Clinical and MRI characteristics of acute migrainous infarction

OBJECTIVE: Migrainous infarction is considered a rare complication of migraine. Although several studies reported silent brain lesions on neuroimaging in patients with migraine with aura, knowledge about lesion patterns in acute migrainous infarction is scarce. We investigated clinical and MRI characteristics in a series of patients with migraine-associated acute cerebral ischemia. METHODS: Seventeen patients among 8,137 stroke patients over an 11-year period were included. All had undergone a dedicated stroke workup including diffusion-weighted imaging (DWI) and a detailed assessment of clinical features and of vascular risk factors. RESULTS: The majority of patients presented with prolonged aura symptoms (visual aura 82.3%, sensory dysfunction 41.2%, and aphasia 5.9%; median NIH Stroke Scale score 2). Presentation at hospital was significantly delayed after symptom onset (mean 33 hours). A total of 70.6% had acute ischemic lesions in the posterior circulation; the middle cerebral artery territory was affected in 29.4%. Small lesions were present in 64.7%; multiple lesions were found in 41.2%. No overlapping ischemic lesions of different vascular territories were found. The prevalence of a patent foramen ovale was high (64.7%). CONCLUSIONS: This study supports previous observations that migrainous infarction mostly occurs in the posterior circulation, and in younger women with a history of migraine with aura. Acute ischemic lesions were often multiple and located in distinct arterial territories. As there were no overlapping ischemic lesions, hemodynamic compromise during the development of migraine is unlikely the cause of infarction. Differentiation between migrainous infarction and prolonged migraine aura is difficult and associated with delayed admission of patients.