Background: Cerebrovascular dysregulation has long been associated with migraine pathophysiology, possibly mediated by hypoperfusion and/or endothelial dysfunction triggering cortical spreading depression. Vessel tortuosity has also been associated with altered hemodynamics and endothelial function. We sought to examine whether basilar artery (BA) tortuosity was altered in migraine.
Methods: We performed the Anatomy and Cerebral Hemodynamic Evaluation of Migraine (ACHE-M) study, a prospective, observational, case-control study including high-resolution MR angiography, arterial spin labeled perfusion MRI, and structural MRI. Migraine with aura (MWA), migraine without aura (MwoA), and control subjects between the age of 25-50 were enrolled in a 1:1:1 ratio. Subjects with manifest vascular disease of any type were excluded. Vertebral and basilar artery diameters and BA total lateral displacement from MRI were correlated with regional perfusion and T2/FLAIR white matter lesions that were assessed using methods similar to the Cerebral Abnormalities in Migraine Epidemiologic Risk Analysis study.
Results: 163 subjects were included (52 control/52 MWA/ 58 MwoA). Mean age was 33 ± 6 years, and 78% were female. BA diameter was similar across groups (3.6 ± 0.6 mm in all 3 groups). BA displacement was similar in MwoA (5.1±3.0 mm) and controls (4.9±3.1 mm), but tended to be greater in MWA (6.3±3.8 mm, p=0.055 vs. controls). In multivariate analysis incorporating migraine status, age, and sex, BA displacement was significantly associated with MWA (p=0.019), age (p<0.001), and sex (p=0.046). BA displacement was also significantly greater with increasing migraine frequency (p=0.003). There was no association with displacement and posterior cerebral artery territory cerebral blood flow or overall white matter lesion burden.
Conclusions: Basilar artery lateral displacement is associated with MWA as well as headache frequency, but this association does not appear to be mediated by cerebral hypoperfusion. Further investigation of the physiological consequences of basilar artery lateral displacement may lead to new insights into the mechanisms of migraine.