occur, and can be stopped when the painful episodes stop (remission phase).

Unless otherwise instructed by the general practitioner or specialist, when starting to take medicines it is important to arrive at the prescribed dosage gradually as it is equally important not to suddenly stop taking them but gradually reduce the dose over the course of a few weeks.

Your primary care physician may initially prescribe a type of anticonvulsant called carbamazepine, although a number of alternatives are available if it is of little or no effect.

Carbamazepine

Carbamazepine is an anticonvulsant and is currently licensed as an essential drug for the treatment of trigeminal neuralgia. It can be very effective initially, but it can become less so over time.

Generally, it is necessary to take carbamazepine in low doses once or twice a day. The dose is gradually increased up to four times a day until pain relief is achieved.

Carbamazepine can induce undesirable effects (side effects) making its intake problematic in some cases. They include:

  • tiredness and sleepiness
  • vertigo (dizziness)
  • memory problems and difficulty concentrating
  • confusion
  • sense of instability when standing
  • nausea and vomit
  • double vision
  • reduction in the number of white blood cells that fight infections (leukopenia)
  • allergic skin reactions, such as hives

It is recommended that you speak to your primary care physician if you experience persistent or bothersome side effects while taking carbamazepine. In particular, if allergic skin reactions appear because they could be dangerous.

Carbamazepine has also been linked to a number of less common, but more serious side effects, including thoughts of harming or suicide. Should they occur, they must be reported immediately to the family doctor. If this is not possible, it is advisable to call 118.

Other drugs

Carbamazepine may be ineffective over time. In this case, or if significant side effects occur during its intake, it is advisable to contact a specialist for advice on other drugs or alternative procedures. Headache neurologists, neurosurgeons, and pain medicine specialists can be consulted.

In addition to carbamazepine, a number of other drugs are used to treat trigeminal neuralgia, including:

  • oxcarbazepine
  • lamotrigine
  • gabapentin
  • pregabalin
  • baclofen

None of these drugs have been specifically licensed to treat trigeminal neuralgia. This means they haven't undergone rigorous clinical testing to determine if they are effective and safe for treating this condition.

However, many specialists prescribe an unlicensed drug if they think it will be effective and the benefits of the treatment outweigh any associated risks.

If the doctor you are contacting intends to prescribe a drug without marketing authorization for the treatment of trigeminal neuralgia, he should give information and make known the possible risks and benefits. The side effects associated with most of these medicines can be very difficult to deal with at first. Not all people experience unwanted effects (side effects), but when this happens, it is advisable to insist as they often decrease over time, or at least until the next dose increase.

However, you should warn and seek advice from your GP if the side effects are intolerable.

Surgery and other nursing procedures

If the drugs do not adequately control the symptoms (symptoms) present or cause annoying side effects that last over time, a specialist can be referred to to inquire about the different possibilities, surgical and non-surgical, available to relieve pain. Before making a decision, you need to make sure that you understand the potential benefits and risks of each in order to choose the treatment that you consider the most appropriate.

If one cure does not work, you can try another or continue to take the drugs temporarily or permanently.

Percutaneous procedures

There are a number of treatments that can relieve, at least temporarily, the pain caused by trigeminal neuralgia. They consist of inserting a needle, or a thin tube, into the trigeminal nerve passing through the cheek. They are known as percutaneous procedures and are performed using X-rays to guide the needle or tube into the correct position. They are performed under general anesthesia or deep sedation.

Percutaneous procedures that can be employed to treat people with trigeminal neuralgia include:

  • injections of glycerol, consist of injecting a drug, called glycerol, around the Gasser ganglion, an area in which the three main branches of the trigeminal nerve join
  • radio frequency, involves the direct application of heat on Gasser's ganglion through the use of a needle
  • compression with a balloon, a technique that consists in squeezing the Gasser ganglion by means of a balloon, inserted in a thin tube, conveyed to the ganglion passing through the cheek. The balloon is then removed

These procedures work by intentionally damaging the trigeminal nerve to stop pain signals passing through it. Usually, after application, you are able to go home the same day.Overall, the procedures described are equally effective in relieving pain, although complications can occur with each, which vary according to the type of procedure and the characteristics of the individual who undergoes it.

Pain relief usually lasts only a few years or, in some cases, a couple of months. Results are rarely achieved.

The main undesirable effect (side effect) is numbness of part or all of the side of the face being treated. Its intensity can range from severe numbness to simple tingling. The sensation, which can be permanent, is often similar to that experienced after undergoing anesthesia at the dentist. Very rarely, it is possible to feel both numbness and continuous pain, a condition called painful, virtually incurable anesthesia.

The procedures indicated also carry a risk of other short- and long-term side effects and complications including bleeding, bruising on the face, eye problems and hearing problems on the affected side. Very rarely, they can cause strokes.

Stereotaxic radiosurgery

Stereotaxic radiosurgery is a new treatment that uses a concentrated beam of radiation to intentionally damage the trigeminal nerve where it enters the brain stem (the border area between the spinal cord and the brain). It does not require a general anesthetic or any cut (incision) on the cheek.

A metal frame is attached to the head with four pins inserted around the scalp after applying a local anesthetic to decrease the sensitivity of the area. The head, including the frame, is placed in a large machine that emits radiation for an hour or two. Thereafter, the frame and pins are removed and, after a short rest, you can go home.

Stereotaxic radiosurgery may take a couple of weeks or sometimes several months to take effect but can offer pain relief for some patients for several months or years. Studies related to stereotaxic surgery have shown similar results to the other procedures mentioned above.

Facial numbness and tingling in the face are the most common complications associated with stereotaxic radiosurgery. They can be permanent and, in some cases, very annoying.

Microvascular decompression

Microvascular decompression (MVD) is an "operation that can help relieve pain without intentionally damaging the trigeminal nerve. Instead, the procedure involves reducing the pressure exerted on the nerve by the blood vessels that touch or wrap around it. It involves opening the skull and is performed under general anesthesia by a neurosurgeon.

During the surgery, the surgeon makes an "incision in the scalp, behind the" ear, and removes a small circular bone fragment from the skull. Blood vessels are eliminated, or displaced, by separating them from the trigeminal nerve via an artificial tampon or scaffold constructed using adjacent tissue. For many sufferers, this type of surgery is effective and resolves, or completely stops, the pain of trigeminal neuralgia. It is able to give relief for longer; some studies suggest that pain only returns in about 30% of cases, within 10 to 20 years.

Currently, MVD is the most effective treatment for trigeminal neuralgia. However, it is an invasive procedure and carries a risk of potentially serious complications such as, for example, numbness of the face, hearing loss, stroke and even death in about 1 in 200 cases.

Further information and support

Living with a long-lasting painful condition, such as trigeminal neuralgia, can be very difficult.To receive advice and share information about the disease, it can be useful to get in touch with other patients who live the same experience.

A number of research projects have been launched in Italy and abroad to determine the cause of trigeminal neuralgia and identify new treatments and new drugs to treat it; the hope is that this serious painful condition can soon be combated more effectively.

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