Trigeminal Neuralgia (TN)
What is trigeminal neuralgia (TN)?
Trigeminal neuralgia (TN) is a condition that can cause intense facial pain sometimes so severe it can interfere with the normal activities of daily living. Brief, painful episodes may be triggered by chewing, talking, smiling, brushing teeth, shaving, or light pressure on the face. The pain may be sudden, intense, and sporadic (off and on). It also may be more constant but less severe.
Usually, TN affects only one side of the face. In this case, it is said to be unilateral. If both sides of the face are affected, the condition is bilateral. The right side of the face tends to be affected slightly more often than the left side.
What is the trigeminal nerve?
The trigeminal nerve is responsible for transmitting sensations of touch and pain from the face and head to the brain. The trigeminal nerve has three branches. One branch carries nerve impulses from the forehead, upper eyelids, and eyes to the brain. The second branch is responsible for sensation in the lower eyelids, cheeks, nostrils, upper lip, and upper gum. The third branch serves the lower lip, lower gum, jaws, and some muscles used for chewing.
What are the types of trigeminal neuralgia (TN)?
There are two main forms of TN:
- Typical (Type 1) TN: Symptoms include sudden or sporadic periods of intense facial pain or burning. Attacks can last from a few seconds to a few minutes. Painful episodes occur in rapid succession and may continue for a few hours, but there are generally pain-free periods between attacks.
- Atypical (Type 2) TN: The atypical form is characterized by constant pain, with stabbing, burning or aching sensations that may be less intense but more widespread than those associated with Type 1. Symptoms may also be more difficult to control.
More about TN
TN may be progressive, meaning that the condition worsens over time. At first, pain may be limited to the upper or lower jaw, and patients might think it is due to dental problems. The intervals between attacks may become shorter or disappear altogether, while efforts to manage pain with medication may be less effective.
Pain that accompanies TN may be so intense that it becomes debilitating. People with TN may avoid normal activities due to concerns that a painful episode will occur.
How common is trigeminal neuralgia (TN)?
About 150,000 new cases of trigeminal neuralgia are diagnosed each year. It is more likely to occur in people over age 50, although people of any age may be affected. Typical trigeminal neuralgia is rare in people less than 40 years old. Multiple sclerosis should be considered in younger patients with TN. The incidence of trigeminal neuralgia in patients with MS is 1% to 2%.
What causes trigeminal neuralgia (TN)?
There are several conditions that may result in TN, but usually it is caused by pressure on the nerve exerted by a blood vessel near the brain stem. Multiple sclerosis (MS) causes the deterioration of the nerve coating called the myelin sheath, so people with MS may also develop TN.
Less commonly, a tumor or vascular lesion may cause nerve compression. Injury to the trigeminal nerve due to oral or sinus surgery, stroke, or facial trauma are other causes of facial nerve pain that may be similar to TN type pain.