Understanding Trigeminal Neuralgia

What is trigeminal neuralgia?

We each have 12 pairs of important nerves that run from the brain into the head and neck. These nerves play a variety of roles, including regulating our senses and controlling our facial muscles.

One of these pairs of nerves, known as both the fifth cranial nerve and the trigeminal nerve, transmits sensations from the face to the brain. If the trigeminal nerve becomes damaged or stops working properly, it can cause an intensely painful medical condition called trigeminal neuralgia.

In people with trigeminal neuralgia, any type of facial stimulation — including smiling, chewing and being outdoors on a windy day — can trigger extreme jolts of pain in the face.

In the early stages of the disease, pain attacks may be short and mild. Over time, however, the attacks can occur more frequently with each episode lasting for longer periods of time.

What causes trigeminal neuralgia?

The trigeminal nerve can start to malfunction for a variety of reasons, including:

• Aging – Trigeminal neuralgia usually occurs in people over 50.
• Gender – The condition is more common in women than men.
• Medical conditions – Certain disorders including multiple sclerosis can damage the protective coating that surrounds the trigeminal nerve (called the myelin sheath). In some cases, a blood vessel or tumor presses up against the trigeminal nerve, and the constant pressure and friction causes the myelin sheath to wear away.
• Injury – Sometimes the trigeminal nerve can be damaged during oral or facial surgery, or after a traumatic injury to the face.

What are the symptoms of trigeminal neuralgia?

There are two different varieties of trigeminal neuralgia. Most people who have the disease are diagnosed with Type 1, also known as classic trigeminal neuralgia.

Type 1 symptoms include intermittent spasms of stabbing pain, often described as feeling like an electric shock, that come on suddenly and last anywhere from a few seconds to two minutes per episode. While these short episodes can repeat in quick succession for up to two hours, the pain generally goes away for a period of time.

Among people with Type 2, also known as atypical trigeminal neuralgia, the pain is not quite as severe but it is constant (often described as an aching or burning sensation).

The pain associated with both types of trigeminal neuralgia is often felt in the cheek, jaw, teeth, gums or lips. It can be triggered by any amount of facial stimulation, including:

• touching your face
• putting on makeup
• shaving
• brushing your teeth
• eating or drinking
• talking
• smiling
• feeling a breeze
• showering

Because trigeminal neuralgia is considered a progressive condition, the pain attacks eventually can become more frequent and intense.

How is trigeminal neuralgia diagnosed?

If your doctor suspects you have trigeminal neuralgia, he or she will perform tests to rule out other medical conditions that cause facial pain, and confirm a diagnosis. These tests include:

• A neurological assessment that includes a physical examination of your face. By touching parts of your face, your doctor can better determine where the pain is occurring and what portions of the trigeminal nerve are affected.
• A magnetic resonance imaging (MRI) scan to capture 3-D images of your head. An MRI can detect whether there is a blood vessel or tumor pressing up against the trigeminal nerve, or whether multiple sclerosis or another neurological condition has caused the myelin sheath surrounding the nerve to deteriorate. Your doctor may use a variation of this test, called MR angiography or MRA, to examine the blood vessels in your head in greater detail (for example, to determine the severity of compression caused by a blood vessel resting against the trigeminal nerve).

How is trigeminal neuralgia treated?

If your doctor confirms you have trigeminal neuralgia, he or she will create a treatment plan that includes one or more of the options below.

Medications

Medications are often the first course of treatment for trigeminal neuralgia, although they may be used in combination with other therapies including surgery. Some of the different kinds of medications commonly prescribed to treat trigeminal neuralgia include:

• Anticonvulsant drugs including carbamazepine are used to block the trigeminal nerve from firing. While this type of medication is often effective at relieving pain, especially among people with Type 1 trigeminal neuralgia, over time it can lose its effectiveness (meaning your doctor will need to increase the dose or switch you to a different type of drug).
• Antispasmodic agents are a type of drug that causes the muscles to relax. It is often used in combination with an anticonvulsant drug, but it may be used alone.
• Tricyclic antidepressants including amitriptyline often are more effective at relieving the extreme pain associated with trigeminal neuralgia than traditional pain medications such as aspirin or ibuprofen.

