What is Trigeminal Neuralgia?
Trigeminal Neuralgia
Trigeminal neuralgia (TN) is a distinctive and severe type of face pain that can be extremely hard to live with. It involves irritation of the trigeminal nerve and can cause intense pain on one side of the face and forehead. The sudden pain of trigeminal neuralgia can stop you in your tracks.
What Is the Trigeminal Nerve?
The trigeminal nerve is the fifth of twelve cranial nerves, the nerves that come directly from the brain and brainstem to serve the head and neck. Its main job is to carry sensation from your face to your brain. You have two trigeminal nerves, one on each side of your face. Each nerve has three branches, which is where the “tri” in its name comes from. The three branches serve these areas of the face (1):
The ophthalmic branch (V1) carries sensation from the eye, upper eyelid and forehead.
The maxillary branch (V2) carries sensation from the lower eyelid, nostril, upper lip, upper gum and cheek.
The mandibular branch (V3) carries sensation from the jaw, lower lip and lower gum, and it also controls some of the chewing muscles.
Trigeminal neuralgia, sometimes called tic douloureux, happens when one or more of these branches becomes irritated, causing excruciating pain. It usually affects one side of the face. The lower face and jaw are most often involved, but sometimes the pain affects the area around the nose and above the eye. The pain is intense, stabbing or shock-like (2).
How Common Is Trigeminal Neuralgia?
Trigeminal neuralgia is rare. About 12 in every 100,000 people are diagnosed with it each year (1). It can happen at any age but is more common after age 50, and it affects women more often than men (3). It usually isn’t inherited, but a small percentage of cases appear to run in families (4).
What Are the Early Signs of Trigeminal Neuralgia?
Early signs of TN are short bursts of severe, shooting or stabbing pain on one side of the face, usually in the cheek or chin. These attacks may seem to come out of nowhere and may last a few seconds or several minutes. Common triggers include (3):
Shaving
Touching your face, or clothing brushing against it
Eating or chewing
Brushing your teeth
Smiling
Washing your face
Putting on makeup
Wind or a cold breeze
Talking
Drinking
What Are the Later Symptoms of Trigeminal Neuralgia?
Over time, attacks may last longer or happen more often. Trigeminal neuralgia can become disabling as it progresses.
What Causes Trigeminal Neuralgia?
Researchers have identified several causes of TN, which are grouped into three types (5):
Classic trigeminal neuralgia. A blood vessel presses on the trigeminal nerve, which can irritate it and damage its protective coating.
Idiopathic trigeminal neuralgia. The cause is unknown, and testing doesn’t find a clear reason.
Secondary trigeminal neuralgia. TN is caused by another condition, such as multiple sclerosis, a tumor near where the nerve leaves the brainstem, shingles, a facial injury, stroke or inflammation.
Research from 2020 has also found genetic changes affecting GABA signaling or ion channels in nerve cells in some people with TN (6).
What Happens in the Nervous System With Trigeminal Neuralgia?
The most common cause of TN is damage to myelin, the protective coating around nerve fibers, usually where the trigeminal nerve root leaves the brainstem. Myelin insulates nerves and helps signals travel quickly. When a nearby artery or vein presses on the nerve root, it can wear away this coating. The nerve can then become unstable and overexcitable, firing abnormally and producing severe pain (7).
When there’s no blood vessel pressing on the nerve, TN may be caused by a condition that damages the brainstem, such as multiple sclerosis (8), or by a tumor where the trigeminal nerve leaves the brainstem, an area called the cerebellopontine angle (9). Newer research suggests that in some people, genetic factors may affect how the nerve itself works (10).
Medications that affect sodium channels or the calming brain chemical GABA can help people with TN, and genetic research is starting to explain why. Studies have linked TN to a common variation in the serotonin transporter gene and to genes involved in GABA. GABA normally calms nerve activity, and too little of it can make sensory nerves overexcitable (11). Research suggests this may allow more of the excitatory brain chemical glutamate to build up, strengthening the pain signal the trigeminal nerve sends to the brain (12).
How Is Trigeminal Neuralgia Diagnosed?
Trigeminal neuralgia is diagnosed with a detailed medical history and physical exam, which help identify any serious underlying condition that could be causing secondary TN. A neurological exam helps determine the cause and guide treatment. An MRI is recommended to help identify the type of TN and rule out other causes (13).
