At some point in life, most people will experience facial pain. This includes sinus infections, eye irritation, ear aches and tooth aches. Then there are chronic pain syndromes, which afflict certain people over the course of their lives. About four out of every 100,000 people in the US will develop chronic facial pain each year. The most common is Trigeminal Neuralgia (TN).
This condition is characterized by sudden episodes of sharp pain, called paroxysms. They typically last a few seconds, but are excruciating. Symptoms can be triggered by the simplest thing, such as touching one’s face, brushing one’s teeth or chewing. The pain can be traced to the main sensory nerve to the face, called the Trigeminal nerve. It has three primary branches. The first is the Ophthalmic division because it serves the area around the eye and upper part of the face. The second is the Maxillary division and supplies the area of the cheekbone. And the third is the Mandibular division, serving the area of the lower jaw.
TN is more common in people who have Multiple Sclerosis, affecting two percent of patients who have that condition. Also 20 percent of those who experience TN on both sides of the face, which is rare, also have MS. TN affects the right side of the face twice as often as the left, is twice as common in women than in men, and more often causes pain in the cheekbone and jaw area.
The most common cause of TN is compression of the nerve by a small blood vessel, where it enters the back of the brain. Tumors can also cause TN, as can Multiple Sclerosis. Several conditions should be ruled out before TN is diagnosed, including shingles, Temporal Arteritis (a tender, swollen artery beneath the skin just in front of the ear), and other diseases of the eye or teeth.
Treatment of TN may involve medication, surgery or both. The medication that is generally used is Tegretol (carbamazepine), a seizure medication that works because what is occurring in the nerve is much like a seizure in the brain. While many patients require fairly high daily doses of the medication to get symptoms under control, the drug is relatively inexpensive and side effects are tolerable. However, regular follow up with a doctor is important. Other medications that have proven effective for some patients include Lioresal (baclofen) and Neurontin (gabapentin).
Patients who cannot get control of their symptoms often seek relief through neurosurgery. The kind of surgical treatment will depend upon what is causing the symptoms. If it is a tumor, it is usually removed. Another approach is to separate the small artery in the back of the brain from the nerve, a procedure called a Microvascular Decompression or MVD. This is often the best treatment. However, if a patient is too old or ill to have it, has MS (which makes them ineligible for this surgery), or the procedure fails after two or three attempts, there are other options that are less invasive.
Unfortunately, they tend to be only temporarily effective and must be repeated after a year or two. These involve placing a needle in the face just under the cheekbone and inserting it into the hole in the underside of the skull, where the Trigeminal nerve exits before it enters the face. Once the needle is properly located with the aid of X-rays, any number of manipulations are used to effectively “deaden” or damage the nerve. This causes numbness on the face, which can be most welcome to those who are plagued by excruciating pain.
Manipulations may include:
—inserting a small tube (catheter) with a tiny balloon on the end that can be inflated causing high pressure on the nerve
—inserting a small electrode that transmits a radio frequency current that damages the nerve
—injecting a small amount of a certain alcohol, which also damages the nerve
—a precisely focused beam of high-energy radiation called Radiosurgery
If you are affected by TN, learn as much about it as you can, and then seek expert advice from a neurologist or a neurosurgeon. Remember to get two opinions to help you make the most informed decision about your health.
by Thomas Chappell MD