Surgery

Since trigeminal neuralgia is a disease that gets progressively worse over time, medication may eventually lose its effectiveness. If your pain can no longer be managed with medication alone, or your medication causes unpleasant side effects, your doctor may recommend one of the following surgical procedures:

• Microvascular decompression is a procedure used to move (or remove) any arteries or veins pressing up against the trigeminal nerve. In order to do this, your surgeon will first make a tiny incision behind an ear, then drill a small hole in the skull. Through this opening he can move the offending arteries away from the trigeminal nerve, and keep them separated by placing a small pad between them. If there is a vein compressing the nerve, the surgeon may completely remove it.

Another form of surgery, called a rhizotomy, damages or destroys fibers within the trigeminal nerve (nerve fibers help carry sensation from the nerves to different parts of the body). There are several different types of rhizotomy:

• During balloon compression, your surgeon will insert a hollow needle through your cheek and gently guide it to the portion of the trigeminal nerve that passes through the base of your skull. He will then thread a tiny, flexible tube called a catheter through the hollow center of the needle. The catheter will have a balloon attached to its tip. Once the catheter and balloon are in place, your surgeon will inflate the balloon with enough force to firmly squeeze the nerve against your skull. This activity damages the trigeminal nerve and blocks its pain signals.
• During glycerol injection, your surgeon will pass a needle through your cheek into an opening at the base of your skull. He will guide the needle into a small pocket of spinal fluid (called a cistern) that surrounds part of the trigeminal nerve root. Once the needle is in place, your surgeon will inject a solution called glycerol, which damages the nerve fibers and blocks pain signals.
• During radiofrequency thermal lesioning, your surgeon will insert a hollow needle through your cheek and gently guide it to the portion of the trigeminal nerve that passes through the base of your skull. He will thread an electrode through the needle, then deliver an electrical current to the tip of the electrode. The heat produced by the electrical current injures the trigeminal nerve fibers and blocks pain signals.

No matter what type of rhizotomy you have, once the trigeminal nerve fibers are damaged you will experience some degree of long-term facial numbness.

It's important to note that although surgery may successfully alleviate the pain caused by trigeminal neuralgia, over time the pain may gradually return, requiring you to undergo another procedure or seek an alternative type of treatment.

Radiation therapy

Radiation therapy is used to treat a variety of neurological disorders, including brain tumors and arteriovenous malformations. It uses radiation in several forms, including X-rays, Gamma rays and protons, to damage or destroy abnormal cells, blood vessels or nerves.

A form of radiation therapy called Gamma Knife radiosurgery is especially effective at reducing or eliminating the pain associated with trigeminal neuralgia. Despite what the name implies, it is not surgery in the traditional sense because the procedure does not require cutting or an incision.

Instead, multiple beams of radiation are simultaneously aimed at the trigeminal nerve. The beams meet at the nerve root to deliver a single, massive dose of radiation that damages the nerve and its ability to send signals to the brain.

If your condition gets worse and your pain eventually returns, Gamma Knife radiosurgery can be repeated.

Trigeminal neuralgia care at Lyerly Neurosurgery

Since Lyerly Neurosurgery was founded in 1934, our physicians have cared for thousands of people who need treatment for a brain or spine condition.

Today our practice continues to build upon a legacy that blends compassion, safety and innovation. In partnership with Baptist Medical Center Jacksonville, our physicians routinely collaborate with neurologists and other physicians who have referred their trigeminal neuralgia patients to us for surgery.

We understand how challenging, stressful and even frightening it can be to live with chronic pain, and together we are committed to helping you find long-term relief from your symptoms.