Trigeminal Neuralgia

Types of trigeminal neuralgia

There are two types of trigeminal neuralgia:

• Type 1 (TN1) — classic trigeminal neuralgia
• Type 2 (TN2) — atypical trigeminal neuralgia

Causes of trigeminal neuralgia

Although the cause of trigeminal neuralgia is not well understood, typically trigeminal neuralgia occurs when the trigeminal nerve in the base of the brain is pressed on or irritated by a blood vessel.

The causes for the pressure and subsequent wearing away of the protective cover over the nerve may include:

• Presence of a brain tumor
• Multiple sclerosis
• Arteriovenous malformation
• Injury to the trigeminal nerve

A variety of movements that affect the face can trigger an attack such as applying makeup, brushing your teeth, washing your face, kissing, drinking, eating or touching your face.

Risk factors for trigeminal neuralgia

• Gender — trigeminal neuralgia affects women more often than men.
• Age — as people age, you are more likely to suffer from trigeminal neuralgia.
• High blood pressure (hypertension) — patients with high blood pressure are more likely to develop trigeminal neuralgia.
• Family history — if you have a parent with this condition, you are more likely to develop it as well.

Symptoms of trigeminal neuralgia

Symptoms of trigeminal neuralgia vary based on the type you have.

Symptoms of Type 1 (TN1)

Symptoms of trigeminal neuralgia Type 1 are typically more severe than those of Type 2. Facial pain caused by Type 1 comes on suddenly and is more intense. The pain feels like electrical shock to the face and can last as long as several minutes or can be as short as seconds. Typically, the shocks come in succession over a period of hours.

Symptoms of Type 2 (TN2)

Type 2 trigeminal neuralgia symptoms are constant and feel more like dull, stabbing or aching sensations. Type 2 trigeminal neuralgia is typically less severe than Type 1.

Some patients experience Type 1 and Type 2 trigeminal neuralgia at the same time which can cause excruciating pain.

Diagnosis of trigeminal neuralgia

Trigeminal neuralgia can be diagnosed by a neurologist. Your doctor will take a full medical history, evaluate your symptoms and perform a full physical and neurological exam. During the neurological exam, your doctor will touch your face in a variety of places to determine the location of the pain. The doctor will also check reflexes to try to determine if you have a compressed nerve.

Other tests to diagnose trigeminal neuralgia may include:

• MRI (magnetic resonance imaging) — an MRI can take detailed images of the brain and vessels to determine if you have a tumor, multiple sclerosis or other conditions that may be causing your symptoms.
• Short course of anti-seizure medications — if your doctor suspects you have Type 1 TN, he or she may prescribe anti-seizure medications to evaluate your response to the medications.
• Low doses of tricyclic antidepressant medications — some patients can be diagnosed with trigeminal neuralgia after taking low doses of tricyclic antidepressant medications to determine response.

Treatment of trigeminal neuralgia

Treatment for trigeminal neuralgia typically starts with medical management, and then if a patient is not responding, surgical approaches may be necessary.

Types of medication to treat trigeminal neuralgia

Some patients with trigeminal neuralgia can be managed on medications alone. Medications may include:

• Anticonvulsant — anticonvulsant medications are more effective for Type 1 trigeminal neuralgia; Carbamazepine is a commonly used anticonvulsant medication.
• Tricyclic antidepressants - these medications can be used to treat pain in Type 1 and Type 2 patients. These medications should be used cautiously and under direct supervision of a doctor.
• Antispasmodic agents - antispasmodic agents are used to relax the muscles. They can be used in conjunction with anticonvulsant medications.
• Botox injections - Botox injections have been proven effective in relieving pain associated with trigeminal neuralgia in patients who are not responding to medications.

Surgical options to treat trigeminal neuralgia

Microvascular decompression
During a microvascular decompression surgery, a surgeon will remove or move blood vessels that are compressing the nerve and causing it to malfunction. If your doctor can’t find any blood vessels pressing on the nerve, he or she may cut the nerve. In most cases, this procedure can successfully eliminate pain associated with trigeminal neuralgia. Your doctor will evaluate the benefits and risks with you as he or she discusses this procedure with you.

Gamma Knife radiation (stereotactic radiosurgery)
During a Gamma Knife procedure, focused radiation beams will be directed at the area of the trigeminal nerve that is causing your symptoms. The goal of the procedure is to damage the area of the nerve that is causing pain. Your symptoms may not be immediately relieved — symptom relief may take up to a month to occur.

Rhizotomy
During a rhizotomy procedure, nerve fibers are destroyed to eliminate the pain. There are three types of rhizotomy procedures including:

• Glycerol injection — during this procedure, your doctor will inject sterile glycerol into a sac of fluid that surrounds the trigeminal nerve where it divides into three branches.
• Balloon compression — during balloon compression, your doctor will insert a catheter with a balloon on it into the trigeminal nerve that goes through the base of the skull, when it is in the correct location, the balloon is inflated.
• Radiofrequency thermal lesioning — during a radiofrequency thermal lesioning procedure, your doctor will damage nerve fibers using mild electrical current directly to the area of the trigeminal nerve that is causing your symptoms.

Facial numbness after this procedure is common.