Transcranial Doppler evaluation in migraineurs.

Transcranial Doppler (TCD) enables indirect assessment of cerebral circulation by measurement of cerebral blood flow velocity. Stenosis and occlusion of cerebral vessels or cerebral vasospasm can be detected with this non-invasive method. Moreover, changes in cerebral blood flow velocity in response to hypercapnia or hypocapnia, exercise, temperature, orthostatic stress, visual and intellectual stimulation can be recorded and vasoreactivity or autoregulation mechanisms assessed. Migraine is considered to be a vasomotor disorder; its pathogenesis, however, is complex and requires further studies. TCD may help to detect mechanisms leading to migraine attack as well as during the attack and help to understand its pathophysiology. In this paper, the results of TCD examination in migraine patients in headache-free periods and during the attacks, in basal condition and during different stimulations, are presented. The influence of triptans on cerebral circulation is also described. Additionally, the role of TCD in diagnosis of patent foramen ovale in migraineurs is discussed.