What is Trigeminal Neuralgia?

Jul 28

Trigeminal Neuralgia, or TN, is a unique form of head and face pain that can be extremely difficult to live with. It involves sensitization of the trigeminal nerve, and can lead to severe pain throughout an entire side of the face and forehead. The sudden pain from trigeminal neuralgia can stop someone in their tracks.

What is the Trigeminal Nerve?

The trigeminal nerve is the fifth of twelve cranial nerves that leave the brainstem to control various functions in the head and neck. This specific nerve is responsible for providing the brain with sensation from the face. There are two trigeminal nerves, one on each side of the face. Each nerve has three distinct branches, hence “tri” being a part of the name. The three branches innervate the areas of the face as follows (1):

The Ophthalmic branch (V1) controls sensation in a person’s eye, upper eyelid and forehead.
The Maxillary branch (V2) controls sensation of the lower eyelid, nostril, upper lip, upper gum and cheek.
The Mandibular branch (V3) controls sensation in the jaw, lower lip, lower gum and some muscles used for chewing.

Trigeminal neuralgia (TN), sometimes called Tic Douloureux, occurs when one or more of the branches is irritated leading to excruciating pain. It is usually limited to one side of the face. The lower face and jaw are most commonly involved but sometimes it affects the area around the nose and above the eye. The pain is intense, stabbing or shock-like (21).

How Common is Trigeminal Neuralgia?

TN affects approximately 1 in 15,000 to 20,000 (12). It can occur at any age, but it is more commonly seen in people over age 50. While it is commonly not a genetic disorder, about 2% of cases appear to be familial (3). TN affects women more than men (6).

What are the Early Signs of Trigeminal Neuralgia?

Initial signs of TN are short episodes of severe, shooting or stabbing pain across one side of the face, usually on the cheek or chin. These may appear to be spontaneous and quickly resolve or last for several minutes. Triggering events include (6):

Shaving
Touching your face/clothing brushing against your face
Eating/chewing
Brushing teeth
Smiling
Washing the face
Putting on makeup
Wind/cold breeze
Talking
Drinking

What are the Later Symptoms of Trigeminal Neuralgia?

Later symptoms of TN include longer episodes or more frequent episodes in the TN distribution affected. Trigeminal Neuralgia can become disabling as it progresses.

What Causes Trigeminal Neuralgia?

There are a number of different causes for TN that have been identified, resulting in 3 different types of the disorder (4):

Classic Trigeminal Neuralgia: associated with vascular anomalies or anatomical structures creating an opportunity for blood vessels to compress the trigeminal nerve and cause irritation, demyelination and neuronal cell death.
Idiopathic Trigeminal Neuralgia: unknown cause, nothing is found on diagnostic testing.
Secondary Trigeminal Neuralgia: it occurs secondary to neurological disease, such as multiple sclerosis or tumors at the cerebellopontine angle, postherpetic infection (shingles), facial injury/trauma, stroke or inflammation.

There is also research from 2020 that has demonstrated a genetic mutation in either GABA signaling or neuronal ion transport in cases of TN (5).

What is Going on in the Brain with Trigeminal Neuralgia?

The most common cause of TN is demyelination of trigeminal sensory fibers within either the nerve root or, less commonly, the brainstem. Myelin is a protective sheath surrounding nerves that insulates them and allows fast conduction of impulses down the nerve fiber. Often an overlying artery or veinous malformation will lead to compression of the trigeminal nerve root, causing it to demyelinate. This promotes degenerative changes within the nerve, rendering it unstable and hyperexcitable. This instability leads to inappropriate frequencies of nerve firing that result in the perception of severe pain (22).

In the absence of this type of structural anomaly occurring, TN may be secondary to a disease process that is causing degeneration of the brainstem in a condition such as multiple sclerosis (23), or a tumor in the brainstem at the level where the trigeminal nerve exits (24), also called the cerebellopontine angle. Lastly, if there is a genetic component to TN, which very recent research is beginning to suggest, there may be dysfunction within the nerve itself (25).

Medications specifically addressing GABA production or sodium channels have been helpful to patients with TN. The underlying reason for the benefit of these medications is now being understood with genetic exome sequencing. A common single-nucleotide polymorphism (SNP) in the sodium dependent transporter responsible for serotonin transport, SERT, has been identified in correlation with TN. Other genes that have shown implication include genes related to the function of GABA production. GABA is typically an inhibitory neurotransmitter, and a lack of production has been demonstrated as leading to hyperexcitability in sensory nerves (7). This allows for increased levels of glutamate (excitatory neurotransmitter) to be present in the trigeminal nerve, and increase the signal it sends to the brain when it is stimulated (2).

How is Trigeminal Neuralgia Diagnosed?

Trigeminal neuralgia is diagnosed with a complete medical history and physical exam that can direct attention to any serious conditions that may be underlying and causing secondary trigeminal neuralgia. A neurological exam should also be performed to determine cause and create a treatment plan. Magnetic resonance imaging (MRI) should be ordered to differentiate TN category for the patient’s case (27).

How is Trigeminal Neuralgia Usually Treated?

Initial treatment of trigeminal neuralgia is usually medication for pain or inflammation management using medications such as Carbamazepine and Oxcarbazepine to decrease excitability of the neuron (26). If the cause is due to vascular compression, sometimes surgical interventions are used to remove the compression, however current MRI studies are not always efficacious at showing relevant vs. irrelevant contacts between blood vessels and the trigeminal nerve (4).

How Is the NeuroRescue Program Different?

Depending on the cause, we may be able to significantly reduce or resolve trigeminal neuralgia symptoms by employing a host of advanced therapies and technologies that can help improve the function of your remaining systems. By doing so, we can often help restore appropriate sensation to your face and provide comfort in activities that would normally be painless.

