Migraine with Aura Phenomenology and Length

About 30 % of patients with migraine suffer from episodes of migraine with aura. Migraine with aura is characterized by transient focal neurologic symptoms, visual, sensory, or dysphasic, more rarely motor or brainstem, called ‘aura’ that are usually followed by a full migraine. The symptoms of the aura phase develop usually progressively over minutes and generally last for 5 to 60 minutes, although in a significant proportion of patients can be longer. The presumed substrate of migraine with aura is cortical spreading depression (CSD), a primarily neuronal phenomenon that causes a progressive shutdown of the cerebral cortex, starting from the occipital area and spreading onward at a speed of 2 to 3 mm per minute. The susceptibility to generate a CSD seems to be an intrinsic property of the migrainous brain.