How Is Trigeminal Neuralgia Usually Treated?
TN is usually treated first with anti-seizure medications, such as carbamazepine and oxcarbazepine, which calm overactive nerves (14). When a blood vessel is pressing on the nerve, surgery may be used to relieve that pressure. However, MRI can’t always tell which contacts between blood vessels and the nerve are actually causing symptoms (5). Other procedures are also available for some people.
How the NeuroRescue Program Can Help
Our care is designed to work alongside your neurologist, neurosurgeon and other providers, never in place of them. Please don’t change or stop your medications without talking with your prescriber. If you have new face pain along with numbness, weakness, vision changes or trouble speaking, get medical care right away.
The goal of our care is to support the function of the nervous system involved in TN, with the aim of reducing pain and making everyday activities more comfortable.
Much of what happens in TN is related to how the nervous system responds to touch and other sensations on the face. The vagus nerve connects with the trigeminal system in the brainstem. In an animal study, non-invasive vagus nerve stimulation reduced the release of glutamate in the trigeminal pain pathway by about one-third (12). Based on this research, your program may include non-invasive vagus nerve stimulation.
The brainstem area where the trigeminal nerve begins also helps control certain eye movements, and these may be affected in some people with TN. Two types are especially important. Saccades are fast eye movements that shift your gaze from one target to another, and they need to be fast, accurate and quick to start. The vestibulo-ocular reflex (VOR) keeps your vision steady when your head moves, and it needs to match your eye movements precisely to your head movements. Because the brainstem is involved in both, our testing measures them carefully, and your program may include precise exercises to train them, with the goal of supporting brainstem function.
Depending on your needs and test results, your program may also include:
Vestibular rehabilitation to support brainstem function (15).
Mirror therapy, including mirror feedback in a virtual reality environment, which has been studied as a way to help the brain remap sensation in the face and reduce pain (16, 17).
Electrical stimulation to support pain modulation (18, 19).
Cold laser therapy applied to the skin over the trigger area (20).
Transcranial magnetic stimulation (TMS), which has been studied for neuropathic pain and can also help with the anxiety and depression that often come with chronic pain (21, 22). At our clinic, TMS is provided by our psychiatric mental health nurse practitioner, who will evaluate whether it may be appropriate for you.
Some programs include mild hyperbaric therapy as a structured recovery option between more demanding therapy sessions.
No two cases of trigeminal neuralgia are alike, and the same is true for your NeuroRescue Program. The therapies we recommend are always chosen based on your testing and exam findings.
How the NeuroRescue Program Works
Your NeuroRescue Program begins with your Discovery Day. We start with a detailed history of your condition and your life on a timeline. This helps us understand the factors that may have contributed to where you are now, and identify related conditions that may be making it harder to move forward. If structural causes of your TN haven’t been ruled out, we’ll make sure that happens with the right specialists.
We measure how your visual, vestibular and balance systems are working through computerized analysis of your eye movements, inner ear reflexes and balance under different conditions. Our testing includes videonystagmography and saccadometry to measure several types of eye movements, the video head impulse test to measure inner ear reflexes, and CAPS computerized posturography to assess your balance under different sensory conditions. We also use NeuroSensoryMotor Integration testing to evaluate hand-eye coordination and cognition, and Virtualis testing to assess dynamic eye tracking and your perception of vertical in a virtual reality environment.
We combine this with a thorough physical and neurological exam of your sensory, motor, autonomic and cognitive systems. We also review any relevant lab work, imaging and prior testing, and integrate it with our findings.
Together, this helps us understand which parts of your nervous system are working well, which are struggling, and how quickly they tire. We use that information to design your personal NeuroRescue Program, aimed at improving function in the systems that need support and helping them work together. Our testing also helps us decide when to push and when to let you rest.
Our goal is to help you get your symptoms under better control, so everyday moments like eating, talking and feeling a breeze on your face can become more comfortable again.
Your Next Step
Living with trigeminal neuralgia can be exhausting and debilitating, but there are options worth exploring. To find out if the NeuroRescue Program is right for you, contact one of our patient care coordinators to schedule your Discovery Day.
It’s never too late to take the next step.
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