Much of what happens in TN is related to inappropriate levels of glutamate in response to sensory stimulus to the trigeminal nerve. The vagus nerve is linked with the trigeminal nerve within the brainstem. Research shows that non-invasive vagal nerve stimulation (nVNS) can reduce the amount of glutamate produced by sensory stimulus to the face by one third (2). We regularly use several forms of vagus nerve stimulation to help our TN patients get their symptoms under control.

Another important aspect of TN that is often overlooked is the general function of the brainstem, from which the trigeminal nerves emerge. The region of the brainstem that gives rise to the trigeminal nerve is also associated with the production of specific classes of eye movements. These are often dysfunctional in cases of TN.

In order for you to move through and interact with the world, you first need to know where the world is. You create your visual world with saccades, which are fast eye movements that shift gaze between targets. Vestibulo-ocular reflexes (or VORs) are reflexes that allow us maintain gaze stabilization on the world when the head is moving. Saccades need to be fast, accurate, stable, and have very quick reaction times. VORs need to be precise and have an appropriate balance of eye movement to head movement. As the brainstem is involved in both of these functions, the literature demonstrates that breakdown of these important reflexes occurs in patients with TN. We find that by rehabilitating saccades and VORs in a very precise manner, we can often improve function at the level of the brainstem, including function of the trigeminal nerve and reduce pain.

There are a host of other therapies that we engage in with our trigeminal neuralgia patients. All of these have different functions and allow us to rehabilitate specific capacities. These range from vestibular rehabilitation to improve brainstem function (28), to using therapies such as mirroring to remap sensation in the face and reduce pain (9). They include a number of different types of electrical stimulation to improve cognition, eye movements, and pain inhibition [10]. They may involve transcranial direct current stimulation to reduce pain (18, 19), They even include therapies such as transcranial magnetic stimulation to reduce pain and improve anxiety and depression surrounding the disorder (11), and cold laser therapy (13) directly to the skin area that triggers TN episodes.

No two trigeminal neuralgia presentations are alike, and the same holds true for the NeuroRescue program. A cookie-cutter approach will be doomed to fail in a condition as complicated as trigeminal neuralgia. All of our therapy protocols are tailored to the unique needs of the individual.

How Does the NeuroRescue Program Work?

We design your unique NeuroRescue Program to be the most comprehensive diagnostic and therapeutic protocol available today. We create individual NeuroRescue Programs based on a comprehensive analysis of every relevant neurological system and pathway, using gold-standard, cutting edge neurodiagnostic technologies and examination procedures and state-of-the-art therapies.

We begin with your Discovery Day, wherein we perform a comprehensive history of not only your condition, but your life on a timeline. This allows us to dive deeply into your case and see all of the factors that led to where you are now. It helps us uncover hidden problems and associated conditions that may be making it difficult for you to move your recovery forward.

In the case of trigeminal neuralgia, this requires a deep dive into the gut microbiome, intestinal wall permeability, exposure to toxins and other neuroinflammatory chemicals and many other factors that can be provoking your issues, following ruling out of other structural anomalies that may be the cause of your condition.

Our examination allows us to identify the areas and pathways of your brain that have been impacted to cause your trigeminal neuralgia. We begin by precisely quantifying the function of your visual, vestibular, and proprioceptive systems through computerized analysis of your eye movements, your inner ear reflexes, and your balance in a host of different sensory conditions.

We employ technologies including Videooculography and Saccadometry to measure several classes of eye movements. We use Video Head Impulse Testing to measure the function of your inner ear, and Computerized Dynamic Posturography to assess your balance in different sensory conditions.

We use NeuroSensoryMotor Integration testing to evaluate hand-eye coordination and cognition, and Virtualis testing to assess dynamic eye tracking and perception of vertical in a virtual reality environment.

We combine all of this with a comprehensive physical and neurological examination of your sensory, motor, autonomic, and cognitive systems. We review any relevant laboratory testing, radiological imaging, and prior neurodiagnostic testing, and integrate that information with our findings.

We use this information to identify which parts of your brain are working properly, which systems are struggling, and the precise point at which your systems fatigue.

We can then design a NeuroRescue Program that is unique and specific to your brain, and yours alone. Your NeuroRescue Program works to rejuvenate and reintegrate the damaged neurons and pathways in your brain. It works to improve energy, endurance, and functional capacity within your fragile systems.

Your therapy may include visual or vestibular exercises to restore function of the areas of the brain and brainstem that are involved in TN (14). They may involve specific forms of electrical therapies to facilitate pain modulation and normal trigeminal nerve function (15).

They may involve virtual reality mirror feedback to help you remap the sensory regions of your brain that become dysregulated in TN (16). They may include transcranial magnetic stimulation to modulate cortical excitability and decrease neuropathic pain (17). They may even include hyperbaric oxygen therapy to decrease pain and promote healing (20).

We use our technologies and procedures to not only see what we need to address, but also when it is time to stop and let you rest. We address your impaired neurological function from multiple angles of therapy, and provide metabolic support to improve neurological recovery.

Your NeuroRescue Program allows us to take the pathways that are inefficient and maximize their efficiency and endurance. And by focusing on the integration of systems, we can do more than just get pathways working better, we can get them working together again. This gives us our best opportunity to help you get your trigeminal neuralgia under control and return you to living a healthy, vibrant, and fulfilling life.

Your Next Best Step:

Living with trigeminal neuralgia is challenging and debilitating. Many of the symptoms can be manageable, function can be enhanced, and quality can often be significantly improved.

To see if the NeuroRescue Program is right for you, contact one of our patient care coordinators to schedule your Discovery Day.

And remember, it’s never too late to start getting better.