Functional MRI as a biomarker for evaluation and prediction of effectiveness of migraine prophylaxis.

Migraine is a neurological disorder characterized by episodic head pain and visual cortical phenomena. The pathogenesis of migraine is unknown and remains to be determined. Bright light, flickering light and certain visual patterns can trigger a migraine attack, and visual cortical hyperexcitability has been hypothesized to be responsible. Interictally, the brain of migraineurs functions normally under general conditions but abnormally only under some specific conditions, such as the observation of stressful visual patterns, suggesting studying the brain function could provide insights in migraine pathophysiology. The functional MRI technique is unique in probing specific cortical area activation under various stimulation conditions and studying the abnormal cortical activation associated with functional disorders in migraine. In this perspective, we discuss how a novel functional MRI technique can be used to identify those migraineurs suffering visual cortical hyperexcitability, and its potential as a biomarker to evaluate and possibly predict effectiveness of migraine-preventive treatments.