When a Nerve Is a Live Wire
Gary E Cordingley, MD, PhD
When painful jabs invade one side of your face, you might feel you have lost control.
But help is available.
Of all the places in the body that can hurt, the face might seem the strangest. But for some people, that's
exactly where the agony occurs, and the cause is a nerve gone haywire.
How peripheral nerves involve themselves in pain is sometimes confusing. Here's a handy way to think of the
two basic patterns:
#1: The nerve is the messenger. If you have a dental abscess, a facial sunburn or a sinus infection, you can
count on pain being present. Where does it come from? Special nerve endings detect the tissue-injury and
generate electrical impulses. The peripheral nerves carry these impulses into the brain. The peripheral
nerves didn't CAUSE the pain, they're just carrying the bad news. (Don't shoot the messenger!)
#2: The nerve itself is the mischief-maker. In some cases the nerve generates abnormal impulses on its own.
The nerve is still capable of carrying normal impulses, like those informing the brain that the skin of the face is
warm or cold—or that you cut yourself shaving—but generates signals of its own as well that the brain can only
interpret as painful.
When peripheral nerves generate bolts of pain in the forehead, eye, cheek or jaw, it's called trigeminal
neuralgia. This technical term can be broken into its parts, starting at the end and working forward. "Algia"
means pain. A "neur-algia" means nerve-pain. Finally, "trigeminal" is the name of the nerve involved. So
"trigeminal neuralgia" means pain caused by the trigeminal nerve. We have two trigeminal nerves, one for
each side of the face. They are among the largest nerves in our heads.
An older term for trigeminal neuralgia was "tic douloureux." This bears explaining. A "tic" is a sudden, brief
movement. "Douloureux" is the French word for "painful." So a "tic douloureux" means that a sudden, brief
movement and a pain occur together. However, this terminology was largely abandoned because it implies
that movement is an essential feature. It isn't. When movement is present, it's just as a reaction to the pain.
So what are the usual features of trigeminal neuralgia? First of all, it almost always occurs on just one side of
the face. If one of our trigeminal nerves gets involved in this unfortunate condition, it's rare indeed that the
second trigeminal nerve would be so unlucky to get involved, too. Or another way of looking at it is this: if the
pain switches sides or crosses the midline, then it's probably not trigeminal neuralgia.
Trigeminal neuralgia usually involves brief, but intense jabs of pain, though is sometimes more steady and
continuous. It can also get revved-up by external stimuli, like washing the face, putting on make-up, brushing
teeth, chewing—and sometimes just talking.
The most usual form of trigeminal neuralgia begins after the age of 50. And, once present, it tends to hang
around. Its course—like that of the stock market—fluctuates.
Treatment is not usually curative, but help is still available. Most patients obtain relief through one or a
combination of medications that either simmer down the extra nerve-impulses or reduce the effects of the
barrage of extra signals that arrive in the brain. Some of their generic names are carbamazepine, gabapentin,
baclofen, clonazepam and lamotrigine.
A minority of patients with this condition undertake surgery for it. One surgery involves purposely damaging
the trigeminal nerve-fibers where they gather together in a structure called a ganglion. This approach is fairly
safe, but produces partial numbness on the face.
Another surgery goes straight to where the trigeminal nerve fibers meet the brain. The surgeon gently
separates the nerve from its surrounding tissues. The good part of this procedure is that it doesn't seek to
damage tissue. The downside is that the location for the surgery is at an important cross-roads for many
nerve and brain pathways, so a complication can be devastating. While some people get long-lasting relief
from the surgeries, others obtain just temporary respite.
While the foregoing summary of treatments sounds gloomy, it's important to realize that most people who seek
medical treatment for their trigeminal neuralgia are able to arrive at a happy point where pain is minimized and
quality of life is maximized. The neuralgia no longer rules their lives; instead, they're in control of the neuralgia.
(C) 2005 by Gary Cordingley