The various forms of recurrent facial pain can sometimes be debilitating, but are fortunately relatively uncommon, according to a new study.

There are a number of painful syndromes affecting the face and head that can arise on their own or result from an underlying cause such as a tumor, multiple sclerosis or stroke. It has not been clear, however, exactly how common these problems are in the general population.

In the new study, researchers used a database with the electronic medical records of about 800,000 patients in the Netherlands to estimate the rates of eight different facial pain syndromes.

Overall, the study found, the conditions were seen at a rate of 38 cases per 100,000 people each year. That is somewhat higher than earlier, hospital-based studies had suggested -- but still indicates that facial pain is relatively rare, the researchers report in the journal Pain.

The two most common disorders were trigeminal neuralgia and cluster headache, which each accounted for about one-third of all cases of facial pain.

Trigeminal neuralgia occurs in the trigeminal nerve, which affects perceptions of touch, pain and temperature in the face and jaw. The condition is marked by shock-like or stabbing facial pain that may be triggered by everyday actions such as talking, chewing and brushing one's teeth.

Cluster headaches cause sudden, severe pain, often centered in one eye. Though the headaches tend to be short, they run in cycles, which may cause several headaches in one day or every few days. Both cluster headaches and trigeminal neuralgia can be debilitating and difficult to treat.

The two least common facial pain types were glossopharyngeal neuralgia (diagnosed in two people) and paroxysmal hemicrania, which was diagnosed in one person. The former affects the glossopharyngeal nerve deep in the neck and causes severe, stabbing pain in the throat, tongue and middle ear.

Paroxysmal hemicrania is a form of headache that causes multiple attacks of pain per day -- usually on one side of the face and sometimes accompanied by red, teary eyes or a swollen or drooping eyelid on the affected side of the head.

Although the symptoms of some of these forms (of facial pain) can be severe, they are, luckily enough, rare, lead researcher Dr. Joseph S.H.A. Koopman, of Erasmus University Medical Center in Rotterdam, told Reuters Health in an email.

Diagnosing the different forms of facial pain can be difficult. By putting figures on the rates of these disorders, the current findings may be helpful to doctors when they are trying to narrow down the possible diagnoses for a patient's symptoms, according to Koopman.

The incidence of a disease, he said, determines the a priori chance, or likelihood, that it accounts for a person's symptoms.

SOURCE: Pain, December 15, 2009.

Medicine