The Epidemiology of Facial Pain

Assuming that the average age of the readership of this thesis is 35 years, and that 49% is male, given the number of theses printed (n=500) and the average life expectancy (78 years for men, 82.3 years for women), nine [95% confidence interval (95% CI): 8 - 10] readers (1.8%) will get a form of facial pain as studied in this thesis. Despite its low frequency the severity and debilitating nature of certain facial pain conditions is an important motivator for scientific research in this field. Facial pain comprises many different disease entities, which differ in aetiology, presentation, severity, frequency of occurrence and natural course of disease. In this thesis, we studied eight different forms of facial pain, including trigeminal neuralgia, postherpetic neuralgia in the facial area, cluster headache, occipital neuralgia with referred facial pain, local facial neuralgias, persistent idiopathic facial pain, glossopharyngeal neuralgia and paroxysmal hemicrania. These diseases share some clinical features and are often considered together in the differential diagnosis of a general practitioner. Facial pain conditions can be divided into primary (idiopathic) and secondary (symptomatic) facial pain based on the disease aetiology. While the aetiology of primary forms is largely unknown, secondary forms can be due to tumors, infarctions, arterio-venous malformations, multiple sclerosis and many other diseases.