Trigeminal Neuralgia (TN) is a common disorder that results in pain in the face or headache. While it can start out as a mild pain that comes and goes in very short attacks, as it progresses it can become very painful and result in longer, more frequent attacks lasting several minutes. Patients that have suffered with this disorder for longer periods of time can become incapacitated and unable to perform the activities of daily living as a result. Anesthesiologists are often involved in treating these patients either during the initial workup of headache, in pain clinics for chronic therapy or to give anesthesia for surgical intervention.

Trigeminal Neuralgia is also sometimes called tic douloreux because patients often grimace when they experience the pain associated with attacks. Attacks can be spontaneous or stimulated by relatively minor events such as brushing your teeth, combing your hair or applying makeup. Attacks can involve a small area or be spread widely along the distribution of the trigeminal nerve, the nerve that is affected by this disorder.

The trigeminal nerve is one of the largest nerves in the head. It is responsible for carrying sensation, pain, pressure and temperature signals from the face (near the jaw, gums, eyes and forehead areas). There is no clear reason for TN - although some cases have been shown to be due to compression of the nerve by a blood vessel, tumor, etc. and other cases have been related to demyelination (a loss of the insulating tissue around the nerve). Still, the actual cause of TN is not clearly understood and many times no structural cause can be identified.

Similarly, the pattern of the disease is not clearly understood. The right side of the face is five times more commonly affected than the left. It never occurs on both sides of the face. Women seem to be more commonly stricken than men (almost double the incidence). The disease usually affects people over age fifty - younger patients are quite rare. The disease is not associated with a shortened life span, but it is not self-limited, meaning that it does not go away on its own if left untreated.

The pain associated with TN is very definitive and easily localized by the patient. Sixty percent of patients complain of pain shooting from the corner of the mouth to the angle of the jaw. Thirty percent of patients have pain from the upper lip or teeth to the eye or eyebrow. In contrast to migraines, patients will rarely complain of attacks during sleep. Neurologic examination and laboratory tests are characteristically normal.

Treatment is initially approached with carbamazepine. In fact, the initial successful response to this drug is both distinctive and diagnostic. This initial relief is very satisfying for the patient, but with time most patients will experience breakthrough pain and require additional treatment options. Since most patients are older when they reach this stage, continued medical management seems to be the logical first step. A second or third medication is often needed at this point to control the pain. Common options include, but are not limited to, phenytoin, baclofen, oxcarbazepine, gabapentin, etc.

For patients that have failed medical therapy, there are some surgical options that should be considered. This situation can arise in as much as one fourth to one half of patients as the disorder progresses. Obviously surgery exposes the patient to the risks associated with having surgery and anesthesia and should not be undertaken lightly. There is the additional risk of permanent facial numbness or permanent facial pain (which can sometimes be worse than the original pain!). And of course, the surgery may not be successful in controlling the pain and medications may be needed even after surgery.

Two major surgical options exist currently: percutaneous procedures and microvascular decompression. In addition, gamma knife radiosurgery is under investigation as a newer, non-invasive and safer procedure.

Percutaneous procedures can usually be performed with local or general anesthesia on an outpatient basis. The simplest procedure involves an injection of alcohol to "kill" the nerve. This may result in good pain relief for a long period of time, but it is usually not permanent and the pain will return as the nerve regenerates. However, this is often the first step prior to moving on to a more involved percutaneous procedure.

Percutaneous Balloon Compression of the Trigeminal Nerve involves a balloon inserted near the area of the nerve which is then inflated for up to ten minutes. It has an 80-90% initial success rate, 25% recurrence of pain after the procedure and a very small chance of nerve damage/facial numbness.

Percutaneous Glycerol Rhizotomy involves a needle inserted into the area of the nerve followed by injection of glycerol to ablate the nerve. The patient has to remain seated for two hours after injection for full effect. This also has an 80-90% success rate with an occasional loss of facial sensation afterwards. However, recurrence rates are high - up to sixty percent

Percutaneous Radiofrequency Trigeminal Rhizotomy similarly involves a needle inserted near the nerve. In this procedure, a radiofrequency heating tip is used to ablate the nerve. Patients almost always have some residual facial numbness after this procedure, which has an 80-90% initial success rate. Recurrence rate may be as high as 25% with this procedure. However, this procedure has gained popularity because the patient can be awake during the procedure, they recover quickly and can go home the same day.

Microvascular Decompression is performed under general anesthesia and involves entering the skull behind the ear. Once the nerve is identified, it is padded with teflon felt. The initial response rate is about 95% with about a 30% recurrence rate. However, patients that receive this procedure can be pain free for much longer (up to 15 years or more) versus the percutaneous procedures (2-3 years average). Side effects of this more invasive surgery include hearing loss in about 4% of patients, significant facial weakness in about 2% of patients, and stroke in about 1% of patients. The risk of death does exist and is estimated to be about 0.5%. Recovery for this procedure is longer and requires about a week in the hospital.

One treatment that is currently still considered investigational is gamma knife radiosurgery. It is not widely available, limited to major medical centers that have the proper equipment. This procedure is non-invasive, painless and does not require anesthesia. There is a low risk of facial numbness (about 10%) with a 60-85% success rate. Since this procedure is fairly new, the long-term results are not know yet.

For more information about Trigeminal Neuralgia, contact the Trigeminal Neuralgia Association at: