Pearls & Oy-sters: Dynamics of altered cerebral perfusion and neurovascular coupling in migraine aura

A 37-year-old woman presented 90 minutes after acute onset of mild motor aphasia with word-finding difficulties and hypesthesia of the right arm.MRI was immediately performed as she presented within the 3-hour time window for IV thrombolysis.Diffusion-weighted images (DWI) were normal, but perfusion MRI (dynamic susceptibility contrast) sequences showed marked hypoperfusion in the left hemisphere affecting both middle cerebral artery and posterior cerebral artery (PCA) territories.These findings were considered compatible with migraine aura.The patient subsequently developed a mild left-sided headache.Clinical symptoms gradually improved to full recovery after 6 hours without specific treatment.Follow-up MRI perfusion scans were obtained 24 hours and 2 months after the episode.Functional transcranial Doppler (fTCD) from the P2segments of the PCA during visual stimulation was performed at the same time points as MRI (figure).The first follow-up MRI showed only mild residual hypoperfusion in the left hemisphere, and in the asymptomatic state 2 months later, no perfusion abnormality was detected.Correspondingly, initial severe changes of neurovascular coupling on fTCD were found with nearly no response to visual stimulation in the acute phase.After 24 hours, neurovascular coupling improved with a normal response on the asymptomatic right side and persisting changes in the left PCA, whereas at 2-month follow-up, a normal cerebrovascular response was observed.