Trigeminal neuralgia is a painful condition of the trigeminal nerve, which is a sensory nerve taking sensations from the face to the brain. In this condition, patient has pain in the distribution of this nerve, i.e., any area of the face, not head.

What is the trigeminal nerve?

The word trigeminal implies that it has three parts. It is a sensory nerve taking information from one side of the face to the brain, including gums and teeth. Its main stem is close to the ear where it divides in three parts: the upper part goes to the forehead, the middle to the cheek (including the upper lip and the jaw), and the lower to the chin (including the lower lip and the jaw).

 

What is the meaning of neuralgia?

The word neuralgia means a painful condition due to a problem with a nerve. Pain of neuralgia can be triggered by touch or exposure to some other stimuli such as cold or heat. In trigeminal neuralgia, the trigeminal nerve is the affected nerve. In between attacks there may not be any pain. In comparison to neuralgia, pain of neuropathy is felt continuously.

 

Is trigeminal neuralgia hereditary?

In some cases, it can be. But in most cases, it is not, with many other causes. It is a rare condition, affecting women more than men.

 

What kind of pain occurs in trigeminal neuralgia? 

The pain of trigeminal can be a mild throb but it usually is a severe sharp electric-shock type, or a piercing knife-like pain. Typically, patients report jabs of electricity, or very sharp pain, at times lasting for a few seconds. It can also be called a referred pain because the area that hurts, the face, is not diseased. It is different from a pain from sinuses or a tooth infection. Typical triggers for this pain are talking, chewing, eating, putting makeup, shaving, drinking cold or hot water, or just an exposure to cold air. Pain of trigeminal neuralgia can be terribly depressing and requires urgent treatment. Once started, attacks may last for days to weeks to months. Pain is almost always one-sided. In case of two-sided pain, alternate cause should be explored.

 

What causes trigeminal neuralgia pain, and why it is so bad?

Imagine the nerve as an electric wire; if the coating of the nerve is injured, the inside part gets exposed. Anything touching that area, which may be a blood vessel or any structure around it, may trigger the pain. The reason for nerve injury can be mechanical pressure from a nearby blood vessel, or it can also be an inflammatory condition like multiple sclerosis. In a typical trigeminal neuralgia, the pain is not due to an infection, as in sinus or tooth infection, it is due to the injured and exposed area of the nerve.

 

Neurologists sometimes differentiate patients in three categories:

A: Classical trigeminal neuralgia: Caused by the pressure on the nerve from a blood vessel.

B: Trigeminal neuropathy: Caused by a condition like Multiple Sclerosis when the covering of the nerve and the nerve is affected, or in diabetic neuropathy. Rarely, a tumor around the nerve may also be the cause.

C: Trigeminal neuralgia of unknown cause: When no cause is determined.

 

How is trigeminal neuralgia diagnosed?

It is diagnosed by history of its peculiar pain and its triggers. In most cases of classical trigeminal neuralgia, examination does not reveal any abnormality. In cases of trigeminal neuropathy, sensory abnormality may be noted. MRI of brain with contrast, with special images of the area where trigeminal nerve is, can help to find a cause.

 

What is the cause of trigeminal neuralgia?

In most cases, trigeminal nerve is irritated by a near-by blood vessel. Sometimes it is due to an inflammatory condition like multiple sclerosis. In rare cases, it may also be a tumor disturbing the nerve. MRI is useful to find a mechanical cause like an artery touching the nerve, or a tumor, and a condition like multiple sclerosis.

 

What other conditions may look like trigeminal neuralgia?

Trigeminal neuralgia has its peculiar presentation that is unlike any other entity. Even then, it is important to consider post-herpetic neuralgia, giant cell arteritis, migraine, sinus infection, atypical facial pain syndrome (not the type described above), other local facial pathologies, including temporomandibular joint problems (TMJ), some rare headache syndromes (like SUNA and SUNCT), stone in the parotid or the salivary duct, or a dental ailment. Many of these conditions can easily be ruled out by clinical examination, e.g., if pain is affecting both upper and lower jaw, it is unlikely to be a tooth infection. If significant numbness or sensory loss is the issue, an MRI scan is warranted.

 

What is the treatment for trigeminal neuralgia?

Pain is the main issue in trigeminal neuralgia. This is neuropathic pain (pain from a nerve pathology), which does not respond to usual pain medicines. Most effective medicines for nerve pain are some used for epilepsy, such as carbamazepine. Some other seizure medicines may also help, such as oxcarbazepine, gabapentin, pregabalin, phenytoin, and some other similar medicines.

 

In emergency setting, IV fosphenytoin or lidocaine, in a hospital setting, or a nerve block (by a pain specialist) can be tried.

If medicines do not work, following treatments can be utilized:

1. 1. Decompressive surgery: Especially for a patient with MRI clearly showing the compressing blood vessels.
   2. Radiosurgery: In this technique, targeted rays are used to deactivate part of the nerve.
   3. Percutaneous lesioning of the nerve: In this technique, a needle is introduced to use a chemical or heat to damage part of the nerve.
   4. General surgery: In this technique, nerve roots are cut to stop signal transmission.

 

What should I do if I have trigeminal neuralgia?

Consult a neurologist to figure out if it is trigeminal neuralgia or something else. It is not uncommon for people to consult their dentist, an orthodontist, and an ENT surgeon before they come to see a neurologist. If there is no other sign of infection, it may be better to consult a neurologist right away to avoid any delay in diagnosis and treatment.

 

Where can I get more information about trigeminal neuralgia?

American Academy of Neurology