Neuroimaging in headache

The neurobiology of migraine is complex, but considerable progress has been made during recent decades with the aid of functional neuroimaging. Imaging studies have provided evidence of both abnormal brain functioning and structural changes. In migraine aura, the blood flow changes initially occur in V3A, an area also showing morphometric abnormalities. Pontine activation is also associated with increased volumetric changes. Similar findings are observed in the hypothalamic region in cluster headache. Other paroxysmal headache disorders, such as short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT), hemicrania paroxistica and hemicrania continua, share this similar pattern of activation as cluster headache, pointing to a common pathogenic mechanism. Further studies are required in order to determine whether these changes are the cause or the consequence of the disease, as well as the possible role they may play in the progression into a chronic disorder.