Patient 1: A 73-year-old woman with history of migraine with aura developed persistent aura without infarction, manifesting as left gaze preference and right sided hemiplegia lasting 14 days. Brain MRI without gadolinium performed six days into the event showed cortical thickening/effaced sulci (T1 and T2), abnormal FLAIR signal, and diffusion restriction in the left parietal, occipital, and posterior temporal lobes with sparing of the subcortical white matter. Repeat MRI with gadolinium three days later showed no abnormal enhancement. These changes were absent on the initial scanning four days prior. Follow-up brain MRI performed 12 weeks later showed the left-sided focal abnormalities had completely resolved with no appearance of infarction.

Patient 2: A 57-year-old man with history of migraine with aura was hospitalised for a stroke-like event lasting 5-6 days, and ultimately diagnosed with probable migraine aura. Brain MRI with and without gadolinium performed on day 3 of the event showed gyriform T2 signal intensity involving the left posterior temporal, parietal, and occipital lobes without evidence of enhancement, restricted diffusion or susceptibility. There was relative hyperemia on perfusion imaging of the same regions. These findings had been absent on brain MRI performed two days earlier. A follow-up brain MRI performed five weeks later showed resolution of all previously seen abnormalities.

Our findings contribute insights into the reversible abnormalities observed on brain MRI during prolonged migraine aura, which underline the dynamic nature of the underlying processes of the migraine aura.