Altered cerebrovascular response pattern in interictal migraine during visual stimulation

A dysbalance of the cerebrovascular response during functional activation o f the brain has been postulated as a factor in the pathophysiology of migra ine. To determine the dynamic pattern of the cerebrovascular response in mi graineurs compared with a control group, changes of the cerebral perfusion during cerebral activation were studied with high temporal resolution by fu nctional transcranial Doppler sonography (fTCD). The cerebral blood flow ve locity (CBFV) in the right posterior cerebral artery (PCA) and the left mid dle cerebral artery (MCA) was measured simultaneously during visual stimula tion in 19 interictal migraineurs and in 19 age- and sex-matched control su bjects. Data were analysed with a previously validated technique based on a utomated stimulus-related averaging of the CBFV. The MCA migraineurs exhibi ted a steady increase of CBFV during the stimulation, while normal subjects showed a habituation of the CBFV response. The lack of habituation in migr aineurs was significantly (P less than or equal to0.05) more pronounced acr oss patients with a high attack frequency (greater than or equal to4 per mo nth) compared with migraineurs with a low attack frequency (<4 per month). Ln the PCA, compared with normal subjects, migraineurs showed significantly (P<less than or equal to>0.05) stronger CBFV changes at the beginning and after the end of stimulation, with a slower decline to baseline. Data are i n accordance with electrophysiological findings in migraineurs. It is assum ed that a lack of habituation of the cerebrovascular response in migraineur s might contribute to a disturbance of the metabolic homeostasis of the bra in that might induce migraine attacks.