![]() In patients who experience auras very frequently and are bothered by them, preventive treatment with flunarizine or lamotrigine can be tried ( 10). To date, there is no reliably effective treatment. Migraine auras are usually self-limiting. Complex auras, e.g., successive visual and somatosensory auras, may last longer, but each individual modality should then last less than an hour. The blood oxygenation level-dependent (BOLD) signal migrated over the extrastriatal cortex at a rate of circa 3.5 mm/min, corresponding approximately to the speed calculated by Lashley in 1941 on the basis of observations of his own visual auras ( 9). Indirect confirmation of this concept was later provided by functional magnetic resonance imaging during spontaneous/triggered visual auras, showing changes in cerebral perfusion parallel to the diffusion of the visual aura in the field of vision ( 8). The neurophysiological correlate is cortical spreading depression (CSD), first described by Leão, in an animal experiment carried out in 1944, as a slow diffusion of stimuli over the cortex ( 7). Much rarer are visual auras in the form of altered object perception, with magnification or diminution (macropsia/micropsia) as in Alice in Wonderland syndrome (lifetime prevalence in patients with migraine: 15–19%) ( 5, 6). Although this form of visual aura is binocular, patients often do not realize it, frequently perceiving their vision as a 50/50 “screen” with the left half supplied by the left eye and the right half by the right eye. By the time the flickering has reached the periphery, it is usually no longer present centrally. Typical is the parallel or successive manifestation of irritative phenomena (“bright blinking lights”) and a visual field defect (“black hole”), as well as migration from central to peripheral. Characteristic of the typical visual aura is that it begins with development of a paracentral scotoma or of fortification figures (blinking diamond/kaleidoscope), followed by extension to the peripheral visual field. Overall, it is estimated that around 30% of migraine patients have auras, meaning that migraine auras can be assumed in about 3.5–8% of the population ( 1, 3, 4). “If I hold the affected eye closed, I see normally”
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