A population of 45 young subjects, 16 males and 29 females, affected by migraine with aura were studied prospectively. The mean follow-up was 7 years 6 months. The clinical characteristics and modifications during migraine aura attacks were evaluated. The aura propagated slowly with a pattern corresponding to a cortical pathway in the posteroanterior direction in 71% of the series, and was visual alone in 40%. Analysis of the relation between the course, and therefore prognosis, and the aura type showed that headache has a better prognosis when symptoms continue to be only visual. The International Headache Society (IHS) classification subdivides migraine with aura into six categories based on the duration of symptoms and the clinical characteristics (hemiplegic, basilar). Our results suggest that subjects with only visual aura should be considered separately, possibly as a seventh category, because they may have a more favourable prognosis.