Atypical Facial Pain/Persistent Idiopathic Facial Pain

Abstract

Atypical facial pain (AFP) or persistent idiopathic facial pain (PIFP) is a chronic pain syndrome characterized by persistent facial and/or oral pain not clearly attributable to other facial or dental pathology. The precise incidence and prevalence of PIFP are unknown; however, it is believed to be a rare disease even among the idiopathic chronic pain syndromes. The pathophysiology of PIFP is poorly understood, but the syndrome is generally thought to result from a combination of biological and psychological factors. Alterations in dopaminergic signaling and brainstem excitation have been noted in patients with PIFP; in addition, patients with PIFP often have psychiatric comorbidities. Agents commonly used in the treatment of PIFP include amitriptyline and the other tricyclic antidepressants (TCAs), venlafaxine, and fluoxetine; however, there is limited data to support a single treatment pathway. Non-pharmacologic treatment modalities include cognitive-behavioral therapy (CBT) as well as non-evidence practices such as acupuncture and hypnosis. Interventional pain strategies include sphenopalatine ganglion block and pulsed radiofrequency treatment. Current research aims to better elucidate the pathophysiology of the condition using sophisticated imaging modalities, as well as to define the role for other pharmacological and interventional treatment strategies.